NosoVeille n°11 Novembre 2009 Rédacteurs : Nathalie Sanlaville

NosoVeille n°11
Novembre 2009
Rédacteurs : Nathalie Sanlaville, Sandrine Yvars, Annie Treyve
Ce bulletin de veille est une publication mensuelle qui recueille les publications
scientifiques publiées au cours du mois écoulé.
La recherche documentaire est effectuée dans la base de données
Pour recevoir, tous les mois, NosoVeille dans votre messagerie :
Abonnement / Désabonnement
Sommaire de ce numéro
Acinetobacter
Antibiotique
Bactériémie
Chirurgie
Environnement
Grippe
Hémodialyse
Hépatite C
Hygiène des mains
Pédiatrie
Personnel
Pneumonie
Réanimation
Staphylococcus aureus
Surveillance
Acinetobacter
NosoBase n° 25717
Epidémie d'infections à Acinetobacter baumannii multirésistant aux antibiotiques dans une unité de
réanimation polyvalente : analyse clinique, épidémiologique et évolution du profil PFGE
Monterrubio-Villar J; Gonzalez-Velasco C; Valdezate-Ramos S; Cordoba-Lopez A; Villalon-Panzano P;
Saez-Nieto JA. Outbreak of multiresistant Acinetobacter baumannii in a polyvalent intensive care unit:
clinical, epidemiological analysis and PFGE-printing evolution. European journal of clinical microbiology and
infectious diseases 2009/10; 28(10): 1281-1284.
Mots-clés : EPIDEMIE; ACINETOBACTER BAUMANNII; ANTIBIOTIQUE; MULTIRESISTANCE; SOIN
INTENSIF; EPIDEMIOLOGIE; ANALYSE; PFGE; MORTALITE; CONTROLE; TYPAGE
An outbreak of multidrug-resistant Acinetobacter baumannii (MRAB) occurred over the course of a 27-week
period in our adult polyvalent intensive care unit (ICU). Twenty-one patients were affected, and 72 strains
were identified from different clinical samples. The strains were resistant to all antibiotics except for colistin
and ampicillin/sulbactam. Forty-nine MRAB strains collected from 18 patients were analysed by pulsed-field
gel electrophoresis (PFGE). This analysis revealed four highly-related PFGE types (genetic similarity index
>90%) termed 1, 2, 3 and 4, that were isolated in 13, seven, one, and three patients, respectively. A single
PFGE type was identified from five of ten patients with successive isolation of MRAB; in the other five
patients, two or three PFGE types were detected. This suggested phased evolution of PFGE types 2, 3 and
4 from PFGE type 1. Global mortality was high (13 patients; 62%). Non-survivors had higher APACHE II
scores than survivors on the date that MRAB was isolated (OR = 1.57; 95% CI [1.02, 2.44]). The outbreak
was controlled after implementation of an extensive infection control program.
NosoBase n° 25681
Les souches cliniques d'Acinetobacter baumannii tolérantes aux biocides et multirésitantes aux
antibiotiques sont associées à une formation élevée de biofilm
Rajamohan G; Srinivasan VB; Gebreyes WA. Biocide-tolerant multidrug-resistant Acinetobacter baumannii
clinical strains are associated with higher biofilm formation. The Journal of hospital infection 2009/11; 73(3):
287-289.
Mots-clés : BIOFILM; BIOCIDE; ACINETOBACTER; MULTIRESISTANCE
Antibiotique
NosoBase n° 25562
Prescription des antibiotiques en urologie reposant sur des preuves : synthèse de cinq ans de
résultats microbiologiques
Dasgupta R; Sullivan R; French G; O'Brien T. Evidence-based prescription of antibiotics in urology: a 5-year
review of microbiology. BJU international 2009/09; 104(6): 760-764.
Mots-clés : ANTIBIOTIQUE; MICROBIOLOGIE; PRESCRIPTION; UROLOGIE; URINE; PREVALENCE;
ANTIBIORESISTANCE; STREPTOCOCCUS; ESCHERICHIA COLI
Objective: To analyse the results of positive urine cultures over a 5-year period in a large hospital and
urology department (amongst both inpatients and outpatients), assess the prevalence of different organisms
and the resistance profiles of a range of antibiotics, and thus provide information on which organisms are
likely to cause urosepsis.
Methods: The use of antibiotics should be based on knowledge of which pathogens are present and what
resistance patterns are emerging, particularly relevant in surgical disciplines like urology, as antibiotics are
now routinely administered peri-operatively, whereby evidence-based prescription is preferable to generic
guidelines. We therefore examined almost 25,000 positive urine cultures in our hospital over a 5-year period,
and focused on the infections encountered amongst urology patients during this time.
Results: A significant proportion of inpatient urinary infection (40%) is caused by Gram-positive bacteria
such as Streptococcus faecalis, underlining the need for including Gram-positive cover during urological
prophylaxis. The commonest pathogen remains Escherichia coli among both inpatients and outpatients. The
ineffectiveness of common antibiotics such as ciprofloxacin and trimethoprim was identified, as was the
increase in gentamicin resistance.
Conclusion: We propose using an aminoglycoside with a penicillin for high-risk cases (e.g. endoscopic stone
surgery) while low-risk cases (e.g. flexible cystoscopy with no risk factors) might be managed without such
prophylaxis. Pathogenic patterns and resistance rates should be monitored regularly.
NosoBase n° 25596
Pseudomonas aeruginosa. Un phénomène de résistance bactérienne
Strateva T; Yordanov D. Pseudomonas aeruginosa - a phenomenon of bacterial resistance. Journal of
medical microbiology. 2009/09; 58(9): 1133-1148.
Mots-clés
:
FLUOROQUINOLONE;
PSEUDOMONAS
AERUGINOSA;
ANTIBIORESISTANCE;
BETALACTAMINE; AMINOSIDE
Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide. Nosocomial infections
caused by this organism are often hard to treat because of both the intrinsic resistance of the species (it has
constitutive expression of AmpC beta-lactamase and efflux pumps, combined with a low permeability of the
outer membrane), and its remarkable ability to acquire further resistance mechanisms to multiple groups of
antimicrobial agents, including beta-lactams, aminoglycosides and fluoroquinolones. P. aeruginosa
represents a phenomenon of bacterial resistance, since practically all known mechanisms of antimicrobial
resistance can be seen in it: derepression of chromosomal AmpC cephalosporinase; production of plasmid
or integron-mediated beta-lactamases from different molecular classes (carbenicillinases and extendedspectrum beta-lactamases belonging to class A, class D oxacillinases and class B carbapenem-hydrolysing
enzymes); diminished outer membrane permeability (loss of OprD proteins); overexpression of active efflux
systems
with
wide
substrate
profiles;
synthesis
of
aminoglycoside-modifying
enzymes
(phosphoryltransferases, acetyltransferases and adenylyltransferases); and structural alterations of
topoisomerases II and IV determining quinolone resistance. Worryingly, these mechanisms are often
present simultaneously, thereby conferring multiresistant phenotypes. This review describes the known
resistance mechanisms in P. aeruginosa to the most frequently administrated antipseudomonal antibiotics:
beta-lactams, aminoglycosides and fluoroquinolones.
NosoBase n° 25723
Usage des antibiotiques et risques de colonisation et d'infection par des bactéries résistant aux
antibiotiques. Etude d'une population hospitalière
Tacconelli E; De Angelis G; Cataldo MA; Mantengoli E; Spanu T; Pan A et al. Antibiotic usage and risk of
colonization and infection with antibiotic-resistant bacteria: a hospital population-based study. Antimicrobial
agents and chemotherapy 2009/10; 53(10): 4264-4269.
Mots-clés : ANTIBIOTIQUE; ANTIBIORESISTANCE; COLONISATION; RISQUE; FACTEUR DE RISQUE;
COHORTE; PFGE; STAPHYLOCOCCUS AUREUS; METICILLINO-RESISTANCE; ENTEROCOCCUS;
VANCOMYCINE; PSEUDOMONAS AERUGINOSA; CARBAPENEME; CENTRE HOSPITALIER
UNIVERSITAIRE
Accurate assessment of risk factors for nosocomial acquisition of colonization by antibiotic-resistant bacteria
(ARB) is often confounded by scarce data on antibiotic use. A 12-month, nested, multicenter cohort study
was conducted. Target ARB were methicillin (meticillin)-resistant Staphylococcus aureus (MRSA),
vancomycin-resistant enterococci (VRE), and ciprofloxacin-resistant Pseudomonas aeruginosa (CR-PA).
Nares and rectal swabs were obtained before and after starting antibiotics. Pulsed-field gel electrophoresis
was done to define genetic relatedness of the strains. Primary outcomes were (i) the mean time, in days, for
acquisition of target ARB colonization in patients previously not colonized; (ii) the rate of acquisition per
1,000 antibiotic-days according to different classes of antibiotics; (iii) the rate of infection caused by the
same bacteria as those previously isolated in screening samples; and (iv) the risk factors for ARB
acquisition. In total, 6,245 swabs from 864 inpatients were processed. The rate of acquisition was 3%, 2%,
and 1% for MRSA, VRE, and CR-PA, respectively. The rate of acquisition of ARB per 1,000 antibiotic-days
was 14 for carbapenems, 9 for glycopeptides, and 6 for broad-spectrum cephalosporins and quinolones.
The highest rates of acquisition were observed for carbapenems in dialyzed and diabetic patients. Four risk
factors were independently associated with acquisition of target ARB: use of carbapenems, age of >70
years, hospitalization for >16 days, and human immunodeficiency virus infection. During the 30-day follow-
up, 4 among 42 patients newly colonized by ARB (9%) suffered from an infection due to the same bacteria
as those isolated in a previous screening sample. Colonizing and infecting strains from single patients were
genotypically identical. Identifying ARB colonization early during antibiotic therapy could target a high-risk
hospitalized population that may benefit from intervention to decrease the risk of subsequent nosocomial
infections
NosoBase n° 25571
Détection de bêta-lactamases à spectre élargi dans des bacilles à Gram négatif d'origine
nosocomiale
Tsering DC; Das S; Adhiakari L; Pal R; Singh T. Extended spectrum beta-lactamase detection in gramnegative bacilli of nosocomial origin. Journal of global infectious diseases 2009/12; 1(2): 87-92.
Mots-clés : BETA-LACTAMASE A SPECTRE ELARGI; DEPISTAGE; BACILLE GRAM NEGATIF;
ANTIBIORESISTANCE; CEPHALOSPORINE TROISIEME GENERATION; ESCHERICHIA COLI;
PSEUDOMONAS; KLEBSIELLA PNEUMONIAE; MULTIRESISTANCE; PREVALENCE
Background: resistance to third generation cephalosporins by acquisition and expression of extended
spectrum beta lactamase (ESBL) enzymes among gram-negative bacilli is on a rise. The presence of ESBL
producing organisms significantly affects the course and outcome of an infection and poses a challenge to
infection management worldwide.
Materials and Methods: in the period from June 2007 to 2008, we collected 1489 samples from patients
suspected of nosocomial infection. The isolates were identified based on colony morphology and
biochemical reaction. Gram negative bacilli resistant to third generation cephalosporins were tested for
ESBL by double disc synergy test (DDST- a screening test) and then phenotypic confirmatory test.
Antimicrobial susceptibility testing was done by modified Kirby Bauer disc diffusion method.
Results: from the sample of 238 gram-negative bacilli, we isolated Escherichia coli, Pseudomonas
aeruginosa, Klebsiella pneumoniae, Citrobacter freundii, Proteus mirabilis, Morganella morganii and
Enterobacter cloacae. Following both methods, 34% isolates were ESBL-positive. The ESBL producing
isolates were significantly resistant (p < 0.01) to ampicillin, piperacillin, piperacillin/tazobactam,
trimethoprim/sulfamethoxazle, tetracycline, ciprofloxacin and gentamicin as compared to non-ESBL
producers. Multidrug resistance was significantly (p < 0.01) higher (69.14%) in ESBL positive isolates than
non-ESBL isolates (21.66%).
Conclusion: high prevalence of ESBL in our hospital cannot be ignored. ESBL producers can be detected by
DDST and phenotypic confirmatory test with equal efficacy. The sensitivity of screening test improved with
the use of more than one antibiotic and addition of one or two antibiotics would not increase cost and labor.
We recommend DDST using multiple antibiotics in all microbiology units as a routine screening test.
NosoBase n° 25657
Corrélation entre l'usage des antibiotiques et l'antibiorésistance dans un hôpital : observations dans
le temps et spécifiques par service
Willemsen I; Bogaers-Hofman D; Winters M; Kluytmans J. Correlation between antibiotic use and resistance
in a hospital: temporary and ward-specific observations. Infection 2009/10; 37(5): 432-437.
Mots-clés
:
ANTIBIOTIQUE;
ANTIBIORESISTANCE;
PREVALENCE;
CIPROFLOXACINE;
BETALACTAMINE
Objectives: The objectives of this study were to determine (1) the increase in antimicrobial resistance to
frequently used antibiotics in the hospital setting over time and (2) the correlation between the amount of
use of an antibiotic in a specific medical specialty and the observed resistance to that antibiotic in that
specialty.
Method: The total use of antibiotics and the use of ciprofloxacin (CIP), co-amoxicillin + clavulanic acid
(AMCL) and first- and second-generation cephalosporins (CEF), respectively, in individual medical
specialties were measured between 2001 and 2006 by means of prevalence surveys (two per year). The
antimicrobial susceptibility patterns among E. coli isolated from hospitalized patients between 2003 and
2006 were obtained from the Laboratory Information System. Trends over time and correlation between use
and resistance were calculated.
Results: 6,639 patients were included in the prevalence surveys, of whom 3.0% (195) were treated with CIP,
9.7% (642) with AMCL, and 3.5% (232) with CEF. 4,790 E. coli isolates were obtained from hospitalized
patients. Resistance to all antibiotics significantly increased over time, with the regression line showing that
the strongest increase in resistance was for CIP (2.6% per year). There were large variations in antimicrobial
use between various medical specialties. A significant correlation was found between the ward-specific
prevalence of use and the percentage of resistance for CIP (R = 0.81, p < 0.001) and AMCL (R = 0.82, p =
0.003).
Conclusion: At the level of individual medical specialties within one hospital, a higher prevalence of
antimicrobial use among patients was associated with a significantly higher observed antimicrobial
resistance. The use of CIP was associated with a stronger increase in resistance than the use of betalactams.
Bactériémie
NosoBase n° 25689
Variations saisonnières des bactériémies à Escherichia coli : étude de population
Al-Hasan MN; Lahr BD; Eckel-Passow JE; Baddour LM. Seasonal variation in Escherichia coli bloodstream
infection: a population-based study. Clinical microbiology and infection 2009/10; 15(10): 947-950.
Mots-clés :
ESCHERICHIA
COLI;
BACTERIEMIE;
TAUX;
INFECTION
COMMUNAUTAIRE;
EPIDEMIOLOGIE; INCIDENCE
Seasonal variation in the rates of infection with certain Gram-negative organisms has been previously
examined in tertiary-care centres. We performed a population-based investigation to evaluate the seasonal
variation in Escherichia coli bloodstream infection (BSI). We identified 461 unique patients in Olmsted
County, Minnesota, from 1 January 1998 to 31 December 2007, with E. coli BSI. Incidence rates (IR) and IR
ratios were calculated using Rochester Epidemiology Project tools. Multivariable Poisson regression was
used to examine the association between the IR of E. coli BSI and average temperature. The age- and
gender-adjusted IR of E. coli BSI per 100 000 person-years was 50.2 (95% CI 42.9-57.5) during the
warmest 4 months (June through September) compared with 37.1 (95% CI 32.7-41.5) during the remainder
of the year, resulting in a 35% (95% CI 12-66%) increase in IR during the warmest 4 months. The average
temperature was predictive of increasing IR of E. coli BSI (p 0.004); there was a 7% (95% CI 2-12%)
increase in the IR for each 10-degree Fahrenheit (c. 5.5 degrees C) increase in average temperature. To our
knowledge, this is the first study to demonstrate seasonal variation in E. coli BSI, with a higher IR during the
warmest 4 months than during the remainder of the year.
NosoBase n° 25668
Corrélation des incidences des bactériémies nosocomiales : étude écologique
Benet T; Vanhems P. Correlation of nosocomial bloodstream infection incidences: an ecological study.
The Journal of hospital infection 2009/11; 73(3): 217-224.
Mots-clés : INCIDENCE; BACTERIEMIE; EPIDEMIOLOGIE; PREVENTION; ETUDE PROSPECTIVE; SOIN
INTENSIF; HEMATOLOGIE; CENTRE HOSPITALIER UNIVERSITAIRE; HEMOCULTURE; TAUX
This study aimed to correlate nosocomial bloodstream infections (NBIs) across time against the ecological
effect of infection control activities. All patients hospitalised >/=48h in the haematology and intensive care
departments of a university hospital and discharged between 1 January 2004 and 30 June 2006 were
prospectively included. The case definition of NBI infection was: (1) at least one positive blood culture
justified by clinical signs, or (2) at least two positive blood cultures when the micro-organism was one of the
following: coagulase-negative staphylococci, Bacillus spp. (except Bacillus anthracis), Corynebacterium
spp., Propionibacterium spp., Micrococcus spp., or other commensal with similar pathogenicity, if occurring
>/=48h after patient admission. NBI incidences were correlated in quarterly intervals using Spearman's test
and linear regression. In total, 3829 patients accounting for 46 474 patient-days at risk were included. We
identified 101 NBIs in intensive care and 286 NBIs in haematology. There was a correlation between NBI
incidence in haematology with the NBI incidence in intensive care (r=0.68, P=0.042). The linear model for
NBI incidences between departments was R(2)=0.52, with a positive trend (P=0.029). A common
determinant such as improved hygiene measures is the most likely reason for this association.
NosoBase n° 25424
Taux de mortalité attribuable aux bactériémies à Klebsiella pneumoniae résistant aux carbapénèmes
Borer A; Saidel-Odes L; Riesenberg K; Eskira S; Peled N; Nativ R; et al. Attributable mortality rate for
carbapenem-resistant Klebsiella pneumoniae bacteremia. Infection control and hospital epidemiology
2009/10; 30(10): 972-976.
Mots-clés : MORTALITE; BACTERIEMIE; KLEBSIELLA PNEUMONIAE; CARBAPENEME; ETUDE
RETROSPECTIVE
Objective: To determine the attributable (direct) mortality and morbidity caused by carbapenem-resistant
Klebsiella pneumoniae bacteremia.
Design: A matched retrospective, historical cohort design, using a stepwise procedure to stringently match
the best control subjects to the best case subjects.
Setting: A 1,000-bed tertiary-care university teaching hospital.
Patients: Case subjects were defined as adult patients with carbapenem-resistant K. pneumoniae
bacteremia during the period from October 2005 through October 2008. Control subjects were defined as
patients who were very similar to case subjects except that they did not have bacteremia.
Methods: Matching potential control subjects to case subjects was performed at a 1:1 ratio using a
computerized record system. The criteria used included same hospitalization period, similar Charlson
comorbidity index, same underlying disease, same age within 10 years, and same sex. Demographic and
clinical characteristics were collected from medical records.
Results: During the study period, 319 patients developed an infection due to carbapenem-resistant K.
pneumoniae. Of these 319 patients, 39 (12.2%) developed a bloodstream infection, for an overall rate of
0.59 episodes of carbapenem-resistant K. pneumoniae bacteremia per 10,000 patient-days. We excluded 7
patients from our study, leaving a total of 32 case subjects in our cohort. Case subjects were significantly
more likely than control subjects (n = 32) to require care in an intensive care unit (12 case subjects [37.5%]
vs 3 control subjects [9.4%]), ventilator support (17 case subjects [53.1%] vs 8 control subjects [25%]), and
use of a central venous catheter (19 case subjects [59.4%] vs 9 control subjects [28.1%]). For case subjects,
the crude mortality rate was 71.9% (ie, 23 of the 32 case subjects died); for control subjects, the crude
mortality rate was 21.9% (ie, 7 of the 32 control subjects died) (P < .001. For case subjects, the attributable
mortality was 50% (95% confidence interval [CI], 15.3%-98.6%). A mortality risk ratio of 3.3 (95% CI, 2.928.5) was found for case subjects with carbapenem-resistant K. pneumoniae bacteremia.
Conclusions: Patients with carbapenem-resistant K. pneumoniae require more intensive and invasive care.
We have shown that the crude and attributable mortality rates associated with carbapenem-resistant K.
pneumoniae bacteremia were striking.
NosoBase n° 25688
Bactériémies dans une unité de réanimation médico-chirurgicale : incidence, étiologie, profils
d'antibiorésistance de bactéries à Gram négatif et à Gram positif
Erdem I; Ozgultekin A; Sengoz Inan A; Ozturk Engin D; Akcay SS; Turan G et al. Bloodstream infections in
a medical-surgical intensive care unit: incidence, aetiology, antimicrobial resistance patterns of grampositive and gram-negative bacteria. Clinical microbiology and infection 2009/10; 15(10): 943-946.
Mots-clés : BACTERIEMIE; SOIN INTENSIF; INCIDENCE; ANTIBIORESISTANCE; BACTERIE A GRAM
POSITIF; BACTERIE A GRAM NEGATIF;
STAPHYLOCOCCUS AUREUS; ANTIBIOTIQUE
In the present study, the incidence and antimicrobial resistance patterns of the microorganisms that caused
bloodstream infections (BSIs) in a medical-surgical intensive care unit during the years 2005-2007 were
determined. The mean BSI incidence density was 6.56 per 1000 patient-days. The incidence density
increased linearly during the study period (from 3.57 to 9.60 per 1000 patient-days). Staphylococcus aureus
was most frequently isolated (47.3%), followed by Enterococcus spp. (10.8%) and Candida spp. (10.1%).
There was a high rate of resistance to several of the prescribed antimicrobials among the bacteria isolated
from patients with BSIs.
NosoBase n° 25543
Incidence, facteurs de risque et évolution des bactériémies à Klebsiella pneumonia
Meatherall BL; Gregson D; Ross T; Pitout JD; Laupland KB. Incidence, risk factors, and outcomes of
Klebsiella pneumoniae bacteremia. The American journal of medicine 2009/09; 122(9): 866-873.
Mots-clés : INCIDENCE; FACTEUR DE RISQUE; KLEBSIELLA PNEUMONIAE; BACTERIEMIE;
EPIDEMIOLOGIE;
SURVEILLANCE;
INFECTION
COMMUNAUTAIRE;
DIALYSE
RENALE;
TRANSPLANTATION; CANCER; MORTALITE; ANTIBIORESISTANCE
Background: Although Klebsiella pneumoniae is the second most common cause of Gram-negative
bloodstream infections, its epidemiology has not been defined in a nonselected population. We sought to
describe the incidence of, risk factors for, and outcomes associated with K. pneumoniae bacteremia.
Methods: Population-based surveillance for K. pneumoniae bacteremia was conducted in the Calgary Health
Region (population 1.2 million) from 2000 to 2007.
Results: A total of 640 episodes of K. pneumoniae bacteremia were identified for an overall annual
population incidence of 7.1 per 100,000; 174 (27%) were nosocomial, 276 (43%) were healthcareassociated community onset, and 190 (30%) were community acquired. Elderly patients and men were at
highest risk for K. pneumoniae bacteremia. Dialysis, solid-organ transplantation, chronic liver disease, and
cancer were the most important risk factors for acquiring K. pneumoniae bacteremia. Rates of resistance to
trimethoprim/sulfamethoxazole increased significantly during 2000 to 2007. The case fatality rate was 20%,
and the annual population mortality rate was 1.3 per 100,000. Increasing age, nosocomial acquisition, nonurinary and non-biliary focus of infection, and several comorbid illnesses were independently associated with
an increased risk of death.
Conclusion: This is the first population-based study to document the major burden of illness associated with
K. pneumoniae bacteremia and identifies groups at increased risk of acquiring and dying of these infections.
NosoBase n° 25619
Bactériuries à Staphylococcus
Staphylococcus aureus
aureus
concomittantes
d'une
bactériémie
compliquée
à
Pulcini C; Matta M; Mondain V; Gaudart A; Girard-Pipau F; Mainardi JL et al. Concomitant Staphylococcus
aureus bacteriuria is associated with complicated S. aureus bacteremia. The Journal of infection 2009/10;
59(4): 240-246.
Mots-clés : STAPHYLOCOCCUS AUREUS; BACTERIEMIE; BACTERIURIE; ETUDE PROSPECTIVE;
CENTRE HOSPITALIER UNIVERSITAIRE; ENDOCARDE; TRAITEMENT
Objectives: To identify factors associated with complicated Staphylococcus aureus bacteremia (SAB) in
adults.
Methods: Prospective observational multicenter study during 2 years in Nice University Hospital and during
6 months in the Hôpital Européen Georges Pompidou, Paris, including all adult inpatients with SAB
assessed by an Infectious Diseases (ID) specialist.
Results: We included 104 SAB (79 in Nice and 25 in Paris), of which 45 were complicated, including 18
endocarditis and 23 bone and joint infections. A concomitant urine sample was performed in 65% of the
cases, showing S. aureus bacteriuria 23/68 (34%) times. Blood cultures were drawn 48-96h after an
appropriate antibiotic therapy had been started in 70 of the 104 cases (67%) and were positive in 28 cases
(40%).
Conclusions: The 3 following factors were found to be associated with complicated SAB in univariate
analysis: community acquisition (56% vs 26%, P=0.002), concomitant bacteriuria (47% vs 19%, P=0.016)
and persistent bacteremia (55% vs 26%, P=0.016). This last factor was associated with endocarditis, but not
with other complications such as bone and joint infections.
NosoBase n° 25618
Mortalité des bactériémies à Staphylococcus aureus et consultation d'un infectiologue : étude
portant sur 521 patients en Allemagne
Rieg S; Peyerl-Hoffmann G; De With K; Theilacker C; Wagner D; Hubner J et al. Mortality of S. aureus
bacteremia and infectious diseases specialist consultation - a study of 521 patients in Germany. The Journal
of infection 2009/10; 59(4): 232-239.
Mots-clés : MORTALITE; STAPHYLOCOCCUS AUREUS; BACTERIEMIE; INFECTIOLOGIE; COHORTE;
CENTRE HOSPITALIER UNIVERSITAIRE; ANALYSE MULTIVARIEE; FACTEUR DE RISQUE
Objectives: To evaluate the relationship between mortality of bloodstream infection due to Staphylococcus
aureus and infectious diseases specialist consultation and other factors potentially associated with
outcomes.
Methods: A 6-year cohort study was conducted at a 1600-bed university hospital. Consecutive adult patients
with S. aureus bacteremia were assessed using a standardised data collection and review form. A new
infectious diseases service increased its consultations for S. aureus bacteremia from 33% of cases in 2002
to >80% in 2007. Infectious disease consultation and other factors potentially associated with in-hospital
mortality were analysed by multivariate logistic regression.
Results: A total of 521 patients were studied. All-cause in-hospital mortality was 22%, 90-day mortality was
32%. Factors significantly associated with in-hospital mortality in multivariate analysis were ICU admission
(OR 5.8, CI 3.5-9.7), MRSA (OR 2.6, CI 1.4-4.9), age >/=60 years (OR 2.4, CI 1.4-4.2), a diagnosis of
endocarditis (OR 2.8, CI 1.4-5.7), a non-fatal underlying disease/comorbidity according to the McCabe
classification (OR 0.2, CI 0.1-0.4), and infectious disease specialist consultation (OR 0.6, CI 0.4-1.0).
Conclusions: These data suggest that outcome of S. aureus bacteremia may be improved by an expert
consultation service.
Chirurgie
NosoBase n° 25682
Coiffes dans les blocs opératoires à flux laminaire
Gordon RJ; Bannister GC; Bowker KE; Mason AC; Cheung LL; Eames R. Headwear in laminar flow
operating theatres. The Journal of hospital infection 2009/11; 73(3): 289-291.
Mots-clés : AIR; FILTRATION; FLUX LAMINAIRE; TENUE VESTIMENTAIRE; CONTAMINATION; BLOC
OPERATOIRE
NosoBase n° 25423
Effets de la préparation cutanée de l'opéré sur les taux d'infections du site opératoire : une étude
prospective sur 3 protocoles de préparation cutanée
Swenson BR; Hedrick TI; Metzger R; Bonatti H; Pruett TI; Sawyer RG. Effects of preoperative skin
preparation on postoperative wound infection rates: a prospective study of 3 skin preparation protocols.
Infection control and hospital epidemiology 2009/10; 30(10): 964-971.
Mots-clés : PEAU; SITE OPERATOIRE; PREVENTION; TAUX; CHLORHEXIDINE; POLYVIDONE IODEE;
PRE-OPERATOIRE; ANTISEPTIQUE; PROTOCOLE
Objective: To compare the effects of different skin preparation solutions on surgical-site infection rates.
Design: Three skin preparations were compared by means of a sequential implementation design. Each
agent was adopted as the preferred modality for a 6-month period for all general surgery cases. Period 1
used a povidone-iodine scrub-paint combination (Betadine) with an isopropyl alcohol application between
these steps, period 2 used 2% chlorhexidine and 70% isopropyl alcohol (ChloraPrep), and period 3 used
iodine povacrylex in isopropyl alcohol (DuraPrep). Surgical-site infections were tracked for 30 days as part of
ongoing data collection for the National Surgical Quality Improvement Project initiative. The primary outcome
was the overall rate of surgical-site infection by 6-month period performed in an intent-to-treat manner.
Setting: Single large academic medical center.
Patients: All adult general surgery patients.
Results: The study comprised 3,209 operations. The lowest infection rate was seen in period 3, with iodine
povacrylex in isopropyl alcohol as the preferred preparation method (3.9%, compared with 6.4% for period 1
and 7.1% for period 2; P = .002). In subgroup analysis, no difference in outcomes was seen between
patients prepared with povidone-iodine scrub-paint and those prepared with iodine povacrylex in isopropyl
alcohol, but patients in both these groups had significantly lower surgical-site infection rates, compared with
rates for patients prepared with 2% chlorhexidine and 70% isopropyl alcohol (4.8% vs 8.2%; P = .001).
CONCLUSIONS: Skin preparation solution is an important factor in the prevention of surgical-site infections.
Iodophor-based compounds may be superior to chlorhexidine for this purpose in general surgery patients.
NosoBase n° 25722
Colonisation rapide par des staphylocoques à coagulase négative résistant à la méticilline après
chirurgie
Zingg W; Demartines N; Imhof A; Senn G; Ruef C. Rapid colonization with methicillin-resistant coagulasenegative staphylococci after surgery. World journal of surgery 2009/10; 33(10): 2058-2062.
Mots-clés : COLONISATION; METICILLINO-RESISTANCE
Background: Antimicrobial resistance may compromise the efficacy of antibiotic prophylaxis before surgery.
The aim of this study was to measure susceptibility and clonal distribution of coagulase-negative
staphylococci (CoNS) colonizing the skin around the surgery access site before and after the procedure.
Methods: From March to September 2004, a series of 140 patients undergoing elective major abdominal
surgery were screened for CoNS colonization at admission and 5 days after surgery. All isolates were tested
for antibiotic susceptibility and genotyped by pulsed-field gel electrophoresis (PFGE).
Results: Colonization rates with CoNS at admission and after surgery were 85% and 55%, respectively. The
methicillin-resistant CoNS rate increased from 20% at admission to 47% after surgery (P = 0.001). The
PFGE pattern after surgery revealed more patients colonized with identical clones: 8/140 patients (8/119
strains) and 26/140 patients (26/77 strains), respectively (P < 0.001).
Conclusions: Our results suggest rapid recolonization of disinfected skin by resistant nosocomial CoNS.
Larger studies, preferably among orthopedic or cardiovascular patients, are required to clarify whether
standard antibiotic prophylaxis with first- or second-generation cephalosporins for CoNS infections may be
compromised if the patient requires an additional intervention 5 days or more after the initial surgery.
Environnement
NosoBase n° 25677
A propos de la survie des bactéries de la salive sur les dossiers des patients
Hope CK; Malton LV. Concerning the survival of saliva-borne oral bacteria on patient notes. The Journal of
hospital infection 2009/11; 73(3): 282-283.
Mots-clés : ODONTOLOGIE; CONTAMINATION; CAVITE BUCCALE
NosoBase n° 25565
Staphylococcus aureus méticillino-résistant et Acinetobacter baumannii sur des surfaces
d'ordinateurs de services hospitaliers et association aux isolats cliniques
Lu PL; Siu LK; Chen TC; Ma L; Chiang WG; Chen YH et al. Methicillin-resistant Staphylococcus aureus and
Acinetobacter baumannii on computer interface surfaces of hospital wards and association with clinical
isolates. BMC infectious diseases 2009/10; in press: 28 pages.
Mots-clés : METICILLINO-RESISTANCE; STAPHYLOCOCCUS AUREUS; ACINETOBACTER; SURFACE;
ORDINATEUR; ANTIBIORESISTANCE; CONTAMINATION; ETUDE TRANSVERSALE; SURVEILLANCE
Background: Computer keyboards and mice are potential reservoirs of nosocomial pathogens, but routine
disinfection for non-water-proof computer devices is a problem. With better hand hygiene compliance of
health-care workers (HCWs), the impact of these potential sources of contamination on clinical infection
needs to be clarified.
Methods: This study was conducted in a 1600-bed medical center of southern Taiwan with 47 wards and
282 computers. With education and monitoring program of hand hygiene for HCWs, the average compliance
rate was 74% before our surveillance. We investigated the association of methicillin-resistant
Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Acinetobacter baumannii, three leading
hospital-acquired pathogens, from ward computer keyboards, mice and from clinical isolates in non-outbreak
period by pulsed field gel electrophoresis and antibiogram.
Results: Our results revealed a 17.4% (49/282) contamination rate of these computer devices by S. aureus,
Acinetobacter spp. or Pseudomonas spp. The contamination rates of MRSA and A. baumannii in the ward
computers were 1.1% and 4.3%, respectively. No P. aeruginosa was isolated. All isolates from computers
and clinical specimens at the same ward showed different pulsotypes. However, A. baumannii isolates on
two ward computers had the same pulsotype.
Conclusion: With good hand hygiene compliance, we found relatively low contamination rates of MRSA, P.
aeruginosa and A. baumannii on ward computer interface, and without further contribution to nosocomial
infection. Our results suggested no necessity of routine culture surveillance in non-outbreak situation.
Grippe
NosoBase n° 25666
Approche coordonnée de la vaccination contre la grippe du personnel de santé dans une région
d'offre de soins de santé
Ballestas T; Mcevoy SP; Doyle J. Co-ordinated approach to healthcare worker influenza vaccination in an
area health service. The Journal of hospital infection 2009/11; 73(3): 203-209.
Mots-clés : VIRUS; GRIPPE; VACCIN; PERSONNEL; OBSERVANCE; TAUX; ETUDE TRANSVERSALE;
QUESTIONNAIRE; INTERNET
To increase local influenza vaccination uptake among healthcare workers (HCWs), a co-ordinated, areawide influenza vaccination campaign was undertaken in 2008 for five hospitals in the South Metropolitan
Area Health Service of Perth, Western Australia (WA). The programme included standardised marketing and
data collection, with a consent form completed by each recipient. Denominator data were obtained from the
WA Department of Health's staff database. Vaccination coverage at each hospital was calculated and
compared with that of 2007, with predictors for vaccination determined using a follow-up cross-sectional
survey. A total of 6387 influenza vaccinations were administered. The coverage rate was above 55% in all
but one hospital (range: 48.8-76.5%) whereas in 2007 no hospital achieved 55% (range: 29-51%). Allied
health professionals attained the highest coverage (57.7%), followed by doctors (51.9%), nurses (49.6%)
and patient support staff (48.6%). Of HCWs who worked half-time or more, 58.8% were vaccinated. The
main reasons for vaccination were to prevent influenza, limit spread, and the programme's availability. The
survey revealed that HCWs who perceived that they were susceptible to influenza, that it was a serious
disease and that immunisation was effective and important were significantly more likely to be vaccinated.
An area-wide approach to HCW influenza vaccination can substantially improve uptake. Regular working
party meetings, consistent marketing, standardised data collection and analysis, and senior management
support were key elements and could be used by others to attain good vaccination coverage among HCWs.
NosoBase n° 25652
Disparités des taux de couverture vaccinale contre la grippe par groupes ciblés dans cinq pays
européens : tendances sur sept saisons consécutives
Blank PR; Schwenkglenks M; Szucs TD. Disparities in influenza vaccination coverage rates by target group
in five european countries: trends over seven consecutive seasons. Infection 2009/10; 37(5): 390-400.
Mots-clés : VACCIN; GRIPPE; AGE; OBSERVANCE; TAUX
Background: The primary objective of this study was to measure influenza vaccination coverage rates in the
general population, including children, and in high-risk groups of five European countries during the season
2007/2008. An additional aim was to analyze coverage trends over seven consecutive seasons and to gain
an understanding of the primary drivers and barriers to immunization.
Methods: Community-based telephone and mail surveys have been conducted in the UK, Germany, Italy,
France, and Spain, yearly, since 2001/2002. Approximately 2,000 individuals per country and season were
interviewed who were considered to be representative of the adult population aged 14 years and older. Data
on the vaccination status of children were obtained by proxy interviews. The questionnaire used was
essentially the same for all seven seasons. Five target groups were identified for the study: (1) persons aged
>/= 65 years; (2) elderly suffering from a chronic illness; (3) patients suffering from a chronic illness; (4)
persons working in the health care sector; (5) children.
Results: In the season 2007/2008, vaccination coverage rates in the general population remained stable in
Germany. Compared to the coverage rates of the previous season, increases of 3.7%, 2.0%, and 1.8% were
observed for the UK, Spain, and France, respectively, while a decrease of -1.5% was observed for Italy.
Across all five countries, vaccination rates in the predefined target groups decreased to some extent
(elderly) or increased slightly (chronically ill and health care workers). Vaccination rates among children
varied strongly between countries and ranged from 6.1% in UK to 19.3% in Germany. The most powerful
motivation for getting vaccinated in all countries was advice from a family doctor (58.6%) and the perception
of influenza as a serious illness (51.9%). The major reasons why individuals did not become vaccinated
were (1) the feeling of not being likely to catch influenza (39.5%) and (2) never having considered the option
of being vaccinated (35.8%).
Conclusions: The change in general influenza vaccination coverage in the 2007/2008 season compared to
the previous season was small, but decreases were seen in some target groups. The underlying motivations
for and against vaccination did not substantially change. An effort to activate those driving forces that would
encourage vaccination as well as dealing with barriers that tend to prevent it may help enhance coverage
rates in Europe in the future.
NosoBase n° 25665
La grippe H1N1 est arrivée
Burns SM. H1N1 influenza is here. The Journal of hospital infection 2009/11; 73(3): 200-202.
Mots-clés : GRIPPE; EPIDEMIE; RECOMMANDATION; PREVENTION; PERSONNEL
On 11 June WHO announced that the spread of H1N1 had reached pandemic phase 6. Since then countries
around the world have increased their planning and preparedness for the continuing pandemic. Guidelines
have been issued and circulated but confusion continues over their interpretation. We need to remind
ourselves of the principles behind control measures and educate and reinforce standard infection control
procedures in the acute hospital setting.
NosoBase n° 25650
Contre la nouvelle grippe H1N1 (grippe porcine) : vacciner ou ne pas vacciner. Telle est la question
actuelle !
Doerr HW; Allwinn R; Cinatl J. Against the new H1N1 influenza (swine influenza): vaccinate or don't
vaccinate (all)? That is currently the question! Infection 2009/10; 37(5): 379-380.
Mots-clés : VACCIN; GRIPPE; VIRUS INFLUENZA TYPE A
NosoBase n° 25651
Réveil du virus de la grippe A H1N1 - Pandémie au virus H1N1/09
Michaelis M; Doerr HW; CINATL J. An influenza A H1N1 virus revival - pandemic H1N1/09 virus. Infection
2009/10; 37(5): 381-389.
Mots-clés : VIRUS; GRIPPE; EPIDEMIE; EPIDEMIOLOGIE; TRANSMISSION; VACCIN; TRAITEMENT;
ANTIVIRAL; PREVENTION
In April 2009, a novel H1N1 influenza A virus, the so-called pandemic H1N1/09 virus (former designations
include swine influenza, novel influenza, swine-origin influenza A [H1N1] virus [S-OIV], Mexican flu, North
American Flu) was identified in Mexico. The virus has since spread throughout the world and caused an
influenza pandemic as defined by the criteria of the World Health Organization. This represents the first
influenza A virus pandemic since the emergence of H3N2 ("Hong Kong" Flu) in 1968. Vaccine production
has started, and vaccines are expected to become available during the course of 2009. Although the
pandemic H1N1/09 virus originates from the triple-reassortant swine influenza (H1) virus circulating in North
American pigs, it is not epidemic in pigs. Although the H1N1/09 virus pandemic is currently mild, concerns
remain that it may become more aggressive during spreading. The distribution of proper information to the
public on the status of the H1N1/09 virus pandemic will be important to achieve a broad awareness of the
potential risks and the optimum code of behavior during the pandemic. Here, the features of pandemic
H1N1/09 virus are discussed within the framework of knowledge gained from previous influenza A virus
pandemics.
Hémodialyse
NosoBase n° 25762
Infections liées aux cathéters chez des patients hémodialysés
Nabi Z; Anwar S; Barhamein M; Al Mukdad H; El Nassri A. Catheter related infection in hemodialysis
patients. Saudi journal of kidney diseases and transplantation 2009/12; 20(6): 1091-1095.
Mots-clés : HEMODIALYSE; ETUDE PROSPECTIVE; CATHETER; FACTEUR DE RISQUE;
HEMOCULTURE; STAPHYLOCOCCUS AUREUS; ANTIBIORESISTANCE; SYNDROME SEPTIQUE
To determine the frequency of hemodialysis (HD) catheter related infection, causative microorganisms and
predisposing factors contributing to these infections at our center, we conducted a prospective study in 2007
involving 57 (45.6 % males) patients in whom a temporary catheter was inserted for HD. The patients were
followed for one month to document any episodes of hemodialysis catheter related infection (HCRI). There
were 11 (19.36 %) patients who developed HCRI proven by blood culture; 5 patients were infected with
more than one organism. Staphylococcus Coagulase negative and Staphylococcus aureus (S. aureus)
remain the most common pathogens. All the organisms were sensitive to antibiotics administered
empirically, however, 3 patients developed multiple resistant S. aureus (MRSA). All the infected patients
experienced previous episodes of HCRI, which formed a risk factor in addition to low albumin when
compared to the non-infected group (P=0.024 and P=0.001, respectively). We conclude that the rate of
HCRI and the causative organisms found in our study is comparable to previous reports. We still need to
adopt measures to minimize the use of temporary vascular accesses by creation of fistulas in a timely
fashion.
Hépatite C
NosoBase n° 25599
Transmission associée aux soins du virus de l'hépatite C parmi des patients d'un centre de
transplantation d'organes abdominaux
Thompson ND; Hellinger WC; Kay RS; Cohen L; Ragan P; Voss RA. Healthcare-associated hepatitis C
virus transmission among patients in an abdominal organ transplant center. Transplant infectious disease
2009/08; 11(4): 324-329.
Mots-clés : HEPATITE C; VIRUS; TRANSMISSION; TRANSPLANTATION HEPATIQUE; EPIDEMIOLOGIE;
BIOLOGIE MOLECULAIRE
Background: De novo hepatitis C virus (HCV) infection among transplant patients is rarely recognized but
can have severe consequences. We investigated the scope, source, and mode of HCV transmission within a
transplant center after incident HCV infection was identified in 2 patients who had liver transplantation in late
2006.
Methods: Patients were interviewed, and transplant logs, medical records, and staff practices were reviewed
to identify opportunities for HCV transmission. Infection via receipt of blood or organs was evaluated.
Molecular epidemiology was used to determine the relatedness between persons with incident and chronic
HCV infection.
Results: HCV from infected blood or organ donors was ruled out. Among the 308 patients who underwent
transplant in 2006, no additional incident HCV infections were identified. Eighty-five (28%) had pretransplant chronic HCV infection; 13 were considered possible HCV source patients based upon shared
days on the inpatient unit, nursing assignment, or invasive procedures in common with incident HCV casepatients. Viral isolates from 1 HCV source patient and 1 incident case-patient were found to be
highly related by quasispecies analysis, confirming patient-to-patient HCV transmission. Possible modes of
transmission identified were the improper use of multidose vials, sharing of blood-contaminated
glucometers, and touch contamination.
Conclusion: Sporadic transmission or endemic levels of HCV transmission might be overlooked in a setting
with high HCV prevalence, such as liver transplant units, where multiple, repeated opportunities for patientto-patient HCV transmission can occur. Surveillance through pre- and post-transplant screening is
necessary to identify incident HCV infection in this setting. Constant, meticulous attention must be paid to
maintaining aseptic technique and good infection control practices to eliminate HCV transmission
opportunities.
Hygiène des mains
NosoBase n° 25419
L'hygiène des mains à l'eau et au savon est supérieure à la friction hydro-alcoolique et aux lingettes
antiseptiques pour l'élimination du Clostridium difficile
Oughton MT; Loo VG; Dendukuri N; Fenn S; Libman MD. Hand hygiene with soap and water is superior to
alcohol rub and antiseptic wipes for removal of Clostridium difficile. Infection control and hospital
epidemiology 2009/10; 30(10): 939-944.
Mots-clés :LAVAGE DES MAINS; SAVON DOUX; SAVON DESINFECTANT; TRAITEMENT HYGIENIQUE
DES MAINS PAR FICTION; CLOSTRIDIUM DIFFICILE; EAU; EAU CHAUDE; EVALUATION
Objective: To evaluate common hand hygiene methods for efficacy in removing Clostridium difficile.
Design: Randomized crossover comparison among 10 volunteers with hands experimentally contaminated
by nontoxigenic C. difficile.
Methods: Interventions included warm water with plain soap, cold water with plain soap, warm water with
antibacterial soap, antiseptic hand wipes, alcohol-based handrub, and a control involving no intervention. All
interventions were evaluated for mean reduction in colony-forming units (CFUs) under 2 contamination
protocols: "whole hand" and "palmar surface." Results were analyzed according to a Bayesian approach, by
using hierarchical models adjusted for multiple observations. RESULTS: Under the whole-hand protocol,
the greatest adjusted mean reductions were achieved by warm water with plain soap (2.14 log(10) CFU/mL
[95% credible interval (CrI), 1.74-2.54 log(10) CFU/mL]), cold water with plain soap (1.88 log(10) CFU/mL
[95% CrI, 1.48-2.28 log(10) CFU/mL), and warm water with antibacterial soap (1.51 log(10) CFU/mL [95%
CrI, 1.12-1.91 log(10) CFU/mL]), followed by antiseptic hand wipes (0.57 log(10) CFU/mL [95% CrI, 0.170.96 log(10) CFU/mL]). Alcohol-based handrub (0.06 log(10) CFU/mL [95% CrI, -0.34 to 0.45 log(10)
CFU/mL]) was equivalent to no intervention. Under the palmar surface protocol, warm water with plain soap,
cold water with plain soap, and warm water with antibacterial soap again yielded the greatest mean
reductions, followed by antiseptic hand wipes (26.6, 26.6, 26.6, and 21.9 CFUs per plate, respectively),
when compared with alcohol-based handrub. Hypothenar (odds ratio, 10.98 [95% CrI, 1.96-37.65]) and
thenar (odds ratio, 6.99 [95% CrI, 1.25-23.41]) surfaces were more likely than fingertips to remain heavily
contaminated after handwashing.
Conclusions: Handwashing with soap and water showed the greatest efficacy in removing C. difficile and
should be performed preferentially over the use of alcohol-based handrubs when contact with C. difficile is
suspected or likely.
NosoBase n° 25664
Méthodes destinées à évaluer les activités microbicides des produits utilisés pour le lavage des
mains et la désinfection des mains par friction
Rotter M; Sattar S; Dharan S; Allegranzi B; Mathai E; Pittet D. Methods to evaluate the microbicidal activities
of hand-rub and hand-wash agents. The Journal of hospital infection 2009/11; 73(3): 191-199.
Mots-clés : HYGIENE DES MAINS; METHODOLOGIE; SOLUTION HYDROALCOOLIQUE; NORME;
SAVON DOUX; TEST
In vitro carrier tests, suspension tests, time-kill curves, and determinations of minimum inhibitory
concentrations to evaluate the microbicidal activities of hand antiseptics provide only a preliminary indication
of the antimicrobial spectrum and speed of action of a given formulation. Ex vivo testing with human or
animal skin at human skin temperature and at contact times reflecting field conditions may give a better
indication of a formulation's ability to tackle hand-transmitted pathogens. Field testing of hands for levels of
skin microbiota before and after antisepsis may be easier to perform, but it is subject to many uncontrollable
factors. Whereas randomised clinical trials may be the ultimate approach to assess the effectiveness of
hand hygiene protocols and products in preventing microbial cross-transmission and, ultimately, infections,
they can be prohibitively expensive, time-consuming, difficult to design, and therefore impractical. Hence,
the primary emphasis should be on in vivo testing on human hands, using a well-designed protocol that
closely simulates the recommended field use of the formulation, and possibly followed by clinical studies.
The use of these method is the most likely to yield useful data on the potential of a formulation to interrupt
the spread of pathogens transmitted by hands in healthcare settings. This review provides a critical
assessment of the methods currently used to meet regulatory requirements for hand antiseptics in Europe
and North America.
Pédiatrie
NosoBase n° 25434
Utilisation de cathéters centraux insérés périphériquement pour prévenir les infections systémiques
sur cathéter chez les enfants
Goes-Silva E; Abreu TF; Frota A; Pessoa-Silva CL; Cunha A; Hofer CB. Use of peripherally inserted central
catheters to prevent catheter-associated bloodstream infection in children. Infection control and hospital
epidemiology 2009/10; 30(10): 1024-1028.
Mots-clés : CATHETER VEINEUX CENTRAL; PREVENTION; PEDIATRIE; BACTERIEMIE; SOIN
INTENSIF; ETUDE PROSPECTIVE; TAUX; FACTEUR DE RISQUE
Personnel
NosoBase n° 25432
Transmission d’infections bactériennes aux personnels de santé lors de soins respiratoires et
intubations de patients atteints de pneumonie sévère
Baba H; Iinuma Y; Imaizumi K; Hasegawa Y; Hasegawa T; Ohta M; et al. Transmission of bacterial
infections to healthcare workers during intubation and respiratory care of patients with severe pneumonia.
Infection control and hospital epidemiology 2009/10; 30(10): 1019-1021.
Mot-clés : TRANSMISSION; PNEUMONIE; SOIN RESPIRATOIRE; INTUBATION; RISQUE
PROFESSIONNEL; STREPTOCOCCUS GROUPE A; INFIRMIER
Exposure of healthcare workers to patients with rapidly fatal infections invariably raises concerns regarding
the risk of occupational acquisition. We describe acquisition of Streptococcus pyogenes by 2 nurses from a
patient with fatal pneumonia and review previously reported cases of transmission of bacterial pathogens
from patients with pneumonia to healthcare workers.
NosoBase n° 25670
Un cadre éthique est-il nécessaire pour la lutte contre le risque infectieux à l'hôpital ?
Millar M. Do we need an ethical framework for hospital infection control? The Journal of hospital infection
2009/11; 73(3): 232-238.
Mots-clés : CONTROLE; PERSONNEL; DEONTOLOGIE
Strategies for the control of the spread of infection in hospitals may lead to constraints on individual
autonomy, freedom of movement, or contact with others. Codes of (ethical) practice for healthcare
professionals tend to emphasise responsibilities to individual patients. Ethical frameworks for public health
focus on groups of individuals (populations), the majority of whom are relatively healthy and empowered.
Hospital infection control professionals must take account of both of these perspectives, sensitive to the care
of infected and potentially infectious individuals, while protecting the vulnerable and relatively dependent
population of hospital patients from further compromise to their health. A number of frameworks for an ethics
of public health have been proposed over the last few years but there are sufficient differences in ethical
considerations between collective interventions that aim to protect and promote the health of the public and
interventions taken in the context of hospital infection control to justify a distinctive ethics of hospital infection
control. Professional bodies may be best placed to lead the development of such a framework.
NosoBase n° 25429
La protection immunitaire contre les maladies à prévention vaccinale n’est pas optimale chez des
internes et des élèves infirmiers
Pavlopoulou ID; Daikos GI; Tzivaras A; Bozas E; Kosmidis C; Tsoumakas C; et al. Medical and nursing
students with suboptimal protective immunity against vaccine-preventable diseases. Infection control and
hospital epidemiology 2009/10; 30(10): 1006-1011.
Mots-clés :
VACCIN; VIRUS; PREVENTION; RECOMMANDATION; OBSERVANCE; ETUDIANT;
MEDECIN; INFIRMIER; ETUDE PROSPECTIVE; TRANSMISSION; DIAGNOSTIC; SEROLOGIQUE;
ANTICORPS; BORDETELLA PERTUSSIS; CLOSTRIDIUM TETANI; HEPATITE A; HEPATITE B;
OREILLONS; ROUGEOLE; RUBEOLE; VARICELLE
Objectives: Medical and nursing students (hereafter referred to as "healthcare students") are at risk of
contracting and transmitting infectious diseases in a hospital setting. The aim of our study was to evaluate
the vaccination history of healthcare students and their serologic immunity against vaccine-preventable
diseases.
Design: Prospective cohort study.
Setting: A tertiary care children's hospital in Athens, Greece, which is affiliated with the University of Athens.
Methods: Healthcare students were recruited during April through November 2007. The information obtained
from these students during personal interviews included demographics and whether there was a history of
varicella, measles, mumps, rubella, and/or hepatitis A or B virus infection. Vaccination history and
documentation of disease were abstracted from available medical records. Serum antibodies against the
above-mentioned viral agents were determined by use of an enzyme-linked immunosorbent assay.
Seronegative students and those with immunization gaps were referred to local vaccination clinics, and
compliance was assessed 3 months later.
Results: A total of 187 healthcare students were recruited, 131 (70.1%) of whom provided complete
documentation of vaccination history. Adequate immunity against diphtheria and tetanus was documented
for 55 (37.2%) and 73 (49.3%) of the 148 participants, respectively, whereas age-appropriate vaccination
against pertussis, diphtheria, tetanus, and poliomyelitis was noted for 138 (93.2%), 147 (99.3%), 147
(99.3%), and 147 (99.3%) healthcare students, respectively. Of 185 healthcare students, 171 (92.4%) were
immune to varicella. Of 182 healthcare students, 179 (98.4%) were immune to measles, 163 (89.6%) were
immune to mumps, and 176 (96.7%) were immune to rubella. Of 179 healthcare students, 151 (84.4%) were
immune to hepatitis B virus. Of 178 healthcare students, 26 (14.6%) were immune to hepatitis A virus.
Antibodies (10 IU/L or higher) to hepatitis B surface antigen were detected for 151 (84.4%) of 179 healthcare
students, and antibodies (10 IU/L or higher) to hepatitis A virus were detected for 26 (14.6%) of 178
healthcare students. Fewer than 30% of participants were in full compliance with recommended
vaccinations.
Conclusions: We have determined that there is a certain proportion of healthcare students who are
susceptible to certain vaccine-preventable diseases. The development of an appropriate vaccination
strategy is required to decrease the risk of transmission in a hospital setting.
NosoBase n° 25536
Evaluation des connaissances et des pratiques du personnel infirmier concernant les mesures de
lutte contre le risque infectieux dans un centre hospitalier universitaire
Taneja J. Evaluation of knowledge and practice amongst nursing staff toward infection control measures in a
tertiary care hospital in India. The Canadian journal of infection control 2009; 24(2): 104-107.
Mots-clés : CONNAISSANCE; PERSONNEL; FORMATION; QUESTIONNAIRE; PRATIQUE; INFIRMIER
Purpose: A study to assess the level of knowledge and practice of 100 staff nurses on infection control
measures was carried out in a tertiary care center.
Method: A structured questionnaire was used to collect the data.
Results: The mean knowledge of staff nurses regarding infection control measures was 75.5% and the
mean reported infection control practice was 57.5%. After conducting exhaustive lectures on infection
control related topics, a significant decline in the hospital-acquired infection (HAIs) rates was seen in the
high-risk areas.
Conclusion: Training of nursing staff is needed to improve knowledge and practice in infection control.
NosoBase n° 25678
Survie des bactéries sur les tenues de travail en lien avec la gestion du risque dans les cliniques
dentaires
Van Der Reijden WA; Rood M; Heijers JM; Vandenbroucke-Grauls C; De Soet JJ. Survival of bacteria on
uniforms in relation to risk management in dental clinics. The Journal of hospital infection 2009/11; 73(3):
283-285.
Mots-clés : BACTERIE; RISQUE; TENUE VESTIMENTAIRE; ODONTOLOGIE
Pneumonie
NosoBase n° 25698
Doripénème dans le traitement des pneumonies acquises sous ventilation mécanique
Luyt CE; Chastre J. Doripenem in treatment of mechanical ventilation acquired pneumonia. Réanimation
2009/09; 18(Supplément 2): S209-S213.
Mots-clés : DORIPENEME; PNEUMONIE; VENTILATION ASSISTEE; PSEUDOMONAS AERUGINOSA;
PIPERACILLINE; IMIPENEME; KLEBSIELLA; PNEUMONIAE; TAZOBACTAM
Le doripénème est un nouveau carbapénème synthétique dont une des principales caractéristiques par
rapport aux autres carbapénèmes est une plus grande stabilité. Si l’efficacité du doripénème dans les
infections respiratoires sévères n’est plus à démontrer, deux études randomisées récentes l’ont évalué dans
le traitement des pneumonies acquises sous ventilation mécanique. Dans la première, le doripénème n’était
pas inférieur à l’association pipéraciline/tazobactam dans les pneumonies précoces (< 5 jours de ventilation
mécanique) et les pneumonies nosocomiales des patients non ventilés. Dans la deuxième étude, le
doripénème était comparé à l’imipénème chez des patients présentant une pneumonie acquise sous
ventilation mécanique. Là encore, le doripénème n’était pas inférieur à l’imipénème. En conclusion, le
doripénème est un nouveau carbapénème qui possède une meilleure activité in vitro contre Pseudomonas
aeruginosa que les autres carbapénèmes, et dont l’efficacité clinique n’est pas inférieure ni à l’imipénème, ni
à l’association pipéraciline/tazobactam. Il pourrait donc être proposé en première intention dans le
traitement des pneumonies acquises sous ventilation mécanique.
NosoBase n° 25635
Diagnostic des pneumonies acquises sous ventilation
Medford A; Husain SA; Turki HM; Millar AB. Diagnosis of ventilator-associated pneumonia. Journal of critical
care 2009/09; 24(3): 473.e1-473.e6.
Mots-clés : PNEUMONIE; DIAGNOSTIC; VENTILATION ASSISTEE; PRELEVEMENT; LAVAGE
BRONCHO-ALVEOLAIRE; ETUDE PROSPECTIVE; SOIN INTENSIF
Introduction: Ventilator-associated pneumonia (VAP) is difficult to diagnose. Recent data suggest
quantitative endotracheal aspirate (ETA) may be noninferior diagnostically to quantitative bronchoalveolar
lavage (BAL). We hypothesized this would be the case.
Methods: Blind quantitative ETA and BAL were performed on 150 consecutive ventilated patients with
suspected VAP in a prospective single-centre medical intensive care unit study over a 2-year inclusion
period. Patients were either antibiotic-naive or antibiotic-free for 72 hours. Diagnostic yield, Gram stain and
culture results, and impact on antibiotic therapy were assessed. The independent impact of a positive BAL
or ETA result on ventilator settings and 28-day mortality was calculated. The BAL/ETA safety was assessed
hemodynamically.
Results: Bronchoalveolar lavage had significantly higher diagnostic yield (49.3% vs 34.0%, P = .01), more
frequent impact on antibiotic therapy (usually de-escalation) (48.0% vs 32.7%, P = .01), and greater
sensitivity (64.1% vs 42.6%, P = .0003) than ETA. There was moderate intertest agreement and no
difference in specificity and positive and negative predictive values. A positive BAL or ETA result
did not independently alter the frequency of ventilator changes or 28-day mortality. Both procedures were
well tolerated.
Conclusion: Quantitative BAL is safe and has greater diagnostic utility than ETA for VAP facilitates
de-escalation. This study provides support for quantitative BAL in VAP diagnosis.
NosoBase n° 25672
Nouvelle identification des valeurs aberrantes et des taux de pneumonies acquises sous ventilation
de 2005 à 2007 dans le réseau allemand de surveillance des infections nosocomiales (NISS)
Meyer E; Sohr D; Gastmeier P; Geffers C. New identification of outliers and ventilator-associated pneumonia
rates from 2005 to 2007 within the German Nosocomial Infection Surveillance System. The Journal of
hospital infection 2009/11; 73(3): 246-252.
Mots-clés :
RESEAU;
TAUX;
PNEUMONIE;
VENTILATION
ASSISTEE;
SURVEILLANCE;
METHODOLOGIE
This study presents data for ventilator use and ventilator-associated pneumonia (VAP) rates from the
German hospital surveillance system for nosocomial infections (KISS: Krankenhaus Infektions Surveillance
System). New Centers for Disease Control and Prevention (CDC) definitions became effective during 2005
and we describe the new method used by KISS to determine individual units with data at extreme ranges.
The number of VAP cases per 1000 device-days was calculated and a new visual method, specifically
funnel plots, was introduced to identify outliers. The VAP rate will be highly influenced by chance variability if
only a few VAP cases are observed during a low number of ventilator-days. Funnel plots take this
relationship between event rate and volume of cases into account. A total of 391 intensive care units (ICUs)
reported surveillance data from 8 86 816 patients and included 6896 VAPs and 3 113 983 patient-days for
the period January 2005 to December 2007. The mean VAP rate according to the new CDC definitions was
5.5 cases per 1000 ventilator-days (median: 4.4). The mean ventilator use in all ICUs was 35.7 (median:
29.3). Funnel plots identified 14.3% as outliers; 34 of them as high, and 22 as low, outliers. Since 2008,
visual feedback to the KISS ICUs has been supplied by funnel plots. These are less prone to
misinterpretation than histograms and they indicate when investigation is required for increasing VAP.
NosoBase n° 25643
Efficacité d'un lavage broncho-alvéolaire bilatéral pour le diagnostic des pneumonies acquises sous
ventilation
Zaccard CR; Schell RF; Spiegel CA. Efficacy of bilateral bronchoalveolar lavage for diagnosis of ventilatorassociated pneumonia. Journal of clinical microbiology 2009/09; 47(9): 2918-2924.
Mots-clés : EFFICACITE; DIAGNOSTIC; PNEUMONIE; VENTILATION ASSISTEE; PRELEVEMENT;
LAVAGE BRONCHO-ALVEOLAIRE; ETUDE RETROSPECTIVE
Ventilator-associated pneumonia (VAP) is a common nosocomial infection causing significant morbidity and
mortality. The goal of this study was to determine the efficacy of bilateral versus unilateral bronchoalveolar
lavage (BAL) for the detection of the causative bacterial agents of VAP. We retrospectively studied the
quantitative bacterial cultures of 399 BAL sample pairs collected from 287 mechanically ventilated patients
over a 5-year period at a U.S. tertiary-care teaching hospital. Trauma was the underlying illness in 69% of
patients. No evidence of bacterial infection was found in 226 BAL pairs (56.6%). Among 173 positive BAL
sample pairs, significant bacterial counts were detected exclusively in 6.4% of left-lung and 12.1% of rightlung samples. In contrast, 81.5% of positive sample pairs had significant bacterial counts in both lungs. All
bacteria recovered at significant concentrations from bilateral samples would have been detected in a
unilateral right-lung sample in 89% of positive sample pairs. Unilateral sampling would have failed to recover
one or more significant isolates in 11% of positive pairs had only the right lung been sampled and in 16.7%
had only the left lung been sampled. Our study shows that preferential sampling of the right lung improves
the diagnostic efficacy of unilateral BAL for the detection of the etiologic agents of VAP. If bilateral sampling
is performed, our results also indicate that pooling left- and right-lung samples for a single quantitative
culture is comparable to processing samples individually.
Réanimation
NosoBase n° 25644
Impact du sexe sur l'évolution des patients de réanimation présentant des infections nosocomiales
Combes A; Luyt CE; Trouillet JL; Nieszkowska A; Chastre J. Gender impact on the outcomes of critically ill
patients with nosocomial infections. Critical care medicine 2009/09; 37(9): 2506-2511.
Mots-clés : SEXE; FACTEUR DE RISQUE; SOIN INTENSIF; PNEUMONIE; BACTERIEMIE; CATHETER;
INFECTION URINAIRE; COHORTE; ETUDE RETROSPECTIVE; ANALYSE MULTIVARIEE; MORTALITE
Objectives: To investigate gender impact on the outcomes of severe nosocomial infections (pneumonia,
bacteremia, catheter-related bloodstream infections, poststernotomy mediastinitis, urinary infections)
occurring in a large cohort of patients hospitalized in a medical-surgical intensive care unit. Highly
controversial data exist regarding gender-related differences in outcomes of severe nosocomial infections,
reflecting potential confounders related to case-mixes or heterogeneity of populations evaluated.
Design: Retrospective study of patients admitted to our intensive care unit. Multivariable logistic
regression-analysis was used to control for confounders in the evaluation of gender impact on intensive care
unit death post nosocomial infections.
Setting: An 18-bed tertiary referral medical-surgicalintensive care unit in a teaching hospital.
Patients: Mixed population of patients who developed nosocomial infections in the intensive care unit.
Measurements and main results: Among the 5081 patients admitted to our intensive care unit from 1995 to
2004, 1341 (34% women) developed nosocomial infections. Pneumonia and mediastinitis were more
frequent in men (51% vs. 44%, p = .01 and 29% vs. 22%, p = .01, respectively) whereas urinary
infections predominated for women (46% vs. 24%, p < .001). Durations of mechanical ventilation and
intensive care unit stays and treatment intensity did not differ between genders. However, intensive care unit
mortality was higher for women (37% vs. 32%, p = .06) and this excess mortality was statistically significant
(odds ratio = 1.50, 95% Confidence Interval = 1.11-2.03), after controlling for other independent risk factors
of intensive care unit death. Compared with those observed for men of the same subgroup, crude ICU death
rates were significantly higher for women who developed pneumonia, who were <50 yrs old or had
undergone heart surgery before intensive care unit admission. However, multivariable analyses retained
feminine gender as significantly associated with mortality only for the last subgroup.
Conclusions: Female intensive care unit patients developing nosocomial infections seem to be at increased
risk of intensive care unit mortality, after carefully controlling for other prognostic factors. Further studies
are needed to elucidate the pathophysiology underlying this gender-related difference, to devise tailored
gender-specific therapies that might improve outcomes.
NosoBase n° 25679
Origine de clones épidémiques d'Acinetobacter en réanimation
Damjanovic V; Taylor N; Van Saene H. Origin of epidemic clones of acinetobacter in the critically ill.
The Journal of hospital infection 2009/11; 73(3): 285-286.
Mots-clés : EPIDEMIE; ACINETOBACTER; SOIN INTENSIF
NosoBase n° 25422
Efficacité de la toilette quotidienne des patients au gluconate de chlorhexidine pour la prévention
des infections en réanimation médicale
Popovich KJ; Hota B; Hayes R; Weinstein RA; Hayden MK. Effectiveness of routine patient cleansing with
chlorhexidine gluconate for infection prevention in the medical intensive care unit. Infection control and
hospital epidemiology 2009/10; 30(10): 959-963.
Mots-clés : CHLORHEXIDINE; PREVENTION; SOIN INTENSIF; CATHETER VEINEUX CENTRAL;
BACTERIEMIE
Background: Controlled studies that took place in medical intensive care units (MICUs) have demonstrated
that bathing patients with chlorhexidine gluconate (CHG) can reduce skin colonization with potential
pathogens and can lessen the risk of central venous catheter (CVC)-associated bloodstream infection (BSI).
Objective: To examine, without oversight of practice by research study staff, the effectiveness or real-world
effect of patient cleansing with CHG on rates of CVC-associated BSI. DESIGN: In the fall of 2005, the MICU
at Rush University Medical Center discontinued bathing patients daily with soap and water and substituted
skin cleansing with no-rinse, 2% CHG-impregnated cloths. This change was a clinical management decision
without research input.
Setting: A 21-bed MICU at Rush University Medical Center.
Patients: Patients hospitalized in the MICU during the period from September 2004 through October 2006.
Methods: In a pre-post study design, we gathered data from administrative and laboratory databases,
infection control practitioner logs, and patient medical charts to compare rates of CVC-associated BSI and
blood culture contamination between the baseline soap-and-water bathing period (September 2004-October
2005) and the CHG bathing period (November 2005-October 2006). Rates of secondary BSI, Clostridium
difficile infection (CDI), ventilator-associated pneumonia (VAP), and urinary tract infection (UTI) served as
control variables that were not expected to be affected by CHG bathing.
Results: Bathing with CHG was associated with a statistically significant decrease in the rate of CVCassociated BSI (from 5.31 to 0.69 cases per 1,000 CVC-days; P = .006) and in the rate of blood culture
contamination (from 6.99 to 4.1 cases per 1,000 patient-days; P = .04). Rates of secondary BSI, CDI, VAP,
and UTI did not change significantly.
Conclusions: In our analysis of real-world practice, daily bathing of MICU patients with CHG was effective at
reducing rates of CVC-associated BSI and blood culture contamination. Controlled studies are needed to
determine whether these beneficial effects extend outside the MICU.
NosoBase n° 25680
Contrôle d'épidémies à Acinetobacter en réanimation
Rotimi VO; Jamal W; Salama M. Control of acinetobacter outbreaks in the intensive care unit. The Journal of
hospital infection 2009/11; 73(3): 286-287.
Mots-clés : SOIN INTENSIF; ACINETOBACTER; CONTROLE; EPIDEMIE
Staphylococcus aureus
NosoBase n° 25674
Connaissances du personnel de santé du Royaume-Uni des recommandations pour la pratique
concernant Staphylococcus aureus méticillino-résistant : étude par questionnaire
Brady R; MCDermott C; Cameron F; Graham C; Gibb AP. UK healthcare workers' knowledge of meticillinresistant Staphylococcus aureus practice guidelines; a questionnaire study. The Journal of hospital infection
2009/11; 73(3): 264-270.
Mots-clés :
PERSONNEL;
CONNAISSANCE;
STAPHYLOCOCCUS
AUREUS;
METICILLINORESISTANCE; RECOMMANDATION; QUESTIONNAIRE; MEDECIN; INFIRMIER
Effective infection control practice requires knowledge of and adherence to contemporary infection control
guidelines. Utilising a novel questionnaire tool, we evaluated knowledge of recently published guidelines on
meticillin-resistant Staphylococcus aureus (MRSA) precautions in a number of relevant healthcare worker
(HCW) populations. The questionnaire was developed from national UK MRSA practice guidelines and
consisted of 10 'true or false' statements. The questionnaire was utilised to assess knowledge in 293
participants from HCW and control populations. The participants included 188 doctors attending the British
Medical Association's Annual Representatives Meeting, 52 trainee surgeons attending the Association of
Surgeons in Training annual conference, 30 members of a non-clinical control population and 23 infection
control nurses (ICNs). The mean (SD) score for knowledge levels obtained from doctors was 6.6 (1.68), for
non-clinical control population was 4.7 (1.8) and for ICNs, 8.4 (1.12). There were significant differences in
knowledge levels between different population groups (P<0.001), UK employment region of the participant
(P=0.01) and the doctors' medical specialty (P=0.02). Career seniority and gender of the participant were not
significantly associated with differences in levels of knowledge. This questionnaire study evaluates a novel
discriminatory questionnaire tool which differentiates knowledge levels of MRSA practice guidelines among
a non-clinical population, HCWs and specialist infection control staff, thus providing a means for the rapid
assessment of MRSA educational interventions. We identify demographics within HCW target populations
which are associated with low levels of such knowledge. Consideration towards revising current HCW
educational programmes to improve knowledge and best practice in MRSA prevention is required.
NosoBase n° 25728
Epidémiologie des infections à Staphylococcus aureus résistant à la méticilline (SARM) en Amérique
Latine
Guzman-Blanco M; Mejia C; Isturiz R; Alvarez C; Bavestrello L; Gotuzzo E et al. Epidemiology of meticillinresistant Staphylococcus aureus (MRSA) in Latin America. International journal of antimicrobial agents
2009/10; 34(4): 304-308.
Mots-clés :
EPIDEMIOLOGIE;
STAPHYLOCOCCUS
AUREUS;
METICILLINO-RESISTANCE;
SURVEILLANCE
Meticillin-resistant Staphylococcus aureus (MRSA) has become a serious threat to public health worldwide.
Ongoing surveillance is essential to support infection control committees and clinicians in the prevention and
treatment of infection. However, in Latin America, resources for monitoring the changing epidemiology of
MRSA remain limited. In this article, we review the current situation of MRSA in Latin America in order to
highlight the need for a more harmonised effort to improve its management. Literature in the PubMed and
SciELO databases aswell as thewebsite of the Pan American Health Organization were searched for articles
and information about the epidemiology of MRSA in Latin America. MRSA is already the leading cause of
nosocomial infection in the Latin American region, and the number of reports of community-acquired MRSA
infections is also rising. However, the extent of the problem is not fully understood, especially since data
tend to come from large hospitals whereas much of the population is served by small community healthcare
centres that do not have extensive facilities for performing microbiological surveillance. In conclusion, widerreaching and co-ordinated programmes to provide regular MRSA surveillance reports are required across
the Latin American region.
NosoBase n° 25703
Candida albicans et Staphylococcus aureus forment des biofilms polymicrobiens : impacts sur la
résistance aux anti-infectieux
Harriott MM; Noverr MC. Candida albicans and Staphylococcus aureus form polymicrobial biofilms: effects
on antimicrobial resistance. Antimicrobial agents and chemotherapy 2009/09; 53(9): 3914-3922.
Mots-clés : STAPHYLOCOCCUS AUREUS; BIOFILM; CANDIDA ALBICANS; ANTIBIORESISTANCE;
SURFACE; ANTIFONGIQUE; RESISTANCE
Candida albicans readily forms biofilms on the surface on indwelling medical devices, and these biofilms
serve as a source of local and systemic infections. It is estimated that 27% of nosocomial C. albicans
bloodstream infections are polymicrobial, with Staphylococcus aureus as the third most common organism
isolated in conjunction with C. albicans. We tested whether S. aureus and C. albicans are able to form a
polymicrobial biofilm. Although S. aureus formed poor monoculture biofilms in serum, it formed a
substantial polymicrobial biofilm in the presence of C. albicans. In terms of architecture, S. aureus formed
microcolonies on the surface of the biofilm, with C. albicans serving as the underlying scaffolding. In
addition, S. aureus matrix staining revealed a different phenotype in polymicrobial versus monomicrobial
biofilms, suggesting that S. aureus may become coated in the matrix secreted by C. albicans. S. aureus
resistance to vancomycin was enhanced within the polymicrobial biofilm, required viable C. albicans, and
was in part mediated by C. albicans matrix. However, the growth or sensitivity to amphotericin B of C.
albicans is not altered in the polymicrobial biofilm.
NosoBase n° 25426
Epidémiologie des Staphylococcus aureus résistants à la méticilline dans une crèche de centre
hospitalier universitaire
Hewlett AL; Falk PS; Hughes KS; Mayhall CG. Epidemiology of methicillin-resistant Staphylococcus aureus
in a university medical center day care facility. Infection control and hospital epidemiology 2009/10; 30(10):
985-992.
Mots-clés : STAPHYLOCOCCUS AUREUS; METICILLINO-RESISTANCE; EPIDEMIOLOGIE; PEDIATRIE;
COLONISATION; PREVALENCE; TYPAGE; ANALYSE MULTIVARIEE
Objective: Few data are available on methicillin-resistant Staphylococcus aureus (MRSA) colonization in day
care. We performed a study in a medical university child care center to study the epidemiology of MRSA in
this population.
Design: Survey.
Setting: A child care center on the campus of a university medical center.
Methods: One hundred four children who attended the child care center and 32 employees gave samples
that were cultured for MRSA. Seventeen household members of the children and employee found to be
colonized with MRSA also gave samples that were cultured. Parents and employees completed
questionnaires about demographic characteristics, medical conditions and treatments, and possible
exposure risks outside the child care center. In addition, 195 environmental samples were taken from sites
at the childcare center. Isolates were analyzed for relatedness by use of molecular typing, and statistical
analysis was performed.
Results: The prevalence of MRSA in the children was 6.7%. One employee (3.1%) was colonized with
MRSA. Cultures of samples given by 6 of 17 (35.3%) family members of these children and the employee
yielded MRSA. MRSA was recovered from 4 of 195 environmental samples. Molecular typing revealed that
many of the MRSA isolates were indistinguishable, and 18 of the 21 isolates were community-associated
MRSA. Multivariable analysis revealed that receipt of macrolide antibiotics (P = .002; odds ratio, 39.6 [95%
confidence interval, 3.4-651.4]) and receipt of asthma medications (P = .024; odds ratio, 26.9 [95%
confidence interval, 1.5-500.7]) were related to MRSA colonization.
Conclusions: There was a low prevalence of MRSA colonization in children and employees in the child care
center but a higher prevalence of colonization in their families. Molecular typing showed that transmission of
MRSA likely occurred in the child care center. The use of macrolide antibiotics and asthma medications may
increase the risk of MRSA colonization in this population.
NosoBase n° 25616
Contrôle rapide d'une épidémie à Staphylococcus aureus méticillino-résistant (SARM) dans une
unité de réanimation médico-chirurgicale
Khan A; Lampitoc M; Salaripour M; Mckernan P; Devlin R; Muller MP. Rapid control of a methicillin resistant
Staphylococcus aureus (MRSA) outbreak in a medical surgical intensive care unit (ICU).
The Canadian journal of infection control 2009; 24(1): 12-16.
Mots-clés : STAPHYLOCOCCUS AUREUS; METICILLINO-RESISTANCE; SOIN INTENSIF; CONTROLE;
EPIDEMIOLOGIE; ENQUETE; EPIDEMIE
Background: Outbreaks of methicillin resistant Staphylococcus aureus in the intensive care unit setting
can be prolonged and difficult to control. This report describes the rapid control of an outbreak of methicillin
resistant Staphylococcus aureus in a 24-bed open-concept medical surgical intensive care unit with a
baseline methicillin resistant Staphylococcus aureus acquisition rate of 1.5 cases per 1000 patient days.
Interventions/Results: This institution's infection control policy mandates an outbreak investigation if two
cases of hospital-acquired methicillin resistant Staphylococcus aureus colonization or infection are identified
in an intensive care unit within a four-week period. In July 2007, methicillin resistant Staphylococcus aureus
was identified in the sputum of two patients within a one-week period. Screening of all patients in the
intensive care unit identified one additional case and a fourth case was identified from a clinical specimen
before control measures were implemented. Initial control measures included healthcare worker education,
enhanced surveillance, patient cohorting, and enhanced environmental cleaning. Despite these measures,
three more cases occurred. All patients were then placed in contact isolation, healthcare workers were
screened, and the nursing staff was cohorted. After two weeks without a case, two additional cases were
identified. Decolonization of all positive patients was initiated. No further cases occurred over a five-week
period and the outbreak was declared over. The outbreak resulted in nine cases of methicillin resistant
Staphylococcus aureus colonization (n = 8) or infection (n = 1) over an 11-week period. Only one of 175
healthcare workers was colonized and it was not the outbreak strain.
Conclusions: Early detection and the stepwise addition of infection control measures resulted in the rapid
control of an outbreak of methicillin resistant Staphylococcus aureus in a medical surgical intensive care unit
without unit closure. A low threshold of suspicion and the rapid initiation of unit wide surveillance were the
key steps in limiting the size of the outbreak. Complete cessation of transmission occurred after the initiation
of decolonization for all positive patients.
NosoBase n° 25675
Souffrance liée à Staphylococcus aureus résistant à la méticilline : expériences et compréhension
de la colonisation
Lindberg M; Carlsson M; Hogman M; Skytt B. Suffering from meticillin-resistant Staphylococcus aureus:
experiences and understandings of colonisation. The Journal of hospital infection 2009/11; 73(3): 271-277.
Mots-clés : STAPHYLOCOCCUS AUREUS; METICILLINO-RESISTANCE; COLONISATION; QUALITE;
PERSONNEL; PERCEPTION
The objective was to explore individuals' experiences and understandings of meticillin-resistant
Staphylococcus aureus (MRSA) colonisation. Thirteen interviews were performed and processed using
content analysis, resulting in the theme 'Invaded, insecure and alone'. The participants experienced fears
and limitations in everyday life and expressed a need to protect others from contagion. Moreover, they
experienced encounters with, and information from, healthcare workers differently: some were content,
whereas others were discontent. The described fears, limitations and inadequate professional-patient
relationship generated unacceptable distress for MRSA-colonised persons. Thus, the healthcare sector
should assume responsibility for managing MRSA, and healthcare workers must improve their
professionalism and information skills, so as to better meet MRSA-colonised persons' needs
NosoBase n° 25709
Surveillance moléculaire et analyse de la structure de la population de Staphylococcus aureus
méticillino-sensibles et méticillino-résistants dans des services à risque élevé
SergiI S; Donnarumma F; Mastromei G; Goti E; Nicoletti P; Pecile P et al. Molecular surveillance and
population structure analysis of methicillin-susceptible and methicillin-resistant Staphylococcus aureus in
high-risk wards. Journal of clinical microbiology 2009/10; 47(10): 3246-3254.
Mots-clés :
SURVEILLANCE;
BIOLOGIE
MOLECULAIRE;
STAPHYLOCOCCUS
AUREUS;
EPIDEMIOLOGIE; PCR; SOIN INTENSIF
In this study we report the results of analysis of 253 isolates of Staphylococcus aureus (132 methicillin
[meticillin]-resistant S. aureus [MRSA] isolates and 121 methicillin-susceptible S. aureus [MSSA] isolates)
from 209 patients admitted to 18 high-risk wards of six hospitals located in Florence, Italy, over an 8-month
period during which a program of epidemiological surveillance of hospital-acquired infections was
conducted. The majority (69%) of the 87 reported S. aureus infections were caused by MRSA. No outbreak
events have been reported. All the isolates were typed by amplified fragment length polymorphism (AFLP),
and AFLP profiles were analyzed in order to define similarity groups. The discriminatory power of AFLP is
very high with MSSA (Simpson index of diversity [D], 95.9%), whereas its resolution capability with MRSA
(D, 44.7%) is hampered by the well-known high clonality of these populations (the main MRSA group
accounted for 74% of the MRSA isolates). Combining AFLP, improved by visual inspection of
polymorphisms, with multiplex PCR greatly increases MRSA resolution (D, 85.5%), resolving the MRSA
population to a level that is one of the highest reported in the literature. Widespread and sporadic clones of
MSSA and MRSA were identified, and their diffusion in the different hospitals and wards over the
surveillance period was studied. The understanding of MSSA and MRSA population structures should be the
starting point for the design of a more rational surveillance program for S. aureus species, maximizing
benefits and reducing the cost of infection control strategies.
Surveillance
NosoBase n° 25427
Reproductibilité de l'effet de la surveillance pour diminuer les taux d'infections nosocomiales
Gastmeier P; Schwab F; Sohr D; Behnke M; Geffers C. Reproducibility of the surveillance effect to decrease
nosocomial infection rates. Infection control and hospital epidemiology 2009/10; 30(10): 993-999.
Mots-clés : SURVEILLANCE; TAUX; CATHETER VEINEUX CENTRAL; LABORATOIRE; BACTERIEMIE;
APPAREIL RESPIRATOIRE; VENTILATION; SITE OPERATOIRE; PROTHESE TOTALE DE GENOU;
CESARIENNE; VESICULE BILIAIRE; SOIN INTENSIF
Objective: To investigate whether the reduction effect due to participation in a nosocomial infection
surveillance system for laboratory-confirmed central venous catheter (CVC)-associated primary bloodstream
infection (BSI), ventilator-associated pneumonia (VAP), and surgical site infection (SSI) is reproducible for
different time periods, independent of confounding factors that might occur during a specific time period.
Methods: Data from the German national nosocomial infection surveillance system from the period January
1997 through June 2008 were used. CVC-associated BSI data and SSI data were analyzed for 3 starting
periods, and VAP data were analyzed for 2 starting periods. Monthly infection rates were calculated for the
following 36 months, and relative risks comparing the first and third surveillance years of each period were
calculated.
Results: A total of 2,399 CVC-associated BSI cases from 267 intensive care units, 3,637 VAP cases from
150 intensive care units, and 829 SSIs following 3 different procedures from 113 departments were
analyzed. A significant reduction in VAP was shown for both starting periods investigated (overall relative
risk [RR], 0.80 [95% CI, 0.74-0.86]). A significant reduction in CVC-associated BSI was demonstrated for 2
of 3 starting periods (overall RR, 0.83 [95% CI, 0.75-0.91]). A significant reduction in SSI was found for 2
starting periods for knee prosthesis insertion (overall RR, 0.56 [95% CI, 0.38-0.82]), for all of the 3 starting
periods for cesarean delivery (overall RR, 0.75 [95% CI, 0.61-0.93]), and for none of the 3 starting periods
for endoscopically performed cholecystectomy (overall RR, 0.89 [95% CI, 0.62-1.27]).
Conclusions: The surveillance effect, manifest as a significant reduction of nosocomial infection rates
between the first and third years of participation in a surveillance system, was observed independently from
the calendar year in which the surveillance activities started.
NosoBase n° 25671
Tendances régionales des infections à bactéries multi-résistantes aux antibiotiques dans des unités
de réanimation en Allemagne : modèle en temps réel pour surveillance épidémiologique et analyse
Kohlenberg A; Schwab F; Meyer E; Behnke M; Geffers C; Gastmeier P. Regional trends in multidrugresistant infections in German intensive care units: a teal-time model for epidemiological monitoring and
analysis. The Journal of hospital infection 2009/11; 73(3): 239-245.
Mots-clés : SOIN INTENSIF; EPIDEMIOLOGIE; MULTIRESISTANCE; SURVEILLANCE; ANALYSE;
RESEAU;
STAPHYLOCOCCUS
AUREUS;
METICILLINO-RESISTANCE;
ENTEROCOCCUS;
VANCOMYCINE; ESCHERICHIA COLI; KLEBSIELLA PNEUMONIAE; BETA-LACTAMASE A
SPECTRE ELARGI; INCIDENCE; INFORMATIQUE
A new surveillance module for multidrug-resistant (MDR) bacteria was added to the intensive care
component of the German Nosocomial Infection Surveillance System. Participating intensive care units
(ICUs) report data on all patients colonised or infected with meticillin-resistant Staphylococcus aureus
(MRSA), vancomycin-resistant enterococci (VRE) and extended-spectrum beta-lactamase-producing
Escherichia coli and Klebsiella pneumoniae (ESBL-EC/KP). To determine the regional distribution of MRSA,
VRE and ESBL-EC/KP in Germany, incidence densities (IDs) of these bacteria per 1000 patient-days were
calculated for each ICU and pooled for ICUs of five German regions for the years 2005 and 2006. A total of
176 ICUs including 284 142 patients and 1 021 579 patient-days reported data concerning 5490 cases of
MDR bacteria. The pooled IDs were 4.54, 0.54 and 0.29 cases per 1000 patient-days for MRSA, ESBLEC/KP and VRE cases and 1.56, 0.32 and 0.13 per 1000 patient-days for MRSA, ESBL-EC/KP and VRE
infections, respectively. While there were no significant differences in the incidence densities of MRSA
infections between regions, the IDs of VRE and ESBL-EC/KP infections showed significant regional
variation. The regions also differed in the proportion of ICUs per region that reported at least one infection
with MRSA, ESBL-EC/KP or VRE in 2005-2006 and these differences ranged from 82% to 91% for MRSA,
from 34% to 76% for ESBL-EC/KP and from 8% to 42% for VRE. This new surveillance module enables
ICUs to monitor the occurrence of MDR bacteria by comparing local incidence densities with a national
reference and shows significant regional variation of MDR bacteria in Germany.