To assess the impact of isolation precautions on the incidence of patients colonized or infected with Acinetobacter baumannii (case patients) in a university hospital during the period from 1999 to 2006.

Ecological study.

The Besançon University Hospital in France, a 1,200-bed acute care hospital with approximately 50,000 admissions per year.

Using Poisson regression analysis, we evaluated a total of 350,000 patient-days to determine the annual incidence of case patients. This annual incidence was used as the outcome variable, and infection control practices, antibiotic use, and other aggregated data regarding patients' age, sex, McCabe score, and immune status were used as covariates.

The implementation of isolation precautions was independently and negatively associated with the incidence of patients colonized or infected with A. baumannii (relative risk, 0.50 [95% confidence interval, 0.40–0.64]; P < .001).

Our study suggests that the implementation of isolation precautions, in addition to standard precautions, effectively prevents the spread of A. baumannii in a hospital setting.

To evaluate the usefulness of screening cultures in the control of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in intensive care units (ICUs).

A 4-year retrospective study.

Two adult ICUs of a university-affiliated public hospital in France.

A total of 7,777 specimens were analyzed and 28 (0.97%) of 2,883 screened patients had a positive result on a screening test, among the 3,678 admitted patients. Thirteen of these 28 patients were only carriers; 4 were carriers and then were colonized or infected 2, 2, 3, and 8 days later, respectively; and 11 were colonized or infected before a screening test was positive. Cluster analysis showed that the occurrence of ESBL-producing Enterobacteriaceae cross-transmission within both ICUs was limited to 9 cases. Thus, most cases (19 of 28) were probably imported. Surveillance cultures failed to detect 9 of the 19 cases.

The low prevalence of ESBL-producing Enterobacteriaceae carriers on admission (0.45%) and the relative ineffectiveness of our screening test to detect imported cases suggest that systematic detection of ESBL-producing Enterobacteriaceae in ICU patients is not cost-effective and that the use of clinical cultures may be sufficient to control ESBL-producing Enterobacteriaceae in non-epidemic situations.

To describe Burkholderia cepacia contamination of a cornea bank and the measures taken to identify and eliminate the source of infection.

Cultures were performed to assess the extent and source of contamination, and pulsed-fleld gel electrophoresis was used for molecular typing.

Routine surveillance cultures identified 5 contaminated corneas during a 10-day period. Additional cultures showed that 28 of 88 samples were positive for this organism. Environmental investigation showed that an open bottle of trypan blue used to assess corneal morphology was contaminated with the epidemic strain.

Trypan blue played a major role in this contamination of corneas. This episode shows that microbial contamination can affect transplanted corneas despite ongoing culture surveillance and suggests that new methods may be needed to avoid this risk.

To evaluate the contribution of screening to the detection of cases of methicillin-resistant Staphylococcus aureus (MRSA) in a chronic-care facility.

Surveillance and laboratory observational study.

During a 7-month period, we compared imported and acquired MRSA in a chronic-care center by screening patients for carriage of MRSA on admission and discharge, and by recording all cases of clinical specimens positive for MRSA

The study was conducted in a 120-bed chronic-care center. This center admits approximately 850 patients per year. Approximately 90% of the patients were elderly and were admitted from other hospitals.

Of 519 patients admitted during the study period, 129 were positive for MRSA at some point during their residence, including 60 (11.6%) with MRSA found within 48 hours of admission and 69 (13.3%; 53% of all positives) with nosocomial MRSA Of the 519 admissions, 332 (64%) were discharged, of whom 62 (19%) were positive for MRSA. Of these 62, 43 (69%) acquired their MRSA during their stay in the center.

Our study confirms the amplification effect of chronic-care facilities on MRSA propagation. It also shows that screening for MRSA carriage in a chronic-care center facilitates the early identification of a large proportion of patients with MRSA.

To determine the rates and routes of Acinetobacter baumanii colonization and pneumonia among ventilated patients in a surgical intensive-care unit (SICU) before and after architectural modifications.

A nonsequential study comparing two groups of patients. All isolates from systematic and clinical samples were genotyped by pulsed-field gel electrophoresis (PFGE). Records of patients hospitalized during the first and second periods were reviewed and findings were compared. Between the two periods, the SICU was remodeled from enclosed isolation rooms and open rooms to only enclosed isolation rooms with handwashing facilities in each room.

All patients hospitalized and mechanically ventilated for more than 48 hours in the 15-bed SICU of the University Hospital of Besançon (France).

For the first and second periods, the rates of colonization were, respectively, 28.1% and 5.0% of patients (P<10−7; relative risk [RR], 2.23; 95% confidence interval [CI95], 1.8-2.75) and the specific rates of bronchopulmonary (BP) colonization were, respectively, 9.1 and 0.5 per 1,000 days of mechanical ventilation (P<10−5). Seven major PFGE isolate types were identified, 4 of which were isolated from 44 of the 47 colonized or infected patients. Logistic regression analysis showed that colonization was not associated with patient characteristics.

Conversion from open rooms to isolation rooms may help control nosocomial BP tract acquisition of A baumanii in mechanically ventilated patients hospitalized in an SICU.