Molecular epidemiologic surveillance of Acinetobacter baumannii by polymerase chain reaction-randomly amplified polymorphic DNA analysis in a university hospital for 3 consecutive study periods.

Twelve different Acinetobacter baumannii genotypes (A-L) were detected. Although only 2 genotypes were detected during the first period and genotype A appeared to be the most common genotype, genotype D was included in these genotypes during the second study period. Genotype A completely disappeared during the third period. Although the presence of genotype C and the genotype D continued during the third period, 9 new genotypes were detected during this period. Genotype A appeared to be the most common genotype in the hospital (detected in 19 different clinics). The distribution of genotypes in clinical samples correlated with patient traffic between them. Some genotypes were found in both clinical and environmental samples. Seventeen different antibiotypes were detected, according to antibiotic susceptibility profiles.

Environmental contamination, airborne transmission, patient transfer, and cross-contamination play important roles in epidemics caused by A. baumannii in our hospital. The distribution of genotypes can change over time, so antibiotyping is not appropriate for the epidemiological analysis of A. baumanii infection.

Recognizing that the potential transmission of influenza virus would be concentrated at a hospital's primary point of entry, we determined rates of staff compliance with the influenza vaccination recommendations of the Advisory Committee on Immunization Practices (ACIP) in the Emergency Department (ED). We describe the basic knowledge concerning influenza transmission and factors influencing vaccination decisions among ED staff.

Cross-sectional study.

A large urban teaching hospital. Participants included ED staff, visiting professionals from other departments, and emergency medical service personnel transferring patients to the hospital.

Of 230 surveys that were distributed, 200 were completed. One hundred one respondents (51%) were female. The overall influenza vaccination rate was 50%. Having had influenza previously was the most instrumental factor in whether or not a respondent chose vaccination (P<.001). Use of the Employees Health Services Free Vaccine Program (FVP) was a very important factor influencing whether ED staff sought influenza vaccination (P<.0001). Prior knowledge of the ACIP recommendations proved to be not statistically important (P = .03). A significant factor for respondents declining vaccination was the concern that illness could be caused by the vaccine (P<.0001). Variables such as sex of the respondents (P = .6714) and type of job (P = .3628) were not associated with vaccination.

Despite ACIP recommendations, 50% of respondents did not receive an influenza vaccination. Misconceptions regarding influenza vaccine efficacy, concerns about adverse effects, and fear of contracting illness were significantly associated with noncompliance with vaccination. Variables that were important contributors to compliance with vaccination were prior influenza illness and services rendered by the FVP.

Clinical practice guidelines and recommended practices to control use of antibiotics have been published, but the effect of these practices on antimicrobial resistance (AMR) rates in hospitals is unknown. The objective of this study was to examine relationships between antimicrobial use control strategies and AMR rates in a national sample of US hospitals.

Cross-sectional, stratified study of a nationally representative sample of US hospitals.

A survey instrument was sent to the person responsible for infection control at a sample of 670 US hospitals. The outcome was current prevalences of 4 epidemiologically important, drug-resistant pathogens, considered concurrently: methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci, ceftazidime-resistant Klebsiella species, and quinolone (ciprofloxacin)-resistant Escherichia coli Five independent variables regarding hospital practices were selected from the survey: the extent to which hospitals (1) implement practices recommended in clinical practice guidelines and ensure best practices for antimicrobial use, (2) disseminate information on clinical practice guidelines for antimicrobial use, (3) use antimicrobial-related information technology, (4) use decision support tools, and (5) communicate to prescribers about antimicrobial use. Control variables included the hospitals' number of beds, teaching status, Veterans Affairs status, geographic region, and number of long-term care beds; and the presence of an intensive care unit, a burn unit, or transplant services. A generalized estimating equation modeled all resistance rates simultaneously to identify overall predictors of AMR levels at the facility.

Completed survey instruments were returned by 448 hospitals (67%). Four antimicrobial control measures were associated with higher prevalence of AMR. Implementation of recommended practices for antimicrobial use (P< .01) and optimization of the duration of empirical antibiotic prophylaxis (P<.01) were associated with a lower prevalence of AMR. Use of restrictive formularies (P = .05) and dissemination of clinical practice guideline information (P<.01) were associated with higher prevalence of AMR. Number of beds and Veterans Affairs status were also associated with higher AMR rates overall.

Implementation of guideline-recommended practices to control antimicrobial use and optimize the duration of empirical therapy appears to help control AMR rates in US hospitals. A longitudinal study would confirm the results of this cross-sectional study. These results highlight the need for systems interventions and reengineering to ensure more-consistent application of guideline-recommended measures for antimicrobial use.

To examine whether intervention by infectious diseases physicians (IDPs) in the treatment decisions that emphasize adequate antifungal treatment and early removal of central venous catheter for patients with Candida bloodstream infection (BSI) improves prognosis.

Retrospective cohort study of patients with Candida BSI, comparing the prognosis of patients before and after the start of the intervention.

A 1,240-bed, tertiary care university hospital.

Forty patients with Candida BSI during a 2-year period, from January 2001 to December 2002, were included in the study Twenty-three patients in the first year after the start of intervention by IDPs (intervention group) were compared with 17 patients in the first year before the start of the IDP intervention (baseline group).

In January 2002, a total of 5 IDPs at Kyoto University Hospital gave unsolicited recommendations on antifungal treatment and advised all physicians treating inpatients who had Candida BSI to remove the central venous catheter.

No significant difference was seen between the 2 groups in patients' clinical background, species, and fluconazole susceptibility of the causative organisms. The 30-day survival rate was significantly better in the intervention group (18 [78%] of 23 patients) than in the baseline group (7 [44%] of 16 patients; P = .04 by Fisher's exact test). More patients in the intervention group than in the baseline group received appropriate antifungal therapy (81% vs 50%) and had their central venous catheter removed at an appropriate time (95% vs 81%)

The introduction of an active system of IDP consultation for every case of Candida BSI in our hospital substantially improved patient outcomes.

To evaluate the economic and clinical impact of infection with extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella species (ESBL-EK).

A matched-cohort analysis of the cost of illness.

An 810-bed, urban, community hospital in Hartford, Connecticut.

Twenty-one case patients infected with ESBL-EK at a site other than the urinary tract were matched with 21 control subjects infected with a non–ESBL-producing organism on the basis of pathogen species, age, anatomic site of infection, hospitalization in the intensive care unit (ICU) during the time of infection, date of hospitalization, and initial antibiotics received.

Mean infection-related costs per patient were significantly greater for case patients than for control patients ($41,353 vs $24,902; P = .034). Infection-related length of stay was the main driver of cost, which was prolonged for case patients, compared with control patients (21 vs 11 days; mean difference, 9.7 days [95% confidence interval {CI}, 3.2-14.6 days] P = .006). The additional cost attributed to the presence of an ESBL-EK infection was $16,450 per patient (95% CI, $965-$31,937). Case patients were more likely than control patients to have clinical failure (P = .027), and the rate of treatment success for case patients whose initial treatment involved antibiotics other than carbapenems was lower than that for their matched control patients (39% vs 83%; P = .013). Treatment was successful in patients for whom initial treatment was with a carbapenem, regardless of the ESBL status of the pathogen.

The cost of non–urinary tract infections caused by ESBL-EK was 1.7 times the cost of non–urinary tract infections caused by non-ESBL producers. Prompt recognition and appropriate antimicrobial selection may minimize this ESBL-related impact on hospital costs.

To investigate whether carriage of multidrug-resistant bacteria is a risk factor for nosocomial infection and whether detection of carriage is predictive of subsequent onset of nosocomial infection.

In this observational cohort (study period, June 1998 through October 2002), nasal and rectal swab specimens from 412 consecutive patients admitted to the intensive care unit were tested for carriage of multidrug-resistant bacteria. Concomitantly, the bacteria responsible for any subsequent nosocomial infection, the date of infection, and some of the known clinical risk factors for nosocomial infection were noted. These factors were adjusted for potential confounders, using a Cox model stratified on the propensity score of multidrug-resistant bacteria carriage. The diagnostic characteristics of a carriage test, including the positive and negative diagnostic likelihood ratios, were calculated for all strata of the propensity score.

Forty-two patients were carrying multidrug-resistant bacteria. Nosocomial infection occurred in 95 patients, of whom 16 (38%) were carriers, and 79 (83%) were noncarriers (P = .01). After adjustment for potential confounders, statistical analysis revealed that carriage remained a risk factor for nosocomial infection (relative risk, 2.08 [95% confidence interval {CI}, 1.13-3.81]). Receipt of antibiotic treatment at the time of intensive care unit admission was found to be protective against nosocomial infection. A positive result of test for detection of carriage seemed to be an efficient predictor of subsequent nosocomial infection (positive diagnostic likelihood ratio, 2.05 [95% CI, 1.15-3.66]), although a negative test result was not a predictor of subsequent nosocomial infection (negative likelihood ratio, 0.91 [95% CI, 0.73-1.11]).

Carriage proved to be a risk factor for subsequent nosocomial infection. However, the carriage test was useful as a predictive tool only for patients with a positive test result.

To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF).

Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts.

A 104-bed community LTCF between March 1 and April 7, 2004.

A cohort of LTCF residents with assigned beds at the time of the outbreak.

Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers.

Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors.

Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs.

To identify differences between unit-specific and hospital-wide antibiograms and to determine the potential impact of these differences on selection of empirical antimicrobial therapy.

A 625-bed tertiary care medical center.

Antimicrobial susceptibility results were collected for all inpatient clinical bacterial isolates recovered over a 3-year period; isolates were categorized by the hospital location of the patient at the time of sampling and by the anatomic site from which the isolate was recovered. Antibiograms from each unit were compiled for the most commonly isolated organisms and were compared to the hospital-wide antibiogram.

A total of 9,970 bacterial isolates were evaluated in this study, including 2,646 enterococcal isolates, 2,806 S. aureus isolates, 2,795 E. coli isolates, and 1,723 Pseudomonas aeruginosa isolates. The percentages of bacterial isolates resistant to antimicrobials were significantly higher in the medical ICU and surgical ICU than the hospital-wide antibiogram would have predicted, whereas the percentages of isolates susceptible to antimicrobials were significantly higher in the non-ICU units, compared with the hospital overall. However, on general medicine units, the prevalence of susceptibility to levofloxacin was significantly lower than that for the hospital overall.

Unit-specific antibiograms are important for making informed decisions about empirical antimicrobial therapy, because the hospital-wide antibiogram may mask important differences in susceptibility rates across different units. These differences may have important implications for selecting the optimal empirical antimicrobial therapy.

To compare the incidence rates of catheter-related bloodstream infection associated with different vascular access methods in patients receiving hemodialysis.

Tertiary care public hospital in Western Australia.

Retrospective analysis of surveillance data collected by the hospital's infection control department.

The number of confirmed bloodstream infections for each type of vascular access was identified for the period from July 2002 through June 2003. The corresponding number of patient-days was determined to calculate the infection incidence rates. The serially correlated data were then analyzed using Poisson generalized estimating equations.

A total of 32 confirmed bloodstream infections were identified. Infection rates, in number of infections per 1,000 patient-days, were as follows: 0.4 for native arteriovenous fistulae; 2.86 for synthetic arteriovenous grafts; 4.02 for permanent, tunneled, cuffed central venous catheters; and 20.2 for temporary, nontunneled, noncuffed central venous catheters. Compared with permanent catheters, the monthly infection rate associated with the temporary catheters was significantly higher (incident rate ratio [IRR], 5.025 [95% confidence interval {CI}, 1.532-16.484]; P = .008) and that of arteriovenous fistulae was significantly lower (IRR, 0.099 [95% CI, 0.030-0.324]; P = .001). The monthly infection rate for arteriovenous grafts was not significantly different from that for permanent central venous catheters (IRR, 0.702 [95% CI, 0.246-2.008]; P = .510).

A hierarchy of infection risk associated with vascular access type is evident. Native arteriovenous fistulae should be recommended for all patients receiving chronic hemodialysis, to minimize infection.