To evaluate nosocomial infection (NI) surveillance strategies in French ICUs and to identify similar patterns defining subsets within which comparisons can be made.

A questionnaire was sent to all French ICUs, and a random sample of nonresponders was interviewed.

Three hundred ninety-five responder ICUs (69%) in France.

In 282 ICUs (71%), a dedicated ICU staff member was responsible for infection control activities. The microbiology laboratory was usually in the hospital (90%) and computerized (94%) but issued regular hospital microbiology records in only 48% of cases. Patients receiving mechanical ventilation, central venous catheterization, and urinary catheterization were 90%, 79%, and 60%, respectively. Patients were screened for carriage of mul-tidrug-resistant bacteria on admission and during the stay in 70% and 60% of ICUs, respectively, most often targeting MRSA. Quantitative cultures were used to diagnose ventilator-associated pneumonia (VAP) in 90% of ICUs, including distal specimens in 80% and bronchoscopy specimens in 60%. Quantitative central venous catheter (CVC)-segment cultures were used in 70% of ICUs. All CVCs were cultured routinely in 53% of the ICUs. Despite wide variations in infection control and surveillance strategies, multiple correspondence analysis identified 13 key points (4 structural variables and 9 variables concerning the diagnosis of VAP, the surveillance and diagnosis of catheter-related and urinary tract infections, and the mode of screening of MRSA carriers) that categorize the variability of French ICUs' approaches to NIs.

This study revealed profound differences in N1 surveillance strategies across ICUs, indicating a need for caution when using N1 surveillance data for comparisons and benchmarking.

To examine the extent to which the strategies recommended by the National Foundation for Infectious Diseases (NFID)-Centers for Disease Control and Prevention (CDC) co-sponsored workshop, Antimicrobial Resistance in Hospitals: Strategies to Improve Antimicrobial Use and Prevent Nosocomial Transmission of Antimicrobial-Resistant Microorganisms, have been implemented and the relationship between the degree of implementation and hospital culture, leadership, and organizational factors.

Survey.

A representative sample of U.S. hospitals stratified by teaching status, bed size, and geographic region.

Infection control professionals.

Surveyed hospitals had implemented strategies to optimize the use of antimicrobials and to detect, report, and prevent transmission of antimicrobial-resistant microorganisms. Multivariate analyses found that hospitals with a greater degree of implementation of the NFID–CDC strategic goals were more likely to have management support, education of staff, and interdisciplinary groups specifically to address these issues; they were also more likely to engage in benchmarking on broader quality of care indicators.

Most surveyed hospitals had implemented some measures to address the NFID–CDC recommendations; however, hospitals need to do much more to improve antimicrobial use and to increase their efforts to detect, report, and control the spread of antimicrobial resistance. A supportive hospital administration must foster a culture of ongoing support, education, and interdisciplinary work groups focused on this important issue to successfully accomplish these goals.

Antimicrobial resistance is a growing clinical and public health crisis. Experts have recommended measures to monitor antimicrobial resistance; however, little is known regarding their use.

We describe the use of procedures to detect and report antimicrobial resistance in U.S. hospitals and the organizational and epidemiologic factors associated with their use.

In 2001, we surveyed laboratory directors (n = 108) from a random national sample of hospitals. We studied five procedures to monitor antimicrobial resistance: (1) disseminating antibiograms to physicians at least annually, (2) notifying physicians of antimicrobial-resistant infections, (3) reporting susceptibility results within 24 hours, (4) using automated testing procedures, and (5) offering molecular typing. Explanatory variables included organizational characteristics and patterns of antimicrobial resistance for oxacillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, quinolone-resistant Escherichia coli, and extended-spectrum beta-lactamase-producing Klebsiella species. Generalized estimating equations accounting for the correlation among outcomes at the facility level were used to identify predictors of the five outcomes.

Use of the procedures ranged from 85% (automated testing) to 33% (offering molecular typing) and was related to teaching hospital status (OR, 3.1; CI95, 1.5–6.5), participation of laboratory directors on the infection control committee (OR, 1.7; CI95, 1.1–2.8), and having at least one antimicrobial-resistant pathogen with a prevalence greater than 10% (OR, 2.2; CI95, 1.4–3.3).

U.S. hospitals underutilize procedures to monitor the spread of antimicrobial resistance. Use of these procedures varies and is related to organizational and epidemiologic factors. Further efforts are needed to increase their use by hospitals.

To evaluate the cost-effectiveness and detection sensitivity associated with three active surveillance strategies for the identification of patients harboring vancomycin-resistant enterococci (VRE) to determine which is the most medically and economically useful.

Culture for VRE from 200 consecutive stool specimens submitted for Clostridium difficile culture. Following this, risk factors were assessed for patients whose culture yielded VRE, and a cost-effectiveness evaluation was performed using a decision analytic model with a probabilistic analysis.

A 688-bed, tertiary-care facility in Chicago, Illinois, with approximately 39,000 annual admissions, 7,000 newborn deliveries, 56,000 emergency department visits, and 115,000 home care and 265,000 outpatient visits.

All stool specimens submitted to the clinical microbiology laboratory for C. difficile culture from hospital inpatients.

From 200 stool samples submitted for C. difficile testing, we identified 5 patients with VRE in non-high-risk areas not screened as part of our routine patient surveillance. Medical record review revealed that all 5 had been hospitalized within the prior 2 years. Three of 5 had a history of renal impairment. The strategy that would involve screening the greatest number of patients (all those with a history of hospital admission in the prior 2 years) resulted in highest screening cost per patient admitted ($2.48), lower per patient admission costs ($480), and the best survival rates.

An expanded VRE surveillance program that encompassed all patients hospitalized within the prior 2 years was a cost-effective screening strategy compared with a more traditional one focused on high-risk units.

To characterize vancomycin use at a pediatric tertiary-care hospital, to discriminate between initial (≤ 72 hours) and prolonged (> 72 hours) inappropriate use, and to define patient characteristics associated with inappropriate use.

Vancomycin courses were retrospectively reviewed using an algorithm modeled on HICPAC guidelines. Data were collected regarding patient demographics, comorbidities, other medication use, and nosocomial infections. The association between each variable and the outcome of inappropriate use was determined by longitudinal regression analysis. A multi-variable model was constructed to assess risk factors for inappropriate initial and prolonged vancomycin use.

A pediatric tertiary-care medical center.

Children older than 1 year who received intravenous vancomycin from November 2000 to June 2001.

Three hundred twenty-seven vancomycin courses administered to 260 patients were evaluated for appropriateness. Of initial courses, 114 (35%) were considered inappropriate. Of 143 prolonged courses, 103 (72%) were considered inappropriate. Multivariable risk factor analysis identified the following variables as significantly associated with inappropriate initial use: admission to the surgery service, having a malignancy, receipt of a stem cell transplant, and having received a prior inappropriate course of vancomycin. No variables were identified as significant risk factors for inappropriate prolonged use.

Substantial inappropriate use of vancomycin was identified. Prolonged inappropriate use was a particular problem. This risk factor analysis suggests that interventions targeting patients admitted to certain services or receiving multiple courses of vancomycin could reduce inappropriate use.

Antibiotic resistance in the long-term-care facility (LTCF) setting is of increasing concern due to both the increased morbidity and mortality related to infections in this debilitated population and the potential for transfer of resistant organisms to other healthcare settings. Longitudinal trends in antibiotic resistance in LTCFs have not been well described.

Correlational longitudinal survey study.

Four LTCFs in Pennsylvania.

All clinical cultures of residents of the participating LTCFs (700 total beds) from 1998 through 2003. We assessed the annual prevalence of resistance to various antimicrobials of interest for the following organisms: Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and enterococcus species.

A total of 4,954 clinical isolates were obtained during the study. A high prevalence of antimicrobial resistance was noted for many organism-drug combinations. This was especially true for fluoroquinolone susceptibility among the Enterobacteriaceae (susceptibility range, 51.3% to 92.2%). In addition, the prevalence of resistance to various agents differed significantly across study sites. Finally, significant increasing trends in resistance were noted over time and were most pronounced for fluoroquinolone susceptibility among the Enterobacteriaceae.

The prevalence of antimicrobial resistance has increased significantly in LTCFs, although trends have varied substantially across different institutions. These trends have been particularly pronounced for fluoroquinolone resistance among the Enterobacteriaceae. These findings demonstrate that antimicrobial resistance is widespread and increasing in LTCFs, highlighting the need for future studies to more clearly elucidate the risk factors for, and potential interventions against, emerging resistance in these settings.

To determine risk factors for ceftazidime-resistant Klebsiella pneumoniae infection and the effect of cef-tazidime-resistant K. pneumoniae infection on mortality during an isolated outbreak.

Case–control investigation using clinical and molecular epidemiology and prospective analysis of infection control interventions.

Surgical intensive care unit of a university-affiliated community hospital.

Fourteen case-patients infected with ceftazidime-resistant K. pneumoniae and 14 control-patients.

Ten of 14 case-patients had identical strains by pulsed-field gel electrophoresis. Broad-spectrum antibiotic therapy before admission to the unit was strongly predictive of subsequent ceftazidime-resistant K. pneumoniae infection. In addition, patients with ceftazidime-resistant K. pneumoniae infection experienced increased mortality (odds ratio, 3.77).

Cephalosporin restriction has been shown to decrease the incidence of nosocomial ceftazidime-resistant K. pneumoniae. However, isolated clonal outbreaks may occur due to lapses in infection control practices. Reinstatement of strict handwashing, thorough environmental cleaning, and repeat education led to termination of the outbreak. A distinct correlation between ceftazidime-resistant K. pneumoniae infection and mortality supports the important influence of antibiotic resistance on the outcome of serious bacterial infections.

Acinetobacter baumannii has emerged as an opportunistic pathogen among acutely ill patients, especially those with thermal injury. A prospective 8-month study was conducted to describe the clinical and molecular epidemiology of multidrug-resistant A. baumannii affecting a single hospital.

Univariate analysis comparing Smal macrorestriction patterns of A. baumannii generated by pulsed-field gel electrophoresis (PFGE) versus clinical and demographic risk factors.

A total of 200 isolates from 76 patients were collected, of which 185 isolates from 76 patients were analyzed by PFGE. A total of 17 distinct PFGE clonal types were identified. One clonal type (strain A) represented 129 isolates from 49 patients. A group of related clonal types (strain A variants) were identified as 40 isolates from 20 patients. The only risk factor other than geographic location associated with the presence of strain A was prior treatment with antibiotics active against gram-negative bacteria (P = .0015). The two clonal types differed in antibiotic resistance profiles: 25% of strain A isolates, the dominant strain in the burn unit, were susceptible to at least one antibiotic tested. In contrast, approximately 80% of the other strain types were susceptible to at least one antibiotic and were cultured from patients admitted elsewhere in the hospital. No combination of antibiotics was observed to yield additive or synergistic activity.

Clonally related strains of Acinetobacter that differ in susceptibility patterns may coexist within a single hospital, dependent on the selective pressure related to antibiotic exposure.

To detect putative clonal dissemination of multidrug-resistant, coagulase-negative staphylococci (CNS) in a university hospital in northern Sweden.

All consecutive routine clinical samples from our hospital were screened during two periods (November and December 2001 and September and October 2002) for the presence of multidrug-resistant (defined as resistant to oxacillin, clindamycin, co-trimoxazole, gentamicin, and fusidic acid, but susceptible to vancomycin) isolates of CNS. Genetic similarity between isolates was analyzed using pulsed-field gel electrophoresis (PFGE) and a computer program.

Seventy multidrug-resistant isolates from 62 patients were identified, 28 during the 2001 period and 42 during the 2002 period. All isolates except one, which was Staphylococcus haemolyticus, were identified as S. epidermidis. Multidrug-resistant CNS were isolated in samples obtained from 24 different wards. Two subgroups (group A and group B) of S. epidermidis that differed by approximately 40% in PFGE band similarity were identified. Group A consisted of 44 isolates with a PFGE band similarity of greater than 70% that included 6 subgroups consisting of 3 to 16 isolates that expressed a 100% similarity. These isolates were identified during both sampling periods in cultures performed in 18 different wards. A clonal origin could not be excluded for some of the remaining 26 isolates belonging to group B, but none had identical PFGE patterns, suggesting a more diverse origin.

The results of this study suggest clonal spread of multidrug-resistant CNS within our hospital and that some clones are endemic in the hospital environment.

To assess the feasibility of a quarterly antibiotic cycling program at two community hospitals and to evaluate its safety and impact on antibiotic use, expenditures, and resistance.

Nonrandomized, longitudinal cohort study.

Two community hospitals, one teaching and one non-teaching.

Adult medical and surgical inpatients requiring empiric antibiotic therapy.

We developed and implemented a treatment protocol for the empiric therapy of common infections. Between July 2000 and June 2002, antibiotics were cycled quarterly; quinolones, beta-lactam–inhibitor combinations, and cephalosporins were used. Protocol adherence, adverse drug events, nosocomial infections, antibiotic use and expenditures, resistance among clinical isolates, and length of stay were assessed during eight quarters.

Physicians adhered to the protocol for more than 96% of 2,494 eligible patients. No increases in nosocomial infections or adverse drug events were attributed to the cycling protocol. Antibiotic acquisition costs increased 31%; there was a 14.7% increase in antibiotic use. Length of stay declined by 1 day. Quarterly variability in the prevalence of vancomycin-resistant enterococci and ceftazidime resistance among combined gram-negative organisms were noted.

Implementation of an antibiotic cycling program is feasible in a community hospital setting. No adverse safety concerns were identified. Antibiotic cycling was more expensive, partly due to an increase in antibiotic use to optimize initial empiric therapy. Quarterly antibiogram patterns suggested that antibiotic cycling may have impacted resistance, although the small number of isolates precluded statistical analysis. Further assessment of this approach is necessary to determine its relationship to antimicrobial resistance.

To evaluate the clinical features of ciprofloxacin-resistant Enterobacter bacteremia and to examine the risk factors for ciprofloxacin resistance in Enterobacter species isolates causing bacteremia.

A case-control study.

A 1,500-bed, tertiary-care university hospital and referral center.

All patients older than 16 years with Enterobacter species isolated from blood were enrolled. The medical records of 183 patients with clinically significant Enterobacter bacteremia from January 1998 to December 2002 were identified. We compared patients with bacteremia caused by ciprofloxacin-susceptible isolates with patients with bacteremia caused by ciprofloxacin-resistant isolates.

Twenty-three (12.6%) of the patients had bacteremia caused by isolates resistant to ciprofloxacin. There were no significant differences in age, gender, underlying diseases, primary site of infection, or Acute Physiology and Chronic Health Evaluation II score between the ciprofloxacin-resistant and the ciprofloxacin-susceptible groups. Broad-spectrum cephalosporin resistance, defined as resistance to cefotaxime or ceftazidime in vitro, was detected in 21 (91.3%) of 23 ciprofloxacin-resistant isolates compared with 65 (40.6%) of 160 ciprofloxacin-susceptible isolates (P < .001). Multivariate analysis revealed that independent risk factors for ciprofloxacin resistance were the prior receipt of fluoroquinolones (P < .001) and broad-spectrum cephalosporin resistance (P < .001).

In Enterobacter species isolates causing bacteremia, ciprofloxacin resistance was closely associated with the prior receipt of fluoroquinolones and broad-spectrum cephalosporin resistance. The close relationship between ciprofloxacin resistance and broad-spectrum cephalosporin resistance is particularly troublesome because it severely restricts the therapeutic options for Enterobacter species infection.

The characteristics of fluoroquinolone use that increase the risk of selecting for fluoroquinolone resistance remain unclear. Exposure to subtherapeutic levels of fluoroquinolone promotes bacterial development of fluoroquinolone resistance. Oral fluoroquinolone absorption is significantly impaired by coadministration with many common di- or tri-valent cation-containing compounds (DTCCs), and this interaction has been associated with therapeutic failure. However, the prevalence of, and risk factors for, in-hospital coadministration of oral fluoroquinolones with DTCCs is unknown.

Case-control study.

A 625-bed, tertiary-care medical center.

All inpatients who were dispensed oral levofloxacin from July 1, 1999, to June 30, 2001, were included. Coadministration was defined by documented administration of any DTCC within 2 hours of levofloxacin. Complete coadministration was defined as coadministration complicating every dose of a course of levofloxacin.

A subset of 3,227 (41.0%) of 7,871 doses of levofloxacin that occurred during the same calendar day as any DTCC was selected for further review. Overall, 1,904 (77.1%) of 2,470 doses of oral levofloxacin reviewed were complicated by coadministration with at least one DTCC. On multivariable analysis, an increased number of prescribed medications was significantly associated with complete coadministration (per increase of one medication: OR, 1.05; CI95, 1.01–1.10; P = .036), whereas patient location in an ICU was protective (OR, 0.51; CI95, 0.30–0.87; P = .013). If our prevalence results are extrapolated to all patients receiving oral levofloxacin at our hospital, approximately one in three doses was complicated by coadministration.

Coadministration of fluoroquinolones with DTCCs is extremely common and significantly associated with polypharmacy.

Most reports of nosocomial infection (NI) prevalence have come from developed countries with established infection control programs. In developing countries, infection control is often not as well established due to lack of staff and resources. We exMnined the rate of N1 in our institution.

A point-prevalence study of N1 and antibiotic prescribing was conducted. On July 16 and 17, 2001, all inpatients were surveyed for N1, risk factors, pathogens isolated, and antibiotics prescribed and their indication. NIs were diagnosed according to CDC criteria. Cost of antibiotic acquisition was calculated by treatment indication.

Tertiary-care referral center in Malaysia.

All inpatients during the time of the study.

Five hundred thirty-eight patients were surveyed. Seventy-five had 103 NIs for a prevalence of 13.9%. The most common NIs were urinary tract infections (12.29-6), pneumonia (21.4%), laboratory-confirmed bloodstream infections (12.2%), deep surgical wound infections (11.2%), and clinical sepsis (22.4%). Pseudomonas aeruginosa, MRSA, and MSSA were the most common pathogens. Two hundred thirty-seven patients were taking 347 courses of antibiotics, for an overall prevalence of antibiotic use of 44%. N1 treatment accounted for 36% of antibiotic courses prescribed but 47% of antibiotic cost. Cost of antibiotic acquisition for N1 treatment was estimated to be approximately 2 million per year (Malaysian dollars).

Whereas the rate of N1 is relatively high at our center compared with rates from previous reports, antibiotic use is among the highest reported in any study of this kind. Further research into this high rate of antibiotic use is urgently required.