To test the hypothesis that patients colonized with vancomycin-resistant Enterococcus (VRE) have a higher frequency of colonization or infection with other nosocomial pathogens than do patients who are not colonized with VRE.

A rectal swab culture survey was conducted to determine the point-prevalence of stool colonization with ceftazidime-resistant gram-negative bacilli in hospitalized patients with or without VRE stool colonization. For a 6-month period, the frequency of Clostridium difficile diarrhea and isolation of antibiotic-resistant (ie, ceftazidime-, piperacillin/tazobactam-, levofloxacin-, or trimethoprim/sulfamethoxazole-resistant) gram-negative bacilli, methicillin-resistant Staphylococcus aureus (MRSA), and non-albicans Candida species from clinical specimens other than stool was examined.

A Department of Veterans Affairs medical center.

All patients hospitalized in the acute care facility and one nursing home unit during a 1-week period in February 2001.

VRE-colonized patients had a higher point-prevalence of rectal colonization with ceftazidime-resistant gram-negative bacilli than did patients not colonized with VRE (17% vs 4%; P = .026). During a 6-month period, the VRE-colonized patients were more likely to have Clostridium difficile–associated diarrhea (26% vs 2%; P = .001), MRSA infection (17% vs 4%; P = .017), or colonization or infection with gram-negative bacilli resistant to 4 different antibiotics.

VRE-colonized patients in our institution have a higher frequency of colonization or infection with other nosocomial pathogens than do patients who are not colonized with VRE. This suggests that isolation measures implemented to control VRE could help limit the dissemination of other, coexisting pathogens.

To determine the natural history of colonization with vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and resistant gram-negative bacilli among long-term–care facility (LTCF) residents.

Observational cohort study.

A 355-bed LTCF with a ventilator unit and a subacute unit.

Residents with colonization or infection with VRE, MRSA or resistant gram-negative bacilli housed at the LTCF between December 1,1999, and February 29, 2000.

Cultures of clinical and surveillance sites were performed at regular intervals. Charts were reviewed for clinical characteristics associated with clearance of colonization. Kaplan–Meier curves were constructed to analyze the number of days to clearance of colonization.

Forty-nine residents had 65 episodes of colonization (27 VRE, 30 MRSA and 8 resistant gram-negative bacilli). Eighteen (28%) of the episodes cleared. The clearance rate was 2.7 episodes per 1,000 person-days. Clearance occurred significantly more often with resistant gram-negative bacilli colonization compared with VRE or MRSA colonization (6 [75%] vs 12 [21%]; P = .007; relative risk, 4.17; 95% confidence interval, 1.26 to 11.8). There was a trend toward longer use of antimicrobial agents among residents with persistent colonization. Infections occurred most frequently with MRSA The urinary tract was the most common site of infection.

Among LTCF residents, colonization with resistant gram-negative bacilli is four times more likely to clear than colonization with VRE or MRSA. Performance of surveillance cultures at regular intervals may reduce the need for contact precautions for LTCF residents with resistant gram-negative bacilli colonization.

To determine the impact of vancomycin-resistant enterococcal bacteremia on patient outcomes and costs by assessing mortality, excess length of stay, and charges attributable to it.

A population-based, matched, historical cohort study.

A 1,025-bed, university-based teaching facility and referral hospital.

Two hundred seventy-seven vancomycin-resistant enterococcal bacteremia case-patients and 277 matched control-patients identified between 1993 and 2000.

The crude mortality rate was 50.2% and 19.9% for case-patients and control-patients, respectively, yielding a mortality rate of 30.3% attributable to vancomycin-resistant enterococcal bacteremia. The excess length of hospital stay attributable to vancomycin-resistant enterococcal bacteremia was 17 days, of which 12 days were spent in intensive care units. On average, $77,558 in extra charges was attributable to each vancomycin-resistant enterococcal bacteremia. To adjust for severity of illness, 159 pairs of case-patients and control-patients, who had the same severity of illness (All Patient Refined-Diagnosis Related Group complexity level), were further analyzed. When patients were stratified by severity of illness, the crude mortality rate was 50.3% among case-patients compared with 27.7% among control-patients, accounting for an attributable mortality rate of 22.6%. Attributable excess length of stay and charges were 17 days and $81,208, respectively.

Vancomycin-resistant enterococcal bacteremia contributes significantly to excess mortality and economic loss, once severity of illness is considered. Efforts to prevent these infections will likely be cost-effective.

To determine the epidemiology of colonization with vancomycin-resistant Enterococcus (VRE) among intensive care unit (ICU) patients.

Ten-month prospective cohort study.

A 19-bed medical ICU of a 1,440-bed teaching hospital.

Patients admitted to the ICU had rectal swab cultures for VRE on admission and weekly thereafter. VRE-positive patients were cared for using contact precautions. Clinical data, including microbiology reports, were collected prospectively during the ICU stay.

Of 519 patients who had admission stool cultures, 127 (25%) had cultures that were positive for VRE. Risk factors for VRE colonization identified by multiple logistic regression analysis were hospital stay greater than 3 days prior to ICU admission (adjusted odds ratio [AOR], 3.6; 95% confidence interval [CI95], 2.3 to 5.7), chronic dialysis (AOR, 2.4; CI95, 1.2 to 4.5), and having been admitted to the study hospital one to two times (AOR, 2.3; CI95,1.4 to 3.8) or more than two times (AOR, 6.5; CI95, 3.7 to 11.6) within the past 12 months. Of the 352 VRE-negative patients who had one or more follow-up cultures, 74 (21%) became VRE positive during their ICU stay (27 cases per 1,000 patient-ICU days).

The prevalence of VRE culture positivity on ICU admission was high and a sizable fraction of ICU patients became VRE positive during their ICU stay despite contact precautions for VRE-positive patients. This was likely due in large part to prior VRE exposures in the rest of the hospital where these control measures were not being used.

To determine the distribution of vancomycin-resistant enterococci (VRE) cases in our hospital and those from outside of our hospital from 1993 through 1998.

Weekly rectal surveillance was instituted whenever there were two or more cases present in the units. Cases were divided into acquired in our hospital, acquired outside of our hospital (VRE positive after and within 72 hours of admission, respectively), and indeterminate. Hospital cases were attributed to the originating ward or intensive care unit (ICU) if patients were noted to be positive within 72 hours of transfer.

From 1993 to 1998, the rate of VRE per 1,000 admissions increased threefold, from 3.2 to 9.8, for the hospital. VRE cases acquired outside of the hospital increased by approximately 5% per year (r = 0.87; P = .03). The rate of VRE per 1,000 admissions increased 1.7-fold in the ICUs and 3.6-fold in the wards. The ICUs had an average of 75.3 cases per year, with the number of new cases per year increasing by approximately 9 (r = 0.80; P = .028). In the wards, there were an average of 22.0 new cases per year, with a slight upward trend of 3 additional new cases per year (r = 0.69; P = .64). There was a highly significant increasing linear trend (P = .0007) for VRE colonization and infection.

Although VRE still predominate in the ICUs, cases originating from outside of our hospital and the wards are becoming more common. VRE colonization remained more frequent than infection.

To characterize risk factors for Stenotrophomonas maltophilia bloodstream infection in oncology patients.

A 3:1 case–control study.

Stem Cell Transplant and Leukemic Center at Barnes–Jewish Hospital (St. Louis), a 1,442-bed, tertiary-care teaching hospital with a 26-bed transplantation ward.

From June 1999 to April 2001,13 patients with S. maltophilia bacteremia were compared with 39 control-patients who were on the transplantation unit on the same day as the case-patients' positive blood cultures. Information collected included patient demographics, medical history, history of transplantation, transplantation type, graft versus host disease, neutropenia, antibiotic use, chemotherapy, mucositis, diarrhea, the presence of central venous catheter(s), cultures, and concomitant infections.

Significant risk factors for S. maltophilia bacteremia included severe mucositis (7 [53.8%] of 13 vs 8 [20.5%] of 39; P = .034), diarrhea (7 [53.8%] of 13 vs 8 [20%] of 39; P = .034), and the use of metronidazole (9 [69.2%] of 13 vs 8 [20.5%] of 39; P = .002). In addition, the number of antibiotics used (median, 9 vs 5; P < .001), duration of mucositis (median, 29 vs 15 days; P = .032), and length of hospital stay (median, 34 vs 22 days; P = .017) were significantly different between case- and control-patients. Nine S. maltophilia isolates tested by pulsed-field gel electrophoresis were found to be distinctly different.

Interventions to ameliorate the severity of mucositis, reduce antibiotic pressure, prevent diarrhea, and promote meticulous central venous catheter care may help prevent S. maltophilia bloodstream infection in oncology patients. The role of gastrointestinal tract colonization as a potential source of S. maltophilia bacteremia in oncology patients deserves further investigation.

To explore the role of the community as a potential reservoir for Acinetobacter baumannii.

Antimicrobial resistance patterns and genotypes of A. baumannii isolates from patients in two Manhattan hospitals were compared with those of A. baumannii isolates from the hands of community members.

A total of 103 isolates from two hospitals (hospital A, 81; hospital B, 22) and 23 isolates from community residents were studied. Of the hospital isolates, 36.6% were multidrug resistant (hospital A, 68.2%; hospital B, 27.8%). In contrast, there were no multidrug-resistant isolates from the community (P < .005 between hospital and community). The prevalence of A. baumannii on the hands of community residents was 10.4% (23 of 222). By molecular typing, 42 strains of A. baumannii were identified. Of the isolates from hospital A and hospital B, 55.6% (45 of 81) and 68.2% (15 of 22), respectively, were indistinguishable or closely related. In contrast, most community (83.3%) isolates were unrelated (P = .001 between hospital and community).

Acinetobacter isolates from the community, characterized by a large variety of unrelated strains (83.3%), were distinct from the hospital isolates, of which 58.3% were closely related. The absence of multidrug-resistant strains in the community compared with 36.6% prevalence among hospital isolates suggests that the reservoir for epidemic strains resides in the hospital environment itself. To our knowledge, this is the first study to examine the community as a potential reservoir for hospital strains of A. baumannii.

To describe the implementation of the Canadian contingency plan for viral hemorrhagic fever (VHF) in response to a suspected case.

A 300-bed, tertiary-care, university-affiliated hospital.

A 32-year-old Congolese woman admitted to the hospital with suspected VHF in February 2001. Contact evaluation included hospital healthcare workers and laboratory staff.

Enhanced isolation precautions were implemented in the patient care setting to prevent nosocomial transmission. Contact tracing and evaluation of close and high-risk contacts with symptoms was conducted. Laboratory precautions included barrier precautions and diversion of specimens. Communication occurred to both hospital employees and the media.

Three high-risk contacts, 13 close contacts, and 60 casual contacts were identified. Two close contacts became symptomatic and required evaluation. Challenging process issues included tracing of laboratory specimens, decontamination of laboratory equipment, and internal and external communication. After 5 days, a transmissible VHF of public health consequence was ruled out in the index case.

Contingency plans for VHF can be implemented in an efficient and feasible manner. Contact tracing, laboratory issues, internal communication, and media interest can be anticipated to be the key challenges.