To assess risk factors for colonization and nosocomial infection with ampicillin-resistant enterococci (ARE).

Patients with ampicillin-resistant enterococci were compared retrospectively by logistic regression analysis with controls harboring susceptible strains. ARE were characterized by whole plasmid DNA analysis and restriction enzyme analysis of plasmid (REAP) DNA with EcoRI.

The study was done at a 1,125 bed, tertiary-care teaching hospital in North Carolina with patients from whom enterococci were isolated from June 1, 1989, to March 30, 1991.

The final study group comprised 44 cases with nosocomially-acquired colonization or infection with ARE and 100 controls with ampicillin-susceptible strains. Clinical and epidemiological risk factors for ARE were abstracted by chart review.

After controlling for age and site of infection, patients with ARE were more likely to have been admitted previously to our hospital and to have received third-generation cepha-losporins and clindamycin. However, only advanced age and clindamycin therapy were independently associatedwith presence of ARE. REAP with EcoRI showed 20 groups of enterococci on 19 different wards.

These results suggest that ARE are endemic and multifocal in origin in our hospital and that advanced age and use of clindamycin are important selective risk factors for ARE colonization and infection (Infect Control Hosp Epidemiol1993;14:629-635).

To study the epidemiology of Yersinia enterocolitica infections in hospitalized patients and to determine the frequency of hospital-acquired infection and the modes of transmission within the hospital.

Descriptive study in which the clinical microbiology laboratory reported all positive Yersinia cultures to the infection control department; each case was investigated to determine the source of infection.

A 700-bed university teaching hospital.

All patients who were culture-positive for Y enterocolitica after admission to the University of Cincinnati Hospital during the 4-year period between 1987 and 1990.

Of 18 patients who were diagnosed with Yersinia infections, 8 (44%) were community-acquired. These patients were admitted with gastrointestinal symptoms and had their first positive cultures between days 1 and 5 of their hospitalizations. Five patients (28%) had hospital-acquired infections, having developed diarrhea after admission for unrelated problems, and became culture-positive between days 18 and 66. The remaining 5 patients could not be classified as either community- or hospital-acquired. These patients had gastrointestinal symptoms at the time of admission, but these could have been explained by other diseases. Their first positive stool cultures were not obtained until the second week or later during hospitalization, and 3 of these patients had negative stool cultures prior to a positive culture.

Although Y enterocolitica has not previously been recognized as a common hospital problem, at least 28% of our patients acquired their Yersinia infections in the hospital. In some cases, cross infections, transmitted by healthcare workers, occurred between patients. Four of the 18 infections occurred in patients with acquired immunodeficiency syndrome.

To investigate an outbreak of Serratia marcescens bacteremia among patients after general anesthesia.

A case-control study.

A 304-bed, pediatric teaching hospital.

Twenty-three pediatric patients who developed S. marcescens bacteremia within 2 weeks after general anesthesia between June 15 and September 22, 1999, were compared with 46 age-matched control-patients who had undergone procedures on the same clinical services of the hospital during the same period.

Cases were distributed over a wide range of surgical services and were not correlated with exposure to any of the surgical, anesthesia, or nursing staff. Case-patients were significantly more likely than control-patients to have received cefazolin (odds ratio [OR], 11.1; 90% confidence interval [CI90], 1.9 to 24.3) or to have had perioperative placement of a central vascular catheter (OR, 4.2; CI90, 1.2 to 18.8). The timing of the procedures of patients who subsequently developed S. marcescens bacteremia was significantly associated with the shifts of one or more of five operating room technicians (OR, 2.9 to 6.8) who were responsible for preparing intravenous fluids used both to reconstitute perioperatively administered antibiotics and to prime central vascular catheter assemblies.

Our findings are consistent with a pattern of intermittent contamination due to periodic breaches in sterile technique, rather than a point-source of contamination. The unique challenges that such a procedural breakdown presents to an epidemiologic investigation are discussed. This outbreak stresses the importance of providing comprehensive training in antisepsis when multifunctional personnel are incorporated into an operating room work environment.

To identify risk factors associated with an unexpected outbreak of pyrogenic reactions (PR) following intravenous gentamicin.

We conducted two cohort studies. PRs were defined as chills, rigors, or shaking within 3 hours after initiating the gentamicin infusion during the preepidemic (December 1, 1997-January 15,1998) or epidemic (May 1-June 15,1998) periods. We tested gentamicin vials for endotoxin using the limulus amebocyte lysate assay.

Inpatient services of a large community hospital in Los Angeles, California.

During the epidemic period, 22 (15%) of 152 patients developed documented PRs following intravenous gentamicin. PRs were more likely among patients receiving single daily dosing (SDD) than multiple daily dosing gentamicin (20/73 [27%] vs 2/79 [3%]; relative risk, 10.8; 95% confidence interval, 2.644.7). Laboratory analysis of gentamicin vials found endotoxin levels that were higher among Fujisawa-brand gentamicin (implicated brand) than gentamicin used after the outbreak terminated (non-implicated brand). Although endotoxin levels in the vials did not exceed US Pharmacopeia limits (1.7 endotoxin units/mg gentamicin), the use of SDD gentamicin may place patients at greater risk of receiving doses of endotoxin above the threshold for PRs in humans.

Reassessment of the acceptable amounts of endotoxin in gentamicin and other parenteral products should be considered when dosing intervals used in clinical practice change.

To assess the impact of a needleless intravenous (IV) connection system on the rate of reported intravenous-connection–related (IVCR) percutaneous injuries, and to assess user satisfaction, frequency of use, and barriers to use.

A pre-post inter vention design, with injury incidence rates being compared 3 years before and 1 year after hospitalwide device implementation; and a cross-sectional descriptive user satisfaction survey.

Two tertiar y-care teaching hospitals, one general and one pediatric, located in a large metropolitan medical center.

All IVCR percutaneous injuries reported to the employee health ser vices at both hospitals during the years from 1989 to 1991 and 1993.

Survey participants were selected randomly from licensed nursing employees at both hospitals.

IV connection system consisting of blunt plastic cannulas and compressed latex injection sites.

After device implementation, the IVCR injury rate was reduced 62.4% (rate ratio [RR], 0.38; 95% confidence inter val [CI95], 0.27-0.53) at the general hospital and 70.2% (RR, 0.30; CI95, 0.17-0.53) at the pediatric hospital. After adjusting for the reduction in injury rate due to factors other than device implementation, the IVCR injury rate was reduced 54.5% (adjusted RR, 0.46; CI95, 0.32-0.65) at the general hospital and 57.2% (adjusted RR, 0.43; CI95, 0.24-0.78) at the pediatric hospital. Approximately 94% of survey respondents (n=478, response rate=51%) were satisfied with the device and recommended continued use. However, needles still were being used for activities that could have been performed with the needleless system because of compatibility, accessibility, and other technical problems related to the device.

The device was effective in reducing the rate of reported IVCR percutaneous injuries and users were satisfied with the device, but barriers to universal use were identified.

Antibiotic overuse and misuse is a common problem in nursing homes. Antibiotic time-out (ATO) interventions have led to improvements in antibiotic uses in hospitals, but their impact in nursing homes remain understudied.

To evaluate the impact of a stewardship intervention, promoting use of ATOs on the frequency and types of antibiotic change events (ACEs) in nursing homes.

Controlled before-and-after intervention study.

Nursing homes in Wisconsin and Pennsylvania.

Data on antibiotic prescriptions in 11 nursing homes were collected for 25 months. We categorized ACEs as (1) early discontinuation, (2) class modification, or (3) administration modification. Class modification ACEs were further classified based on whether the change narrowed, expanded, or had no effect on bacterial spectrum coverage. Analyses were performed using a difference-in-difference (DiD) approach.

Of 2,647 antibiotic events initiated in study nursing homes, 376 (14.2%) were associated with an ACE. The overall proportion of ACEs did not significantly differ between intervention and control nursing homes. Early discontinuation ACEs increased in intervention nursing homes (DiD, 2.5%; P = .01), primarily affecting residents initiated on broad-spectrum antibiotics (DiD, 2.9%; P < .01). Class modification ACEs decreased in intervention nursing homes but remained unchanged in control nursing homes.

The impact of an ATO intervention in study nursing homes was mixed with increases in early discontinuation ACEs offset by reductions in class modification ACEs. More research on the potential value of ATO interventions in nursing homes is warranted.

1) To compare policies and procedures for distribution of influenza and pneumococcal vaccines to long-term care facilities for the elderly in Canada, 2) to determine vaccination rates of residents and staff, and 3) to describe vaccination and tuberculin skin testing programs in these facilities.

A cross-sectional survey consisting of telephone interviews and a mailed questionnaire was conducted in the spring of 1991. Telephone interviews were conducted with provincial/territorial epidemiologists. The questionnaire was sent to all (N = 1,520) Canadian long-term care facilities for the elderly with ≥ 25 beds.

There were 1,270 responding facilities (84%). The mean overall influenza vaccination rate for residents was 78.5%. The mean vaccination rate was higher in those provinces in which the vaccine was paid for by the government (79% versus 71%; P= 0.002). Only 19% of facilities reported staff vaccination rates >25%; rates again were higher in those provinces in which vaccine for staff was provided by the government. Pneumococcal vaccine was offered to residents in 12% of the facilities. The proportions of facilities with >10% and >75% of residents vaccinated were significantly higher in the provinces where the pneumococcal vaccine was recommended and paid for as compared with those where it was not (P<0.001 for both). Tuberculin skin testing programs for residents existed in 360 long-term care facilities (28%) across the country.

In 1990, the number of residents living in Canadian long-term care facilities who were vaccinated against influenza and Streptococcus pneumoniae was suboptimal. Staff influenza vaccination rates were very low across the country. Most facilities did not have a baseline tuberculin skin test status for their residents. Vaccination rates are higher in jurisdictions in which governments provide the vaccine without charge.

To achieve immunity to hepatitis B in healthcare workers who failed to respond to intramuscular vaccination and boosters.

An open prospective study of intradermal vaccination with recombinant hepatitis B vaccine.

A large community hospital in Connecticut.

Healthcare workers including physicians, nurses, and laboratory workers.

Immunization with high-dose intradermal recombinant hepatitis B vaccine, given in up to four doses, achieved immunity in 88% of healthcare workers who had previously been nonimmune.

We conclude that intradermal vaccination is efficacious in the majority of healthcare workers who failed to respond to intramuscular vaccine. Further studies, including randomized comparisons with intramuscular vaccine as well as studies of cell-mediated immunity, appear warranted.