To describe an outbreak of hepatitis C in a clinical research study.

Observational study.

Tertiary-care hospital.

Healthcare workers who volunteered to be subjects in a study of the metabolic effects of inhaled and oral corticosteroids who were unwittingly exposed to hepatitis C virus (HCV).

Epidemiological investigation and serological analyses.

One chronic carrier of HCV was identified. Four fellow workers volunteering in the studies became infected with HCV, with 96% homology among strains. There was no evidence of spread from infected healthcare workers to patients on whom they had performed arterial punctures (2 of 214 positive, unrelated to each other and to the outbreak strain).

Infection control standards in clinical research must be maintained vigorously to prevent transmission of blood-borne pathogens such as HCV.

To study postoperative infections in hospital and after discharge, and to identify the risk factors for such infections.

Prospective cohort study, with telephone follow-up for 1 month after hospital discharge.

The general surgery service of a tertiary hospital in Spain.

In-hospital and postdischarge surgical-site infection (SSI), always confirmed by a physician.

Of the 1,506 patients initially enrolled, 29 died during hospital stay, and 33 were lost to postdischarge follow-up. An SSI was identified prior to discharge in 123 patients and after discharge in 103. For several variables (age, serum albumin, glycemia, lengths of preoperative and postoperative hospital stay, etc), there were no differences between patients with postdischarge SSI and noninfected patients; however, there were differences detected between patients with postdischarge SSI and in-hospital SSI, as well as between patients with in-hospital SSI and noninfected patients. The analysis of risk factors showed that most predictors for in-hospital SSI did not behave in the same manner for postdischarge SSI. Stepwise logistic regression only identified chemoprophylaxis, age (advanced age was a preventive factor), and body mass index as independent risk factors for postdischarge SSI. Differences in risk factors between in-hospital and postdischarge SSIs remained even after controlling for time from operation to diagnosis.

Most predictors of in-hospital SSI were not predictors of postdischarge SSI.

To evaluate the possible presence of vancomycin-resistant Staphylococcus aureus (VRSA) in a Brazilian hospital.

Epidemiological and laboratory investigation of nosocomial VRSA

140 methicillin-resistant S aureus strains isolated between November 1998 and October 1999 were screened for susceptibility to vancomycin. The screening was carried out by using brain-heart infusion agar (BHIA) supplemented with 4, 6, and 8 μg/mL of vancomycin. The minimum inhibitory concentration (MIC) determination was carried out as standardized by the National Committee for Clinical Laboratory Standards using the broth macrodilution, agar-plate dilution, and E-test methods.

Hospitalized patients exposed to vancomycin.

5 of the 140 isolates had a vancomycin MIC of 8 μg/mL by broth macrodilution, agar plate dilution, and E-test methods. Four VRSA strains were isolated from patients in a burn unit who had been treated with vancomycin for more than 30 days, and one from an orthopedic unit patient who had received vancomycin treatment for 7 days. Pulsed-field gel electrophoresis characterized four of the VRSA strains as belonging to the Brazilian endemic clone. All five strains were negative for vanA, vanB, and vanC genes by polymerase chain reaction. Transmission electron microscopy of the five strains revealed significantly thickened cell walls. One patient died due to infection caused by the VRSA strain.

This is the first report of isolation of VRSA in Brazil and the first report of isolation of multiple VRSA strains from one facility over a relatively short period of time. This alerts us to the possibility that VRSA may be capable of nosocomial transfer if adequate hospital infection control measures are not taken.

To review clinical experience with methicillin-resistant Staphylococcus aureus (MRSA) in tertiary-care hospitals in Jeddah, Saudi Arabia.

Retrospective review for the year 1998.

Two tertiary-care hospitals.

Results of MRSA-positive cultures of clinical specimens obtained as part of investigations for suspected infections were retrieved from the microbiology laboratories' records. Charts of patients were reviewed, with standardized data collection.

Of 673 S aureus isolates identified, 222 (33%, or 6.8 isolates/1,000 admissions) were MRSA Overall MRSA prevalence was 2% in 1988. Nosocomial acquisition occurred in 84.2% of cases. All age groups were affected, and 52% of patients had at least one comorbidity. MRSA prevalence was highest in the intensive care units (26.6% of all isolates), the medical wards (24.8%), and the surgical wards (19.8%). Seventy-three percent of isolates caused infection; the rest represented colonization. Surgical wounds (35.2%), the chest (29%), and central venous catheters (13%) were the most common sites of infection. Bacteremia occurred in 15.4% of patients. Local signs (84%) and fever (75.9%) were the most common clinical manifestations. Respiratory distress and septic shock occurred in 30.2% and 13.6% of cases, respectively. Of 162 patients with MRSA infection and 60 patients with MRSA colonization, 95.7% and 70% received antibiotics in the preceding 6 weeks, respectively (P<.0001). The total mortality of patients with MRSA infection was 53.7%: 36.4% as a result of MRSA infection and 17.3% as a result of other causes.

The prevalence of MRSA is high and rapidly increasing in the two hospitals, as it is worldwide. Control measures to prevent die spread of MRSA in hospitals should continue, with reinforcement of hygienic precautions and development of policies to restrict the use of antibiotics.

To identify risk factors and describe the microbiology of catheter exit-site and hub colonization in neonates.

During a period of 2 years, we prospectively investigated 14 risk factors for catheter exit-site and hub colonization in 862 central venous catheters in a cohort of 441 neonates. Cultures of the catheter exit-site and hub were obtained using semiquantitative techniques at time of catheter removal.

A neonatal intensive care unit at a university hospital.

Catheter exit-site colonization was found in 7.2% and hub colonization in 5.3%. Coagulase-negative staphylococci were predominant at both sites. Pathogenic flora were found more frequently at the catheter hub (36% vs 14%; P<.05). Through logistic regression, factors associated with exit-site colonization were identified as umbilical insertion (odds ratio [OR], 8.1; 95% confidence interval [CI95], 2.35-27.6; P<.001), subclavian insertion (OR, 54.6; CI95, 12.2-244; P<.001), and colonization of the catheter hub (OR, 8.9; CI95,3.5-22.8; P<.001). Catheter-hub colonization was associated with total parenteral nutrition ([TPN] OR for each day of TPN, 1.056; CI95,1.029-1.083; P<.001) and catheter exit-site colonization (OR, 6.11; CI95, 2.603-14.34; P<.001). No association was found between colonization at these sites and duration of catheterzation and venue of insertion, physician's experience, postnatal age and patient's weight, ventilation, steroids or antibiotics, and catheter repositioning.

These data support that colonization of the catheter exit-site is associated with the site of insertion and colonization of the catheter hub with the use of TPN. There is a very strong association between colonization at both catheter sites.

To evaluate the implementation and efficacy of selected Centers for Disease Control and Prevention guidelines for preventing spread of Mycobacterium tuberculosis.

Analysis of prospective observational data.

Two medical centers where outbreaks of multidrug-resistant tuberculosis (TB) had occurred.

All hospital inpatients who had active TB or who were placed in TB isolation and healthcare workers who were assigned to selected wards on which TB patients were treated.

During 1995 to 1997, study personnel prospectively recorded information on patients who had TB or were in TB isolation, performed observations of TB isolation rooms, and recorded tuberculin skin-test results of healthcare workers. Genetic typing of M tuberculosis isolates was performed by restriction fragment-length polymorphism analysis.

We found that only 8.6% of patients placed in TB isolation proved to have TB; yet, 19% of patients with pulmonary TB were not isolated on the first day of hospital admission. Specimens were ordered for acid-fast bacillus smear and results received promptly, and most TB isolation rooms were under negative pressure. Among persons entering TB isolation rooms, 44.2% to 97.1% used an appropriate (particulate, high-efficiency particulate air or N95) respirator, depending on the hospital and year; others entering the rooms used a surgical mask or nothing. We did not find evidence of transmission of TB among healthcare workers (based on tuberculin skin-test results) or patients (based on epidemiological investigation and genetic typing).

We found problems in implementation of some TB infection control measures, but no evidence of healthcare-associated transmission, possibly in part because of limitations in the number of patients and workers studied. Similar evaluations should be performed at hospitals treating TB patients to find inadequacies and guide improvements in infection control.

To identify the routes of transmission in a nosocomial outbreak of hepatitis C virus (HCV) infection.

Epidemiological investigation, including screening for HCV of hospitalized patients, and a retrospective cohort study, review of hygiene and medical practices, and molecular comparison of HCV isolates.

A specialized care unit for cystic fibrosis (CF) and diabetic patients at an acute-care facility in the south of France.

Of the 57 CF patients (age in 1995: 2-28 years), 38 (66.7%) were tested and 22 (57.9%) were anti-HCV positive. Eight (50%) of 16 patients with anti-HCV antibody tested by polymerase chain reaction were viremic. No patients had received blood products or had any history of intravenous drug use. All 18 (100%) patients with CF who had ever undergone self-monitoring of capillary blood glucose in the unit were anti-HCV positive, compared to 4 (20%) of 20 who had not (relative risk, 5.0; 95% confidence interval, 2.1-12.0). Seventy (39.5%) of the patients with diabetes were screened for anti-HCV; 12 (18.8%) tested positive, with 3 (25%) positive for HCV-RNA. Patients with diabetes had routine capillary blood glucose monitoring while hospitalized and shared with CF patients the same spring-triggered devices for capillary blood glucose monitoring. The disposable platform of the devices was not changed between patient use. All HCV isolates belonged to the type 1, subtype b, and phylogenetic analysis showed a close homology by sequencing of NS5b and E2/HVR regions.

As reported earlier for the hepatitis B virus, shared spring-triggered devices for capillary blood glucose monitoring by finger puncture may transmit HCV. Strict application of Standard Precautions procedures is warranted in any healthcare setting.