In the Netherlands, the prevalence of methicillin resistance among Staphylococcus aureus isolates has been kept to less than 1% by using active screening programs and isolation. At the University Medical Center Utrecht (UMCU), an active screening program for methicillin-resistant S. aureus (MRSA) in the surgical intensive care unit (ICU) was implemented in 1986. Between 1992 and 2001, only 6 patients with MRSA were admitted to the surgical ICU. However, 4 of these 6 strains were able to spread to 23 other patients and 15 healthcare workers (HCWs). We were surprised by the epidemic behavior of these strains and wondered whether this was exceptional for S. aureus or whether methicillin-susceptible S. aureus (MSSA) was also spreading in the ICU.

A 2-month, prospective, observational study to investigate the incidence and spread of MSSA in the surgical ICU of UMCU and historical data collected during a 10-year period regarding MRSA.

A 10-bed surgical ICU in a 1,042-bed teaching hospital.

Weekly swabs revealed the presence of MSSA in 11 (24%) of 45 patients and 16 (22%) of 72 HCWs. Of all 4,105 patient–HCW contacts, there were only 21 episodes in which both the patient and the HCW were found to carry MSSA. With the use of pulsed-field gel electrophoresis, no identical strains could be identified.

In our surgical ICU, MRSA seems to spread more easily than MSSA, probably because of selection under antibiotic pressure or a still unknown intrinsic factor within MRSA.

Few children with tuberculosis (TB) have communicable disease, and most do not require isolation within the hospital. However, parents or adult visitors with unrecognized pulmonary TB may be a threat to hospital staff and other patients. We prospectively evaluated adults accompanying children hospitalized for suspected TB at a children's hospital to determine the frequency of undiagnosed, potentially contagious disease.

From 1992 to 1998, chest radiographs were obtained from adult caretakers accompanying 59 consecutive children admitted to Texas Children's Hospital with suspected TB. A child and his or her family were placed under Airborne Precautions only if the child or the accompanying adult exhibited characteristics of potentially contagious disease. Annual rates of tuberculin skin test conversion in hospital employees were obtained for the same period.

Of the 105 screened adults, 16 (15%) had previously undetected pulmonary TB. These adults were associated with 14 (24%) of the 59 children. In all instances in which the adult was the patient's parent, he or she was the source of infection to the child. Only 8 (13.5%) of the 59 children required isolation. Tuberculin skin test conversion from a negative to a positive reaction occurred in 127 employees (8 per 1,000 employee-years at risk). Only 4 of these 127 employees performed activities involving direct patient contact. None was in contact with families with a known potentially contagious adult or pediatric patient.

The risk of infection of healthcare workers from pediatric patients with primary TB appeared to be minimal, and most children with TB did not need isolation. Infection control efforts should be focused on accompanying adults and adult visitors. (Infect Control Hosp Epidemiol 2002;23:568-572).

To determine whether hand washing would increase with sustained feedback based on measurements of soap and paper towel consumption.

Prospective trial with a nonequivalent control group.

Open multibed rooms in the Omaha Veterans Affairs Medical Center's Surgical Intensive Care Unit (SICU) and Medical Intensive Care Unit (MICU).

Unit staff.

Every weekday from May 26 through December 8,1998, we recorded daytime soap and paper towel consumption, nurse staffing, and occupied beds in the SICU (intervention unit) and the MICU (control unit) and used these data to calculate estimated hand washing episodes (EHWEs), EHWEs per occupied bed per hour, and patient-to-nurse ratios. In addition, from May 26 through June 26 (baseline period) and from November 2 through December 8 (follow-up period), live observers stationed daily for random 4-hour intervals in the MICU and the SICU counted actual hand washing episodes (CHWEs). The intervention consisted of posting in the SICU, but not in the MICU, a graph showing the weekly EHWEs per occupied bed per hour for the preceding 5 weeks.

Directly counted hand washing fell in the SICU from a baseline of 2.68 ± 0.72 (mean ± standard deviation) episodes per occupied bed per hour to 1.92 ± 1.35 in the follow-up period. In the MICU, episodes fell from 2.58 ± 0.95 (baseline) to 1.74 ± 0.69. In the MICU, the withdrawal of live observers was associated with a decrease in estimated episodes from 1.36 ± 0.49 at baseline to 1.01 ± 0.36, with a return to 1.16 ± 0.50 when the observers returned. In the SICU, a similar decrease did not persist throughout a period of feedback. Estimated hand washing correlated negatively with the patient-to-nurse ratio (r = -0.35 for the MICU, r = -0.46 for the SICU).

Sustained feedback on hand washing failed to produce a sustained improvement. Live observers were associated with increased hand washing, even when they did not offer feedback. Hand washing decreased when the patient-to-nurse ratio increased.

Vancomycin-resistant enterococci (VRE) remain a significant nosocomial pathogen. Current guidelines of the Hospital Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) recommend the use of gowns and gloves for some interactions with VRE-infected or -colonized patients to prevent nosocomial transmission of VRE.

To assess the effect of disposable cover gowns on preventing nosocomial transmission of VRE.

Prospective study in a 16-bed medical intensive care unit of a university teaching hospital.

All patients who were at risk to acquire VRE, were admitted to the intensive care unit from August 1998 to January 1999, and had at least two perirectal cultures were included in the analysis of VRE acquisition.

VRE isolation precautions were changed from gowns and gloves to gloves alone.

VRE acquisition rates and risk factors for VRE acquisition.

The VRE acquisition rate was 1.80 cases per 100 days at risk in the gown and gloves period compared with 3.78 in the gloves only period (P= .04). In a proportional hazards model adjusted for length of stay, gloves only precautions with a hazard ratio of 2.5 (P = .02; 95% confidence interval, 1.2 to 5.3) were the only independent risk factor for VRE acquisition.

Our data lend support to current HICPAC recommendations for the use of cover gowns to decrease nosocomial transmission of VRE.

To determine baseline rates of primary bloodstream infection (BSI) among a large pool of patients receiving hemodialysis using standardized surveillance tools and methodology.

Prospective, descriptive analysis of primary BSI rates.

Ten hospital-based hemodialysis centers in Connecticut.

All patients receiving long-term hemodialysis in the participating facilities.

A total of 158 BSIs occurred during 142,525 dialysis sessions within a 12-month study period. Of the BSIs, 15.2% occurred in patients with fistula or graft access and 84.8% in patients with central venous catheter access (P < .001). Rates per 100 patient-years in centers ranged from 0 to 30.8, with a mean of 16.6. Rates per 1,000 dialysis sessions ranged from 0 to 2.1, with a mean of 1.1. Coagulase-negative staphylococci and Staphylococcus aureus (including methicillin-resistant S. aureus) accounted for 61% and Klebsiella or Enterobacter species for 14.6% of infections. Of the patients, 63.3% received vancomycin, 24.7% received cefazolin, and 41.7% received aminoglycosides. Rates declined in the second 6 months of the study from 1.4 to 0.8 infections per 1,000 dialysis sessions (P < .001).

Primary BSI rates varied widely among participating centers and declined during the study period. BSIs were strongly associated with central venous catheter access. Further studies are needed to determine the reasons for variance in rates between centers and among various types of hemodialysis access.

To measure the impact of orthopedic surgical-site infections (SSIs) on quality of life, length of hospitalization, and cost.

A pairwise-matched (1:1) case-control study within a cohort.

A tertiary-care university medical center and a community hospital.

Cases of orthopedic SSIs were prospectively identified by infection control professionals. Matched controls were selected from the entire cohort of patients undergoing orthopedic surgery who did not have an SSI. Matching variables included type of surgical procedure, National Nosocomial Infections Surveillance risk index, age, date of surgery, and surgeon.

Quality of life, duration of postoperative hospital stay, frequency of hospital readmission, overall direct medical costs, and mortality rate.

Fifty-nine SSIs were identified. Each orthopedic SSI accounted for a median of 1 extra day of stay during the initial hospitalization (P = .001) and a median of 14 extra days of hospitalization during the follow-up period (P = .0001). Patients with SSI required more rehospitalizations (median, 2 vs 1; P = .0001) and more total surgical procedures (median, 2 vs 1; P = .0001). The median total direct cost of hospitalizations per infected patient was $24,344, compared with $6,636 per uninfected patient (P = .0001). Mortality rates were similar for cases and controls. Quality of life was adversely affected for patients with SSI. The largest decrements in scores on the Medical Outcome Study Short Form 36 questionnaire were seen in the physical functioning and role-physical domains.

Orthopedic SSIs prolong total hospital stays by a median of 2 weeks per patient, approximately double rehospitalization rates, and increase healthcare costs by more than 300%. Moreover, patients with orthopedic SSIs have substantially greater physical limitations and significant reductions in their health-related quality of life.

To determine increased hospital stay and direct costs attributable to hospital-acquired, laboratory-confirmed bloodstream infection (BSI), and to evaluate the matching variable length of stay (LOS).

Retrospective (historical) cohort study with 1:2 matching in intensive care units and surgical wards.

A 2,000-bed university hospital in Rome, Italy.

All patients admitted between January 1994 and June 1995 who had hospital-acquired, laboratory-confirmed BSI were considered cases; all others were eligible as controls.

Two controls (A and B) were selected per case in a stepwise fashion. Controls in group A were selected according to the following six criteria: ward, gender, age, diagnosis, central venous catheter, and LOS equal to the interval from admission to infection in a matched case ± 20% (LOS ± 20%). Controls in group B were selected according to the first five criteria, but excluded LOS ± 20%.

One hundred five of 108 patients were each matched with two controls. The matching appropriateness score was greater than 90%. With the use of controls in groups A and B, the case-fatality rates attributable to hospital-acquired, laboratory-confirmed BSI were 35.2% and 40.9%, respectively; the estimated risk ratios for death were 2.60 and 3.52 (P = .0001), respectively. The increased hospital stay per case attributable to hospital-acquired, laboratory-confirmed BSI was 19.1 (mean) and 13.0 (median) days for matched pairs in control group A and 19.9 (mean) and 15.0 (median) days for matched pairs in control group B. With controls in group A, the cost of increased hospital stay per patient attributable to hospital-acquired, laboratory-confirmed BSI was Euro 15,413. The additional cost per patient due to treatment was Euro 943, making the overall direct cost Euro 16,356 per case.

This study should make it possible to estimate the cost of hospital-acquired, laboratory-confirmed BSI in most hospitals after adjusting for incidence rate. It also confirmed the use of LOS ± 20% as a matching variable to limit overestimation of increased hospital stay. To our knowledge, this is among the first such studies in Europe.

The role of rectal carriage of Staphylococcus aureus as a risk factor for nosocomial S. aureus infections in critically ill patients has not been fully discerned.

Nasal and rectal swabs for S. aureus were obtained on admission and weekly thereafter until discharge or death from 204 consecutive patients admitted to the surgical intensive care unit and liver transplant unit.

Overall, 49.5% (101 of 204) of the patients never harbored S. aureus, 21.6% (44 of 204) were nasal carriers only, 3.4% (7 of 204) were rectal carriers only, and 25.5% (52 of 204) were both nasal and rectal carriers. Infections due to S. aureus developed in 15.7% (32 of 204) of the patients; these included 3% (3 of 101) of the non-carriers, 18.2% (8 of 44) of the nasal carriers only, 0% (0 of 7) of the rectal carriers only, and 40.4% (21 of 52) of the patients who were both nasal and rectal carriers (P = .001). Patients with both rectal and nasal carriage were significantly more likely to develop S. aureus infection than were those with nasal carriage only (odds ratio, 3.9; 95% confidence interval, 1.18 to 7.85; P = .025). By pulsed-field gel electrophoresis, the infecting rectal and nasal isolates were clonally identical in 82% (14 of 17) of the patients with S. aureus infections.

Rectal carriage represents an underappreciated reservoir for S. aureus in patients in the intensive care unit and liver transplant recipients. Rectal plus nasal carriage may portend a greater risk for S. aureus infections in these patients than currently realized.

To investigate a perceived increase in central venous catheter (CVC)–associated bloodstream infections (BSIs) among pediatric hematology–oncology outpatients.

A case–control study.

A pediatric hematology–oncology outpatient clinic at Fresno Children's Hospital.

Pediatric hematology–oncology clinic outpatients with CVCs at Fresno Children's Hospital between November 1994 and October 1997.

A case-patient was defined as any hematology–oncology outpatient with a CVC-associated BSI at Fresno Children's Hospital from November 1996 to October 1997 (study period) without a localizable infection. To identify case-patients, we reviewed Fresno Children's Hospital records for all hematology–oncology clinic patients, those with CVCs and those with CVCs and BSIs. Control-patients were randomly selected hematology–oncology outpatients with a CVC but no BSI during the study period. Case-patient and control-patient demographics, diagnoses, caretakers, catheter types, catheter care, and water exposure were compared.

Twenty-five case-patients had 42 CVC-associated BSIs during the study period. No significant increase in CVC-associated BSI rates occurred among pediatric hematology–oncology patients. However, there was a statistically significant increase in nonendogenous, gram-negative (eg, Pseudomonas species) BSIs during summer months (May–October) compared with the rest of the year. Case-patients and control-patients differed only in catheter type; case-patients were more likely than control-patients to have a transcutaneous CVC. Summertime recreational water exposures were similar and high in the two groups.

Hematology–oncology clinic patients with transcutaneous CVCs are at greater risk for CVC-associated BSI, particularly during the summer. Caretakers should be instructed on proper care of CVCs, particularly protection of CVCs during bathing and recreational summer water activities, to reduce the risk of nonendogenous, gram-negative BSIs.

To determine the percentage of cross-transmissions in an intensive care unit (ICU) with high nosocomial infection (NI) rates according to the data of the German Nosocomial Infection Surveillance System.

A 14-bed surgical ICU of a 1,300-bed, tertiary-care teaching hospital.

Prospective surveillance of NIs during a period of 9 months. If an NI was present, the isolates of the following indicator pathogens were stored and typed by species: Staphylococcus aureus, Enterococcus species, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacter species. Pulsed-field gel electrophoresis was performed for typing of S. aureus strains and arbitrarily primed polymerase chain reaction was applied for the other pathogens. The presence of two indistinguishable strains in two patients was considered as one episode of cross-transmission.

Two hundred sixty-two patients were observed during a period of 2,444 patient-days; 96 NIs were identified in 59 patients and the overall incidence density of NI was 39.3 per 1,000 patient-days. For 104 isolates, it was possible to consider typing results. Altogether, 36 cross-transmissions have lead to NIs in other patients. That means at least 37.5% of all NIs identified were due to cross-transmissions.

Because of the method of this study, the percentage of NIs due to cross-transmission identified for this ICU is an “at least number”. In reality, the number of cross-transmissions, and thus the number of avoidable infections, may have been even higher. However, it is difficult to assess whether the percentage of NIs due to cross-transmission determined for this ICU may be the crucial explanation for the relatively high infection rate in comparison to other surgical ICUs.

Investigate and control an increase in bloodstream infections (BSIs) in an outpatient hemodialysis center.

A retrospective cohort study was conducted for patients receiving dialysis at the center from February 2000 to April 2001. A case–control study compared microbiological data for all BSIs that occurred during the study period with those for BSIs that occurred during a baseline period Qanuary 1999 to January 2000). BSI rates before and after a 1-month intervention (May 2001) were assessed. A case was defined as a new BSI during the study period.

The outbreak was polymicrobial, with approximately 30 species. The baseline BSI rate was 0.7 per 100 patient-months. From February 2000 to April 2001, the BSI rate increased to 4.2 per 100 patient-months. Overall, 75% of the BSIs were associated with central venous catheters (CVCs), but CVC use did not fully explain the increase in BSIs. In January 2000, when the center changed ownership, prepackaged CVC dressing kits and biweekly infection control monitoring were discontinued. Beginning in May 2001, staff were educated on CVC care, chlorhexidine replaced povidone-iodine for cutaneous antisepsis, gauze replaced transparent dressings, antimicrobial ointments containing polyethylene glycol at CVC exit sites were discontinued, and patients with CVCs were educated on cutaneous hygiene. After the intervention period, by October 2001, rates decreased to less than 1 BSI per 100 patient-months.

Proper cutaneous antisepsis and access site care is crucial in preventing BSIs in patients receiving hemodialysis. Infection control programs, staff and patient education, and use of optimal antisepsis agents or prepackaged kits are useful toward this end.

Several hospitals opting not to use active surveillance cultures to identify carriers of vancomycin-resistant Enterococcus (VRE) have reported that adoption of other parts of the Centers for Disease Control and Prevention guideline for controlling VRE has had little to no impact. Because use of surveillance cultures and contact isolation controlled a large outbreak at this hospital, their costs were estimated for comparison with the excess costs of VRE bacteremias occurring at a higher rate at a hospital not employing these measures.

Two university hospitals.

Inpatients deemed high risk for VRE acquisition at this hospital underwent weekly perirectal surveillance cultures. Estimated costs of cultures and resulting isolation during a 2-year period were compared with the estimated excess costs of more frequent VRE bacteremias at another hospital of similar size and complexity not using surveillance cultures to control spread throughout the hospital.

Of 54,052 patients admitted, 10,400 had perirectal swabs taken. Cultures and isolation cost an estimated $253,099. VRE culture positivity was limited to 193 (0.38%) and VRE bacteremia to 1 (0.002%) as compared with 29 bacteremias at the comparison hospital. The estimated attributable cost of VRE bacteremia at the comparison hospital of $761,320 exceeded the cost of the control program at this hospital by threefold.

The excess costs of VRE bacteremia may justify the costs of preventive measures. The costs of VRE infections at other body sites, of deaths from untreatable infections, and of dissemination of genes for vancomycin resistance also help to justify the costs of implementing an effective control program.

To compare the occurrence of Clostridium difficile among inpatients infected with human immunodeficiency virus (HPV) in two different hospitals.

Prospective, observational study.

Specialized HPV inpatient units.

HIV-infected inpatients at Cook County Hospital (CCH) and Rush Presbyterian St. Luke's Medical Center (RPSLMC).

A clinical and epidemiologic assessment of patient risk factors for C. difficile was performed. C. difficile isolates found on stool, rectal, and environmental cultures were typed by pulsed-field gel electrophoresis.

Twenty-seven percent of patients admitted to CCH versus 4% of patients admitted to RPSLMC had positive cultures for C. difficile (P = .001). At CCH, 14.7% of environmental cultures were positive versus 2.9% at RPSLMC (P = .002). Risk factors for C. difficile acquisition included hospitalization at CCH, more severe HrV, use of acyclovir and H2-blockers, and longer hospital stay. Patients admitted to CCH were taking more antibiotics, had longer hospital stays, and more frequently had a history of C. difficile infection. During the study, two strains (CD1A and CD4) extensively contaminated the CCH environment. However, only CD1A caused an outbreak.

The C. difficile acquisition rate at CCH was sevenfold higher than that at RPSLMC, and CCH had a more contaminated environment Differences in patient acquisition rates likely reflect a greater prevalence of traditional C. difficile risk factors and a concurrent outbreak at CCH. Although two strains heavily contaminated the environment at CCH, only one caused an outbreak, suggesting that factors other than the environment are important in initiating C. difficile outbreak.

We report a case of congenital tuberculosis in a neonatal intensive care unit (NICU) and the management of exposure to other neonates in the hospital. We review the literature regarding congenital tuberculosis and management of exposures in the NICU.

Case report and a survey of exposures with a 3-month follow-up.

Urban hospital.

Neonates exposed to a case of congenital tuberculosis.

Exposure to tuberculosis was treated with isoniazid. Purified protein derivative tests were placed at base-line and 3 to 4 months after exposure. Chest radiographs were performed if clinically indicated.

Congenital tuberculosis was diagnosed in our patient at 21 days of age during a prolonged hospital course. After initiation of anti-tuberculous medications, the patient gradually recovered from his illness. While he was treated in the NICU, there were 37 potentially exposed infants. Of these, 36 were administered tuberculin skin tests (average age, 1.7 months), all of which were read as 0 mm of induration. Of those 37, 35 began prophylaxis with isoniazid, and 30 were able to complete treatment with a minimum of 3 months of isoniazid therapy. Of those 30, two infants received 6 months of therapy. Additionally, 29 of the 37 infants had chest radiographs, none of which showed suspicious infiltrates or adenopathy. Finally, 30 of the 36 infants had repeat tuberculin skin tests at 3 months, all of which were read as 0 mm of induration (average age, 3.7 months).

Congenital tuberculosis is an uncommon disease that requires early diagnosis for successful therapy and vigilant follow-up of potential exposures in the NICU. (Infect Control Hosp Epidemiol 2002;23:573-579).