To identify risk factors for polymicrobial bloodstream infections (BSIs) in pediatric bone marrow transplant (BMT) outpatients attending a newly constructed clinic affiliated with a children's hospital.

All 30 outpatients treated at a new BMT clinic during September 10-21, 2007, were enrolled in a cohort study. The investigation included interviews, medical records review, observations, and bacterial culture and molecular typing of patient and environmental isolates. Data were analyzed using exact conditional logistic regression.

Thirteen patients experienced BSIs caused by 16 different, predominantly gram-negative organisms. Presence of a tunneled catheter (odds ratio [OR], 19.9 [95% confidence interval {CI}, 2.4-∞), catheter access (OR, 13.7 [95% CI, 1.8-∞]), and flushing of a catheter with predrawn saline (OR, 12.9 [95% CI, 1.0-766.0]) were independently associated with BSI. The odds of experiencing a BSI increased by a factor of 16.8 with each additional injection of predrawn saline (95% CI, 1.8-827.0). Although no environmental source of pathogens was identified, interviews revealed breaches in recommended infection prevention practice and medication handling. Saline flush solutions were predrawn, and multiple doses were obtained from single-dose preservative-free vials to avoid delays in patient care.

We speculate that infection prevention challenges in the new clinic, combined with successive needle punctures of vials, facilitated extrinsic contamination and transmission of healthcare-associated pathogens. We recommend that preservative-free single-use vials not be punctured more than once. Use of single-use prefilled saline syringes might prevent multiuse of single-use saline vials. Storage of saline outside a medication supply system might be advisable. Before opening new clinic facilities, hospitals should consider conducting a mock patient flow exercise to identify infection control challenges.

To determine the timing of community-onset Clostridium difficile–associated disease (CDAD) relative to the patient's last healthcare facility discharge, the association of postdischarge cases with healthcare facility–onset cases, and the influence of postdischarge cases on overall rates and interhospital comparison of rates of CDAD.

Retrospective cohort study for the period January 1, 2005, through December 31, 2005.

Catchment areas of 6 acute care hospitals in North Carolina.

We reviewed medical and laboratory records to determine the date of symptom onset, the dates of hospitalization, and stool C. difficile toxin assay results for patients with CDAD who had diarrhea and positive toxin–assay results. Cases were classified as healthcare facility–onset if they were diagnosed more than 48 hours after admission. Cases were defined as community-onset if they were diagnosed in the community or within 48 hours after admission, and were also classified on the basis of the time since the last discharge: if within 4 weeks, community-onset, healthcare facility–associated (CO-HCFA); if 4-12 weeks, indeterminate exposure; and if more than 12 weeks, community-associated. Pearson's correlation coefficient was used to assess the association between monthly rates of healthcare facility–onset, healthcare facility–associated (HO-HCFA) cases and CO-HCFA cases. We performed interhospital rate comparisons using HO-HCFA cases only and using both HO-HCFA and CO-HCFA cases.

Of 1046 CDAD cases, 442 (42%) were HO-HCFA cases and 604 (58%) were community-onset cases. Of the 604 community-onset cases, 94 (15%) were CO-HCFA, 40 (7%) were of indeterminate exposure, and 208 (34%) community-associated. A modest correlation was found between monthly rates of HO-HCFA cases and CO-HCFA cases across the 6 hospitals (r = 0.63, P<.001). Interhospital rankings changed for 6 of 11 months if CO-HCFA cases were included.

A substantial proportion of community-onset cases of CDAD occur less than 4 weeks after discharge from a healthcare facility, and inclusion of CO-HCFA cases influences interhospital comparisons. Our findings support the use of a proposed definition of healthcare facility–associated CDAD that includes cases that occur within 4 weeks after discharge.

To compare the cumulative incidence of infections acquired in the pediatric intensive care unit (PICU) and neonatal intensive care unit (NICU).

Estimation of the cumulative incidence of infections with data obtained from the Pediatric Prevention Network (PPN) point-prevalence survey and observed rates from the National Nosocomial Infections Surveillance (NNIS) system.

Ten hospitals participated in both the PPN survey and NNIS system.

All patients present on the PPN survey dates (August 4, 1999, or February 1, 2000) in the NICUs or PICUs of the PPN hospitals were included in the survey. Point prevalences for PICU-acquired and for NICU-acquired infections at these hospitals were calculated from the survey data. The cumulative incidence rates were estimated from the point prevalence rates using a standard formula and a standard method for calculating the time to recovery (ie, on the basis of the assumption that discontinuance of antimicrobial therapy indicates recovery from infection); alternate methods to judge the time to recovery from infection were also explored.

The average cumulative incidence of intensive care unit-acquired infection for NICUs and PICUs combined (all units), as measured by NNIS, was 14.1 cases per 100 patients; in comparison, the prevalence was 14.06 cases for 100 patients (median difference, —0.95 cases per 100 patients; 95% confidence interval, —4.6 to 5.0 cases per 100 patients), and the estimated cumulative incidence using the standard method of calculating the time to recovery was 13.8 cases per 100 patients (median difference, —1.5 cases per 100 patients; 95% confidence interval, —9.1 to 2.9 cases per 100 patients). Estimates of cumulative incidence using alternate methods for calculation of time to recovery did not perform as well (range, 4.9-100.9 cases per 100 patients). The average incidence density for all units, as measured by the NNIS system, was 6.8 cases per 1,000 patient-days, and the estimate of incidence density using the standard method of calculating the time to recovery was 3.6 cases per 1,000 patient-days (median difference, 4.3 cases per 1,000 patient-days; 95% confidence interval, 0.9 to 9.2 cases per 1,000 patient-days). Estimated incidence densities using alternate methods for determining recovery time correlated closely with observed incidence densities.

In this patient population, the simple point prevalence provided the best estimate of cumulative incidence, followed by use of a standard formula and a standard method of calculating the time to recovery. Estimation of incidence density using alternate methods performed well. The standard formula and method may provide an even better estimate of cumulative incidence than does simple prevalence in general populations.