Effectiveness of Bath Wipes After Hematopoietic Cell Transplantation: A Randomized Trial.

Objective: Bacteremia is a leading cause of morbidity and mortality in children undergoing hematopoietic cell transplantation (HCT). Infections of vancomycin-resistant enterococci (VRE) and multidrug resistant (MDR) gram-negative rods (GNRs) are common in this population. Our objective was to assess whether experimental bath wipes containing silver were more effective than standard bath wipes containing soap at reducing skin colonization by VRE and MDR GNRs, and nonmucosal barrier injury bacteremia. Study Design: Patients undergoing autologous or allogeneic HCT in a tertiary referral center were randomized to receive experimental or standard bath wipes for 60 days post-HCT. Skin swabs were collected at baseline, discharge, and day +60 post-HCT. The rate of VRE colonization was chosen as the marker for efficacy. Results: Experimental bath wipes were well tolerated. Before the study, the rate of colonization with VRE in HCT recipients was 25%. In an interim analysis of 127 children, one (2%) patient in the experimental arm and two (3%) in the standard arm were colonized with VRE. Two (3%) patients had nonmucosal barrier injury bacteremia in the standard arm, with none in the experimental arm. MDR GNRs were not isolated. The trial was halted because the interim analyses indicated equivalent efficacy of the two methods. Conclusions: Skin cleansing with silver-containing or standard bath wipes resulted in very low and equivalent rates of bacteremia and colonization with VRE and MDR GNRs in children post-HCT. Future studies in other high-risk populations are needed to confirm these results.

Are toilet seats a vector for transmission of methicillin-resistant Staphylococcus aureus?

We studied the bacterial burden on toilet seats in a children's cancer hospital to validate a policy requesting that immunocompromised children use alcohol wipes on the seats prior to use of the toilets. Methicillin-resistant Staphylococcus aureus (MRSA) was recovered from 3.3% of hospital toilets when wipes were not in use. Use of wipes resulted in a 50-fold reduction in mean daily bacterial counts and eliminated MRSA.

Diagnosis of catheter-related bloodstream infections among pediatric oncology patients lacking a peripheral culture, using differential time to detection.

BACKGROUND: Current methods for in situ diagnosis of catheter-related bloodstream infections require concurrent collection of central venous catheter (CVC) and peripheral vein (PV) blood cultures. Both the pain and inconvenience of PV cultures are undesirable. METHODS: A prospective study was conducted (August 2002 to March 2004) to assess the accuracy of diagnosing catheter-related bloodstream infections based on the difference in time to detection of blood cultures drawn concurrently from 2 lumens of a multilumen CVC. This difference in time to detection between 2 lumens was compared with results of the standard criterion with paired CVC and PV blood cultures. RESULTS: Twenty-one infectious episodes were categorized as catheter-related bloodstream infections and 38 as non-catheter-related bloodstream infections. With a cutoff in difference in time to detection between 2 lumens of > or =180 minutes, the sensitivity of this test to diagnose a catheter-related bloodstream infection was 61% (95% confidence interval, 39-80%) and the specificity was 94% (95% confidence interval, 82-99%). In 4 of 7 episodes with false-negative results, the colony counts in cultures from both lumens were >400 colony-forming units/mL (maximal value reported), indicating the limitation of this method when both lumens of the catheter are colonized. With the pretest probability of catheter-related bloodstream infections ranging from 28% to 54%, the positive predictive value of a difference in time to detection between 2 lumens of > or =180 minutes for diagnosis of catheter-related bloodstream infections ranged from 81% to 93% and the negative predictive value ranged from 67% to 86%. CONCLUSION: Within the context of its limitations, this novel method provides an alternative for diagnosing catheter-related bloodstream infections among patients with a CVC, without PV cultures.

Difference in time to detection: a simple method to differentiate catheter-related from non-catheter-related bloodstream infection in immunocompromised pediatric patients.

Current methods for diagnosis of catheter-related infection (CRI) are cumbersome and may require removal of the central venous catheter (CVC). A prospective study was conducted to validate the difference in time to detection (DTD) of cultures of blood samples obtained simultaneously from a peripheral vein (PV) and from the CVC for differentiation of CRI and non-CRI. During a 15-month period, 9 episodes were categorized as CRI and 24 as non-CRI. The median DTD for patients with CRI was significantly higher than that for patients with non-CRI (457 vs. -4 min; P<.001). The optimum cutoff point for diagnosis of CRI was a DTD of > or =120 min (sensitivity, 88.9%; specificity, 100%). With pretest probability of CRI ranging from 28% to 54%, the positive predictive value of a DTD of > or =120 min for the diagnosis of CRI was 100%; the negative predictive value was 89%-96%. On the basis of findings from this study, which is the largest, to date, to involve pediatric patients with tunneled CVCs and the first to use paired quantitative blood cultures as a "criterion standard," DTD was found to be a simple, reliable tool for diagnosis of CRI in hospitals that use continuously read blood culture systems.

Optimizing blood culture practices in pediatric immunocompromised patients: evaluation of media types and blood culture volume.

BACKGROUND: The optimal use of blood cultures to determine the etiology of febrile episodes in neutropenic children has not been well-defined. METHODS: Single volume blood cultures using the Pediatric ISOLATOR System (ISO), were compared with variable, weight-based culture volumes using the BACTEC 9240 Culture System (BAC). Additionally the value of routinely inoculating the BACTEC MYCO/F LYTIC culture vial (MFL) as well as the BACTEC AEROBIC/F culture vial (AF) was examined. RESULTS: A total of 2620 cultures had both ISO and BAC inoculated; 182 cultures were positive (7.0% of cultures); 97.8% of positive cultures were detected by the BAC (AF and/or MFL) vs.46.2% detected by the ISO. The advantage of the BAC over the ISO was statistically significant for overall recovery of isolates and bloodstream infections, including most individual organism categories. There were only two instances (one each of histoplasmosis and candidemia) in which a blood stream infection was detected by ISO only. All the isolates judged to be contaminants were recovered by BAC only. AF detected significantly more coagulase-negative Staphylococcus spp. than the MFL. Of the isolates 16%, representing 14% of the bloodstream infections (including Gram-negative infections), were detected by the MFL only. Infections were detected more quickly by BAC than by ISO (P < 0.0001). Among the BAC media types, AF was faster than MFL (P < 0.0001). CONCLUSIONS: Optimal yield of blood cultures in immunocompromised pediatric patients included the use of BAC with a weight-based, graduated volume of culture inoculation and routine use of both AF and MFL.