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The current approach for preventing hemolysis of red blood cells (RBCs) in major ABO-incompatible bone marrow (BM) grafts after infusion is to deplete RBCs from BM products before transplantation. Traditionally, manual density separation (MDS) using Ficoll-Hypaque (Cytiva Sweden AB, Uppsala, Sweden has been used to accomplish RBC depletion. This process yields good CD34+ cell recovery, but it requires open manipulation and is labor-intensive and time-consuming. We hypothesized that an alternative automated method using Haemonetics Cell Saver 5+ (Haemonetics Corporation, Boston, MA, USA) would offer equivalent RBC depletion and CD34+ cell recovery. Small marrow volumes from pediatric donors can be processed using Cell Saver (CS) without adding the third-party RBCs necessary for other automated methods. This retrospective analysis comprised data from 58 allogeneic BM grafts. RBC depletion and CD34+ cell recovery from BM using MDS (35 grafts) were compared with CS (14 grafts). Nine products underwent RBC depletion using CS with Ficoll (CS-F) when RBC volume was less than 125 mL. Linear regression analysis of log transformation of CD34+ cell recovery adjusted for log transformation of both baseline CD34+ cell content and baseline total volume showed no significant difference between MDS and CS (estimated coefficient, –0.121, P = 0.096). All products contained an RBC volume of less than 0.25 mL/kg post-processing. CD34+ cell recovery with CS-F was comparable to MDS and CS and suitable for pediatric recipients of allogeneic hematopoietic cell transplantation. We provide evidence that an automated method using Haemonetics Cell Saver 5+ achieves RBC depletion and CD34+ cell recovery comparable to MDS when adjusting for baseline factors. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background Genes conferring carbapenem resistance have disseminated worldwide among Gram-negative bacteria. Here we present longitudinal changes in clinically obtained Escherichia coli isolates from 1 immunocompromised pediatric patient. This report demonstrates potential for antibiotic resistance genes and plasmids to emerge over time in clinical isolates from patients receiving intensive anticancer chemotherapy and broad-spectrum antibiotics. Methods Thirty-three isolates obtained over 7 months from 1 patient were included. Clinical data were abstracted from the medical record. For each isolate, studies included phenotypic antibacterial resistance patterns, sequence typing, bacterial isolate sequencing, plasmid identification, and antibiotic resistance gene identification. Results Sites of isolation included blood, wound culture, and culture for surveillance purposes from the perianal area. Isolates were of 5 sequence types (STs). All were resistant to multiple classes of antibiotics; 23 (69.6%) were phenotypically resistant to all carbapenems. The blaNDM-5 gene was identified in 22 (67%) isolates, all of ST-167 and ST-940, and appeared to coincide with the presence of the IncFII and IncX3 plasmid. Conclusions We present unique microbiologic data from 33 multidrug-resistant E. coli isolates obtained over the course of 7 months from an individual patient in the United States. Two E. coli sequence types causing invasive infection in the same patient and harboring the blaNDM-5 gene, encoded on the IncX3 plasmid and the IncFII plasmid, were identified. This study highlights the emergence of multidrug-resistant bacteria on antibiotic therapy and the necessity of adequate neutrophil number and function in the clearance of bacteremia. [ABSTRACT FROM AUTHOR]