title: Microbial contamination of hematopoietic progenitor cell products.
abstract: BACKGROUND
  Microbial screening for contamination is a part of hematopoietic progenitor cell (HPC) collection and infusion procedure. We aimed to find out our microbial contamination rates during collection, processing and infusion steps of HPC products. We also evaluated the clinical course of patients who received contaminated HPC products.
  
  
  METHODS
  We retrospectively analyzed microbial contamination records of HPC grafts between 2010 and 2012. HPC products of autologous donors were evaluated for contamination at three steps: at the end of mobilization, following processing with DMSO and just before stem cell infusion. Grafts of allogeneic donors were assessed only before HPC transplantation (HCT). Microbiological analysis of HPC samples were performed with an automated system (BacT/Alert®).
  
  
  RESULTS
  During the study period a total of 492 mobilization procedures were performed on 329 (214 autologous and 115 allogeneic) donors. Bacterial contamination has been detected in 103 of 1630 samples (6%). Ninety-seven out of 1162 blood samples (8%) from 265 patients who were treated with HCT were contaminated. Forty-six patients (41 autologous and 5 allogeneic) were transplanted with contaminated HPC products. During HCT 42 patients experienced febrile neutropenic attack and 34 of them had positive blood culture results. In none of these 34 patients the isolated pathogens were the same organisms with those found in the final contaminated stem cell product before stem cell infusion. None of the patients who received contaminated products died because of sepsis within the posttransplant 30days. There was no significant difference between patients who received contaminated and non-contaminated products in terms of the first day of fever, duration of fever, engraftment kinetics and duration of hospitalization.
  
  
  CONCLUSIONS
  Our results suggest that microbial contamination of HPC products is an issue to be prevented, although it may not have a major impact on the general success of HCT.
authors.affiliation: Ankara Oncology Education and Research Hospital, Hematology and Stem Cell Transplantation Clinic, Ankara, Turkey. drsinemnamdaroglu@gmail.com
authors.forename: Sinem
authors.initials: S
authors.lastname: Namdaroğlu
authors.forename: Emre
authors.initials: E
authors.lastname: Tekgündüz
authors.forename: Sinem Civriz
authors.initials: SC
authors.lastname: Bozdağ
authors.forename: Gamze
authors.initials: G
authors.lastname: Durgun
authors.forename: Abdurrahman
authors.initials: A
authors.lastname: Sarıca
authors.forename: Itır Şirinoğlu
authors.initials: IŞ
authors.lastname: Demiriz
authors.forename: Serife
authors.initials: S
authors.lastname: Koçubaba
authors.forename: Gülşen
authors.initials: G
authors.lastname: Iskender
authors.forename: Omür
authors.initials: O
authors.lastname: Kayıkçı
authors.forename: Fevzi
authors.initials: F
authors.lastname: Altuntaş
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001331:Automation; D001419:Bacteria / Q000302:isolation & purification*; D002648:Child; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects* / Q000379:methods*; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000382:microbiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013048:Specimen Handling / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult