Impact of manufacturing, irradiation and filtration steps to bacterial contamination of autologous fibrin sealant

Background: Preoperative production of autologous fibrin sealant has become a routine procedure during the last years. As a certain percentage of blood products is contaminated with bacteria, contamination of plasma used for the production of fibrin sealant cannot be excluded. Especially in the orthopaedic setting, application of contaminated fibrin sealant can cause severe infections. Materials and methods: We contaminated plasma with Staphylococcus epidermidis, Corynebacterium striatum, Bacillus subtilis or Escherichia coli and produced fibrin sealant by cryoprecipitation and alcohol precipitation. Additionally, the products were gamma-irradiated at a dose of 30 Gy, frozen at -55 degreesC and filtered through a 0.2 mum filter after thawing. After each preparation step, samples were drawn and numbers of colony forming units were counted after incubation on agar plates. Results: Cryoprecipitation, irradiation, freezing at -55 degreesC, and alcohol precipitation have only little impact on numbers of colony forming units. Filtration through a bacterial filter results in a sterile product. Conclusion: Bacteria in plasma as a starting material for production of fibrin sealant survive all routine steps of production, including gamma irradiation and freezing. Filtration of the product through a qualified bacterial filter is the only safe means to provide a sterile product. (C) 2004 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.