Microbiological monitoring of bone grafts: two years' experience at a tissue bank.

In the first two years of operation of a tissue bank, bone was processed on 63 occasions from 22 cadaveric donors and on 37 occasions from 185 living donors. A standardized protocol for microbiological sampling, culturing and interpretation of the results was developed. Semi-quantitative culture of washings of bone was performed on receipt by the tissue bank, and broth enrichment cultures of bone samples were performed at the end of processing, and again after irradiation. One bone donation was rejected because of heavy contamination with Klebsiella sp. on receipt, and contamination of six donations with Burkholderia cepacia was shown to have come from a water deionizer. Contamination of bone on receipt by the tissue bank decreased during the study period, probably related to increasing experience of staff harvesting bone. Microbiological surveillance of bone grafts protect recipients from infection, and is useful as a quality control of the process of bone banking.