Determination of Residual Antibiotics in Cryopreserved Heart Valve Allografts.

INTRODUCTION: Cardiovascular allografts are systematically incubated in antibiotics for their decontamination, and the antibiotics are removed before allograft implantation. We studied the occurrence of antibiotic residues in allograft valves. MATHODS: 12 experimental allografts were analyzed in this study. The concentration of the residual antibiotics was determined by high-performance liquid chromatography and the results were expressed as microgram per gram of allograft tissue. RESULTS: The initial analysis showed that only vancomycin HCl and lincomycin HCl were retained in the allograft, whereas no traces of polymyxin B sulfate were detected in the tissue samples. Furthermore, the values found for the antibiotic residues in the extracted solution from the allografts were similar to the initial results: Vancomycin and lincomycin were detected in very low concentrations and no polymyxin B residues were observed. According to the World Health Organization (WHO), the maximum daily doses for vancomycin, lincomycin and pol-ymyxin B are 2.0, 1.8 and 0.4 g, respectively. The thresholds for reporting degradation products are 0.05% for vancomycin and lincomycin and 0.1% for polymyxin B. The residual values for the two detected antibiotics were largely below 0.05%. CONCLUSIONS: Antibiotic residues in the allograft valves do not present any risk for their recipients. Increased allograft resistance to infections is probably due to the retention of antibiotics in the tissue.