Antimicrobial susceptibility of coagulase-negative staphylococci on tissue allografts and isolates from orthopedic patients.

Allograft infection occurs at a rate not different from that of similar procedures with large allografts or sterilized prosthetic devices and is usually caused by coagulase-negative staphylococci (CNS). CNS are feared for their limited antimicrobial susceptibility. We aimed at investigating this risk. CNS were isolated from 260 of 1461 allograft tissue grafts and compared with 384 consecutive clinical isolates from a general orthopedic population (258 patients). The CNS were identified and examined for their susceptibility to nine antibiotics used in routine practice. Staphylococcus epidermidis was the most commonly identified (35%) and the most resistant species of the allograft isolates. Comparing the overall antibiotic susceptibility patterns, clinical pathogens were significantly more resistant to six of the nine antibiotics (p < 0.01), namely penicillin, oxacillin, erythromycin, clindamycin, ofloxacin, and gentamicin. In conclusion, massive allograft infection is a well-known life-threatening surgical risk. However, we did demonstrate that allograft-related in contrast to orthopedic clinics-related CNS, are susceptible to commonly used first and second line antibiotics.