Les prélèvements à visée bactériologique en chirurgie de reprise : quand, comment, quelles conclusions thérapeutiques ?

Abstract

Bacteriological sampling in orthopedic revision surgery for arthroplasty or internal fixation raises several questions. 1) When? And should sampling be systematic? Sampling should not be systematic in revision surgery, but only in case of suspected infection, in which case provisional antibiotic therapy should be systematically implemented. 2) How? Which tissues, how many and what transport? Only deep samples, preferably taken without ongoing antibiotic therapy, allow reliable interpretation of results. The optimal number of intraoperative samples is 5, or 3 if the laboratory uses seeding in aerobic and anaerobic vials. Samples should be transported to the laboratory within 2 hours, at room temperature. 3) What conclusions can be drawn, using what references? There are several classifications, leading to divergent interpretation. The EBJIS (European Bone and Joint Infection Society) classification showed the best sensitivity in a multicenter study. 4) What duration of antibiotic therapy, and how to proceed if it cannot be achieved? Duration should be 14 days, or 21 days in case of prior treatment by cyclins, clindamycin, rifampicin or drugs with a very long half-life such as lipoglycopeptides or quinolones, so as not to render the samples negative, except when medico-surgical treatment is required urgently. 5) Microbiological sampling, or antibiotic prophylaxis? Pursuing prophylactic antibiotic therapy during bone and joint implant revision does not greatly impair the value of intraoperative sampling. However, evidence of benefit of continuing antibiotic prophylaxis during revision arthroplasty is lacking. 6) What samples for atypic infection? Atypic micro-organisms (mycobacteria, yeasts, etc.) require specific screening, guided by the clinical context and discussed before sampling is carried out.Level of evidence: V; expert opinion.