Abstract
Aim
Corynebacterium is a rare etiologic agent of BJI. We aimed to describe this rare clinical condition and to assess treatment failure determinants.
Method
All adult patients with proven Corynebacterium BJI (i.e. consistent clinical/radiological signs, AND ≥2 reliable positive bacteriological samples, AND treated as such) were included in a retrospective cohort study. After cohort description, determinants of treatment failure (i.e, infection persistence, relapse, requirement of additional surgical procedure, and BJI-related death) were determined using stepwise logistic regression and Kaplan Meier curve analysis.
Results
The 51 included BJI were more frequently chronic (88.2%), orthopaedic device-related (ODI, 74.5%) and polymicrobial (78.4%). Surgery was performed in 92.2% of cases, and considered as appropriate in 76.5% of them. The main first-line antimicrobials were glycopeptides (68.6%), betalactams (50%) and/or clindamycin (10.0%). Three (5.9%) patients received daptomycin as part of first-line regimen, and 8 (15.7%) at any point of treatment. After a follow-up of 60.7 (IQR, 30.1–115.1) weeks, 20 (39.2%) treatment failures were observed, including 4 (20%) Corynebacterium-documented relapse. Independent risk factors were initial biological inflammatory syndrome (OR 16.1; p=0,030) and inappropriate surgical management (OR 7.481; p=0.036). Interestingly, all patients receiving daptomycin as part of first-line regimen failed (p<0.001), including one patient with a Corynebacterium-documented relapse with a daptomycin increased MIC. Among patients with ODI, survival curve analysis disclosed a worst prognosis in case of prosthetic joint infection (p=0.030), unappropriate surgical management (p=0.029) and daptomycin use as first-line regimen (p<0.001).
Conclusions
Corynebacterium BJI is a poorly known condition, frequently chronic and polymicrobial. An important rate of failure was observed, associated with inappropriate surgical management and daptomycin use as part of first-line regimen. As described for other clinical conditions such as infective endocarditis, daptomycin should be avoid or used in combination therapy to prevent resistance selection and treatment failure.
