Defeating the Hidden Foe: Antibiotic Therapy and Clinical Outcomes of Cutibacterium acnes Spinal Implant Infections

Abstract

Background Cutibacterium acnes can cause spinal implant infections. However, little is known about the optimal medical management and outcomes of C. acnes spinal implant infections (CSII). Our study aims to describe the management of patients with CSII and evaluate the clinical outcomes. Methods We performed a retrospective cohort study of patients aged 18 years or older who underwent spinal fusion surgery with instrumentation between January 1, 2011, and December 31, 2020, and whose intraoperative cultures were positive for C. acnes: the primary outcome was treatment failure based on subsequent recurrence, infection with another organism or unplanned surgery secondary to infection. Results There were 55 patients with a median follow-up of 2 years (IQR 1.2-2.0). Overall, there were six treatment failures over 85.8 total person-years, for an annual rate of 7.0% (95% CI 2.6%-15.2%). Systemic antibiotic treatment was given to 74.5% (n = 41) of patients for a median duration of 352 days. In the subgroup treated with systemic antibiotics, there were 4 treatment failures (annual rate 6.3%, 95% CI 1.7%-16.2%), all of which occurred while on antibiotic therapy. Two failures occurred in the subgroup without antibiotic treatment (annual rate 8.8%, 95% CI 1.1% - 31.8%). Conclusion Our study found that the estimated annual treatment failure rate was slightly higher among patients who did not receive antibiotics. Of the six failures observed, four had to recurrence of C. acnes either on initial or subsequent treatment failures. More studies are warranted to determine the optimal duration of therapy for CSII.

Traditional Cultures versus Next Generation Sequencing for Suspected Orthopedic Infection: Experience Gained from a Reference Centre

“…The absence of these microorganisms in the syndromic panels aims to minimize the false positive results since some of them, such as Cutibacterium acnes or Staphylococcus epidermidis, can also be contaminants [19]. However, there is growing interest in the pathogenic roles of these bacteria, especially in some clinical scenarios such as shoulder infections [20], hardware-associated infections [21,22], and cases of chronic and indolent infections [16]. Therefore, further studies are needed to help to distinguish between true pathogens and contaminants.…”