Septic arthritis due to Clostridium ramosum.

Objectives: Clostridium species are anaerobic bacilli that are rarely reported as etiologic agents of infectious arthritis. Previous cases of arthritis caused by Clostridium ramosum have not been reported. We describe the first 2 cases of C. ramosum arthritis.

Methods: We reviewed the etiology of arthritis in our hospital during the previous 15 years.

Results: Both patients had underlying immunocompromising conditions and their infections involved a joint with preexisting disease: patient 1 had rheumatic arthritis and a prosthetic joint; patient 2, chronic renal failure on dialysis and hip osteoarthritis. The infection was hematogenously acquired and the course was indolent but destructive in both the cases. Management included open arthrotomy and resection arthroplasty. The infection had a persisting and relapsing course, and prolonged antibiotic treatment was required. In the literature review, we found 55 previous cases of arthritis caused by Clostridium species between 1966 and 2014; Clostridium perfringens was the most common infecting species; the infection was traumatically acquired in most of the cases. A total of 15 patients have been described with infections caused by C. ramosum; none had septic arthritis. The majority were elderly or immunocompromised adults. Proper collection, transportation and processing of clinical specimens is essential for diagnosing clostridial infections. More information about the best management of clostridial arthritis are needed.

Conclusions: We describe the first 2 cases of septic arthritis caused by C. ramosum. They shared several pathogenic and clinical features. The possibility of anaerobic arthritis should always be considered when collecting diagnostic specimens. An increasing number of clostridial arthritis cases are likely to be diagnosed in future years.