Clinical experience with daptomycin for the treatment of patients with documented gram-positive septic arthritis

BACKGROUND: Septic arthritis is considered a rheumatologic emergency that can lead to join destruction and long-term impairment of joint function. Deptomycin is bactericidal in vitro against Staphylococcus aureus, the primary pathogen associated with septic arthritis. OBJECTIVE: To describe the use of daptomycin in patients with septic arthritis. METHODS: Data were collected as part of the Cubicin Outcomes Registry and Experience (CORE) program, a retrospective, observational, multicenter study, to describe the clinical use of daptomycin. Efficacy at the end of daptomycin therapy was determined by each center's investigator(s) as cure, improved, failure, or nonevaluable. Patients who had a diagnosis of septic arthritis, excluding concomitant ostemyelitis, as well as a positive culture by needle aspirate or deep tissue biopsy, were selected from the combined 2005 and 2006 CORE database. RESULTS: Twenty-two patients were included in this analysis. S. aureus was the most common pathogen isolated, with the majority resistant to methicillin. All patients received an antibiotic prior to daptomycin; in 7 patients, at least one of the prior antibiotics was continued with daptomycin. Almost two-thirds of patients received an antibiotic with daptomycin; rifampin was the most common. The median final dose and duration of daptomycin therapy were 5 mg/kg (range 3-6.3) and 22 days (range 3-52), respectively. Eighty-two percent of patients received daptomycin while admitted to a hospital; however, 68% received at least part of their daptomycin therapy as an outpatient. The outcomes of cure or improved were reported in 41% and 50% of the patients, respectively. Two adverse events were reported; neither was considered to be related to daptomycin. CONCLUSIONS: Daptomycin appeared to be effective when used as part of a treatment regimen for septic arthritis. These results require verification via a prospective clinical trial.