282. Side Effects and Outcomes of 94 Patients Treated with Daptomycin as Salvage Therapy for  Orthopaedic Infection
Session: Poster Abstract Session: Antimicrobial Therapy: Clinical Studies
Friday, October 21, 2011
Room: Poster Hall B1

Background: Small case series have described successful off-label use of Daptomycin for orthopaedic infections when first line therapy was intolerable. We report outcomes of Daptomycin salvage therapy at 6 & 12 month follow-up in a cohort of 94 patients with orthopaedic infection.

Methods: We used a retrospective design to create a cohort of patients who received Daptomycin therapy to treat orthopaedic infections over 36 months; 2007-2010. Information on patient demographics, diagnosis, antibiotic dosing and side effects was analyzed. Myopathy was defined as a rise in creatinine kinase greater than 5 times baseline, or above our normal laboratory limit. Outcomes at 6 and 12 months after initiation of Daptomycin were defined as "Infection Controlled" (off all antibiotics, on suppressive oral antibiotics, or new infection) or "Infection Not Controlled" (recurrent infection with the same organism, or death associated with initial infection). Proportions and exact 95% confidence intervals (CI) of side effects and outcomes were computed.

Results: Daptomycin salvage therapy for orthopaedic infection was prescribed for 94 patients. Of these, 86 patients received 6 mg/kg/day and 8 patients received 4 mg/kg/day. Daptomycin was stopped due to antibiotic intolerance in 22 patients (23%, 95% CI: 15%-33%). There were 2 cases of suspected eosinophilic pneumonitis on treatment. Myopathy developed in 15 patients (16%, 95% CI: 9%-25%) and was not associated with time on treatment. At 6 month follow-up (87 patients available) 89% (95% CI: 79-94%) of patients had controlled infection, and at 12 months follow-up (60 patients available) 95% (95% CI: 86-99%) of patients had controlled infection. The rarity of Daptomycin treatment failure made statistical analysis of predisposing factors limited. However, 14/15 patients with retained hardware during therapy had their infection controlled one year later. 5/6 patients who failed therapy by 6 months were on higher dose Daptomycin. Treatment failure also appeared unrelated to infection location and organism type.

Conclusion: Daptomycin appears to be a promising salvage therapy for the treatment of orthopaedic infections. Randomized clinical trials are needed to evaluate Daptomycin use as a first line therapy

Subject Category: A. Antimicrobial agents and Resistance

Alexander DeHaan, MD1, Kimberly Felder, PA-C2, Lynn Marshall, Ph.D1, Darin Friess, MD1 and Penelope Barnes, MBBS, Ph.D1,2, (1)Orthopaedics and Rehabilitation, Oregon Health and Sciences University, Portland, OR, (2)Infectious Disease, Oregon Health Sciences University, Portland, OR


A. DeHaan, None

K. Felder, None

L. Marshall, None

D. Friess, None

P. Barnes, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.