1253. A retrospective comparison of ceftriaxone versus oxacillin for osteoarticular infections due to methicillin-susceptible Staphylococcus aureus
Session: Poster Abstract Session: Staphylococcal Resistance and Epidemiology
Saturday, October 22, 2011
Room: Poster Hall B1
Background: 

Antistaphylococcal penicillins are the treatment of choice for infections due to methicillin-susceptible Staphylococcus aureus (MSSA). Another β-lactam, ceftriaxone, can be dosed once a day and is less expensive for outpatient intravenous (IV) therapy than oxacillin. Our objective was to evaluate patient outcomes using ceftriaxone vs. oxacillin for treatment of MSSA osteoarticular infections (OAI).

Methods: 

We retrospectively reviewed medical records of patients (pts) diagnosed with MSSA OAI at a tertiary care hospital from 1/2005-4/2010. We collected demographic, clinical, and outcome data including treatment-related adverse events. Successful treatment (clinical improvement; improved follow-up markers & imaging; no readmission for treatment) was compared at early follow-up (3-6 months) and late follow-up (6+ months) after completion of IV antibiotics.

Results: 

124 pts had an MSSA OAI. Median age was 53 years (range 18-85). 90 pts were diagnosed with osteomyelitis (73%) & 57 with septic arthritis (46%). 64 (52%) had orthopedic hardware involvement. 74 (60%) pts were treated with ceftriaxone & 50 (40%) with oxacillin. Median duration of IV antibiotics was 43 days (range, 22-132). Oxacillin was more often discontinued due to toxicity [11/50 (22%) oxacillin vs. 4/74 (5%) ceftriaxone; p=0.005]. Two pts were lost to follow-up at the end of IV antibiotics. At early and late follow-up, data for 97 and 88 pts were available for analysis, respectively. Treatment success was similar between groups at early follow-up [50/60 (83%) ceftriaxone vs. 32/37 (86%) oxacillin; p=0.7] and late follow-up [43/56 (77%) ceftriaxone vs. 26/32 (81%) oxacillin; p=0.6]. After IV antibiotics, 56 (45%) pts were placed on oral antibiotic suppression [31/74 (42%) vs. 25/49 (51%); p=0.3].

Conclusion: 

To our knowledge, this is the first comparison of ceftriaxone to oxacillin for MSSA osteoarticular infections with regard to patient outcomes. There was no difference in outcomes between the treatment groups at early and late follow-up visits after the completion of IV antibiotics. Pts receiving oxacillin were more likely to have it stopped due to toxicity. Additional trials are warranted to establish ceftriaxone as an equivalent treatment option.


Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Brent Wieland, MD, Jodie Marcantoni, Kyle Ota, Michael Root, David K. Warren, MD, MPH and Jonas Marschall, MD, Washington University School of Medicine, Saint Louis, MO

Disclosures:

B. Wieland, None

J. Marcantoni, None

K. Ota, None

M. Root, None

D. K. Warren, None

J. Marschall, None

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