Risk Factors and Outcome Differences in Methicillin Resistant and Methicillin Sensitive Staphylococcus Aureus Septic Arthritis

Abstract

Background: Septic arthritis caused by Staphylococcus is very common and causes high mortality and economic burden. In addition, rising cases of its resistant strains (Methicillin resistant Staphylococcus Aureus) is alarming. Conflicting results in literature mandates a comparison between resistant and sensitive strains in terms of risk factors, mortality and morbidity which becomes crucial in this regard to delineate any differences in our population.

Results: We gathered 66 patients with septic arthritis, out of which 46 were men, with mean age (SD) of 51.4(18.9) years. 30 patients had MRSA and 36 had MSSA. Most patients (n=61) had one joint involved, the most common joint was the knee joint (n=31), followed by hip (n=21), ankle (n=11), shoulder (n=4) and elbow (n=2). Most patients(49) had native joints involved. The
inflammatory markers were not significantly different across the two groups. Hospital stay in both groups was almost similar(9.6 days for MRSA and 10.3 days for MSSA). Mortality3(10.0) was higher in MRSA group.

Conclusion: No differences were found in the inflammatory markers as well as synovial fluid and blood white cell count between patients infected with Methicillin resistant and sensitive Staphylococcus aureus these should not be used as a differentiating factor between the two.

Keywords: MRSA, MSSA, Septic arthritis, Risk factors.