EC Microbiology

Introduction and Aim: Methicillin-resistant Staphylococcus aureus (MRSA) carriage represents a major concern in hospital settings, particularly in orthopedic trauma, where it may contribute to surgical site infections. In patients hospitalized for open fractures, this risk is increased due to skin barrier disruption, initial contamination, and the frequent need for surgical management. The aim of this study was to assess the prevalence of MRSA carriage among patients admitted for open fractures at Mohammed VI University Hospital in Marrakech.

Materials and Methods: This was a prospective cross-sectional study conducted over six months, from February to July 2025, including patients admitted for open fractures. Nasal and skin swabs were collected from each patient. Samples were cultured on Chapman agar. Bacterial identification was performed using conventional methods, and methicillin resistance was assessed using a 30 µg cefoxitin disk. A complete antibiogram was performed for MRSA strains according to CASFM recommendations.

Results: A total of 103 patients were included. The mean age was 46.65 years, with a female-to-male ratio of 0.73. The prevalence of nasal carriage of Staphylococcus aureus was 20% (n = 21), with all strains being methicillin-sensitive. The prevalence of cutaneous MRSA carriage was 3% (n = 3). Seventy-one percent of patients had grade II leg fractures according to the Cauchoix and Duparc classification. All MRSA carriers had a history of hospitalization and antibiotic therapy, and 67% had long-standing diabetes (>10 years).

Conclusion: The prevalence of cutaneous MRSA carriage in this series was low. However, the presence of identifiable risk factors supports the need for targeted surveillance, reinforcement of hygiene measures, and consideration of screening and decolonization strategies in high-risk patients prior to orthopedic surgery [2,6,7].

Keywords: MRSA; Open Fracture; Nasal Carriage; Skin Carriage; Orthopedic Trauma; Surgical Site Infection

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