Perfil clínico e desfechos de pacientes colonizados por Staphylococcus aureus resistentes à meticilina (MRSA) em um hospital terciário do Rio de Janeiro

Abstract

Introduction: Staphylococcus aureus is an important human pathogen capable of causing conditions ranging from superficial skin infections to severe invasive diseases such as bacteremia and endocarditis. The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has increased the clinical impact of this microorganism, becoming a significant public health concern associated with antimicrobial resistance. MRSA colonization constitutes an important reservoir for hospital transmission and is associated with a higher risk of subsequent invasive infections, especially among hospitalized patients with multiple comorbidities, immunosuppression, and exposure to invasive devices. Objective: To analyze the clinical profile, risk factors, and hospital outcomes of patients colonized with MRSA in a tertiary-level university hospital in Rio de Janeiro. Methods: A retrospective observational study was conducted using data from hospitalized patients between January and December 2024. A total of 162 adult patients with positive MRSA surveillance cultures were included. Clinical and demographic variables were collected from electronic medical records. Statistical analysis was performed using Excel and R software, applying Chi-square, Fisher’s exact, and Mann–Whitney tests to compare groups, considering a significance level of p < 0.05. Results: The sample (N=162) showed a predominance of females, 93/162 (57.4%), and a high prevalence6 immunosuppression 82/162 (50.6%), diabetes mellitus 66/162 (40.7%), and chronic kidney disease 26/162 (16.0%). During hospitalization, 44.4% of patients progressed to active infection and 45.1% received systemic antibiotic therapy. The overall mortality rate was 25.9%. Conclusion: MRSA colonization in the hospital setting represents an important marker of clinical vulnerability. The high frequency of infection and mortality in the cohort reinforce the need for integrated epidemiological surveillance strategies, adherence to infection prevention measures, and strengthening of antimicrobial stewardship programs.