Factors for persistence of MRSA carriage one year after initial detection in individuals from various healthcare institutions

Abstract

Introduction and objective: We studied the natural history of patients with chronic stable illnesses that are colonized by Methicillin Resistant Staphylococcus aureus (MRSA). The aim was to determine the persistence colonization 1 year after. Moreover, we intended to disclose factors that predict MRSA persistence.

Material and methods: A multicentric, prospective observational study was designed. Patients from an acute-care hospital and 4 long-term healthcare facilities were included. Demographic, clinical and microbiological data (nasal and skin swabs) were obtained every 3 months during a year. MRSA carriers were decolonized with nasal mupirocin.

Results: Among the 699 screened patients, 114 MRSA carriers were identified. MRSA carriage persisted in 59.4% of those who completed the follow-up. Baseline factors associated to MRSA persistence were heart failure, comorbidities, antibiotics, and ulcers. At one year: LTHF, underweight, Barthel<60, and ulcers (the two latest were independent predictors). Persistence was not associated to decolonization.

Conclusion: Our study disclosed a high MRSA persistence rate and identified several associated factors (both at baseline and one year later). This information may be useful to identify individuals at high-risk of being MRSA carriers at hospital admission.

Keywords: Acute care hospital; Centros sociosanitarios; Colonización; Colonization; Hospital de agudos; Methicillin-resistant Staphylococcus aureus; Nursing homes; Persistence; Persistencia; Staphylococcus aureus resistente a la meticilina.