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.

Resumen

Introducción y objetivo

Se estudió la evolución natural de los pacientes con enfermedades crónicas que son colonizados por Staphylococcus aureus resistente a la meticilina (SARM) para determinar la persistencia de colonización al año, e identificar factores predictores de persistencia.

Material y métodos

Estudio multicéntrico, prospectivo y observacional. Se incluyeron los ingresados en un hospital y los 4 centros sociosanitarios de referencia, recogiendo datos estadísticos, clínicos y microbiológicos (muestras nasales y cutáneas), trimestralmente durante un año. Los portadores recibieron mupirocina.

Resultados

Se identificaron 114 portadores de SARM entre los 699 ingresados. Fueron portadores persistentes el 59,4% de aquellos que completaron el seguimiento. Los factores basales asociados a la persistencia fueron la insuficiencia cardíaca, las comorbilidades, la antibioterapia y las úlceras. Al año: CSS, bajo peso, índice de Barthel < 60, y úlceras (estos 2 últimos de forma independiente). Persistencia y descolonización no estuvieron estadísticamente relacionados.

Conclusión

Se detectó una elevada persistencia de SARM al año, independientemente asociada a dependencia funcional y úlceras. Esta información es útil para detectar el riesgo de ser portador de SARM desde su ingreso.