Epidemiological aspects of the relationship between Infection and colonization by methicillin-resistant Staphylococcus aureus

Objectives: Examine epidemiological aspects of the relationship infection-colonization by Methicillin Resistant Staphylococcus aureus (MRSA). Methods: MRSA incident cases at Son Llatzer Hospital in Palma during 10 years (January 2003 to December 2012). Study transversal descriptive. Principal variables: clinical sample where MRSA were isolated, nares or/and cutaneous colonization, age and sex. Univariate, bivariate and multivariate statistical analyses were undertaken. Results: 691 cases were studied, 688 with clinical samples. Mean age was 68.2 years (CI95%: 66.8-69.6), 417 men (60.3%). MRSA isolated in samples from wounds 46.7% and in respiratory 30.6%. 53.5% had nares colonization and 38.4% cutaneous. At the bivariate level, wounds and respiratory samples were associated to nares colonization. Urine samples were associated to cutaneous colonization. At the multivariate level, the variables that better explained the presence of MRSA in wound samples were to be men, over 65 years old and have nares colonization. For MRSA in respiratory samples were to be men over 65 years old and nares colonization. For MRSA in urine samples, to be over 65 years old and have cutaneous colonization. Conclusions: MRSA was mainly isolated in wound and respiratory samples. Nares colonization was the most frequent.