Investigating the Frequency of Staphylococcus Aureus Colonization in Intensive Care Unit Patients in Admission and during Hospitalization, Alzahra Hospital, Isfahan, Iran

Staphylococcus aureus (S. aureus) is one of the important causes of nosocomial infections in intensive care unit (ICU) patients. This study was performed to evaluate the S. aureus colonization in ICU patients in admission and the incidence of colonization during hospitalization and their associations with the relevant risk factors. From January to September 2012, a total of 164 patients were enrolled in this study. All of the patients were hospitalized for the first time in ICU of Alzahra hospital (Isfahan, Iran) and all of them were admitted more than 24 hours. Samples were collected by sterile swabs from the anterior nostrils, axillary and inguinal region. S. aureus positive samples were detected by microbiological examinations. If a patient was hospitalized more than a week in ICU and was not colonized in admission, re-sampling was done once a week. A total of 164 patients, 24(14.6%) were colonized with S. aureus in admission and 1(6.7%) was colonized with S. aureus during the ICU stay. Of these, 21(87.5%), 5(20.8%) and 2(8.3%) patients were colonized with S. aureus in anterior nostrils, axillary and inguinal regions, respectively. Compared to those without, patients with S. aureus colonization were significantly associated with surgery (P = 0.013), central venous catheter (P = 0.044) and the length of hospital stay before being transferred to the ICU (P < 0.005). The evaluation of patients for S. aureus colonization in admission is necessary especially for patients who have been hospitalized for long time. This will be effective in reducing nosocomial infections caused by S. aureus.