Epidemiological investigation of nosocomial infection with multidrug-resistant Acinetobacter baumannii

BACKGROUND: Multidrug resistant Acinetobacter baumannii, (MRAB) is an important cause of hospital acquired infection. AIM: To document the emergence of MRAB in an Intensive Care Unit (ICU); and to characterize its hospital-wide outbreak by investigating antibiotypes and genotypes. MATERIALS AND METHODS: A six-month prospective study for the presence of MRAB infection or colonization on inpatients, health care workers and environmental sites was done at an ICU in Fand Hospital, Saudi Arabia. For all the collected specimens, microbiological analysis and antimicrobial susceptibility testing using an automated system (Phoenix, Becton Dick inson, USA) were performed. Pulsed-Field Gel Electrophoresis (PFGE) analysis was done to determine the clonal relationship between isolates. RESULTS: A total 18 MRAB were isolated from 12 patients and 3 environmental samples. The risk factors for the acquisition of infection were age less than 60 years, mechanical ventilation, surgical interference and co-morbidity. Five PFGE profiles; pulsotype A to E, were identified. Pulsotype C isolates were further separated into 5 subtypes with predominance of subtype C3. CONCLUSIONS: The study revealed a causal link between the contaminated ventilator and the subsequent MRAB. A correct antibiotic strategy should be addressed; and strict compliance with basic and potential control measures for the containment of infection should be achieved.