Environmental contamination because of multidrug-resistant Acinetobacter baumannii surrounding colonized or infected patients

Abstract

Multidrug-resistant (MDR) Acinetobacter baumannii (MDR-AB) is an important nosocomial pathogen associated with significant morbidity and mortality. We conducted a prospective cohort study of intensive care unit patients colonized or infected with MDR-AB at a tertiary care hospital from October 2008 to January 2009. For each patient, 10 surfaces in the patient room were sampled and evaluated for the presence of A baumannii. Pulsed-field gel electrophoresis was performed on all environmental isolates and a clinical isolate if available. Fifty rooms were sampled; 48% (24/50) were positive at 1 or more environmental sites. Supply carts (10/50, 20%), floors (8/50, 16%), infusion pumps (7/50, 14%), and ventilator touch pads (5/44, 11.4%) were most commonly contaminated. Patients with a recent history of MDR-AB were no more likely to contaminate their environment than patients with a remote history (51% vs 36%, respectively, P value = .50). In 85% (17/20) of cases, the environmental isolate was classified as genetically similar to the patient isolate. For patients with MDR-AB, the surrounding environment is frequently contaminated, even among patients with a remote history of MDR-AB. Surfaces often touched by health care workers during routine patient care are commonly contaminated and may be a source of nosocomial spread.