Approaches to the control of multidrug-resistant (MDR) Acinetobacter baumannii

Abstract

ISSUE: The emergence of MDR <i>Acinetobacter baumannii</i> in a metropolitan teaching hospital as an infection control (IC) problem beginning in 2000 and the efforts to reduce the incidence in our institution. PROJECT: In early March 2000, an increased incidence of MDR <i>Acinetobacter baumannii</i> in the surgical intensive care unit was noted in the process of focused surveillance in the unit. Retrospective microbiological culture results review indicated that this microorganism represented only 7 of 38 single patient clinical isolates (SPCI) (18%) in 1999. By the end of 2000, the incidence had doubled to 37% (28 of 75). Despite intensive infection control (IC) efforts to control the spread within the institution, the incidence rose in 2001 to 53 of 82 SPCI (65%) to represent the predominant strains within the strains cultured. Pulsed-field gel electrophoresis (PFGE) showed two endemic strains as well as confirming the importation of other strains in patients transferred to our institution from other hospitals. IC interventions included education of various disciplines of healthcare workers (including nursing, physicians, medical students, respiratory and radiology staff); and cultures of the environment (sinks in the patient rooms, computer keyboards, telephones, and supply cabinets). Each IC surveillance report included either the presence or absence of MDR <i>Acinetobacter baumannii</i> in the unit report. The IC medical director also reported the incidence biannually to the medical staff executive committee. These efforts continued through 2004. RESULTS: The incidence of MDR <i>Acinetobacter baumannii</i> showed a slight decrease in 2002 to 51% (45 of 89). In 2003, the incidence decreased further to 31% (22 of 72). In 2004, there was an increase to 46% (31 of 68), however 11 of the 31 (35.5%) were community-associated. LESSONS LEARNED: Continued vigilance for the presence of MDR <i>Acinetobacter baumannii</i> is necessary to control nosocomial transmission of this microorganism. Empiric initiation of contact precautions for patients with any Acinetobacter clinical isolate until susceptibilities are completed, emphasis on the importance of hand hygiene to prevent nosocomial transmission, and feedback of results both at the unit level as well as to the executive leadership is important to control this microorganism.