Bacteremia Due to Acinetobacter baumannii: Epidemiology, Clinical Findings, and Prognostic Features

Abstract

The number of nosocomial infections caused by Acinetobacter baumannii has increased in recent years. During a 12-month study, there were 1.8 episodes of A. baumannii bacteremia per 1,000 adults admitted to a hospital in Seville, Spain. Seventy-nine patients were included in the study. A. baumannii bacteremia occurred after a mean (± SD) hospitalization of 18 ± 20 days. In all cases the infections were acquired nosocomially; 71% were acquired in intensive care units. Ampicillinl sulbactam was found to be the most active agent against A. baumannii. The most common source of the bacteremia was the respiratory tract (32 cases [71%n. Twenty patients (25%) had septic shock, and 24 (30%) had disseminated intravascular coagulation (DIC). Treatment with imipenem or ampicillinlsulbactam was most effective (cure rates, 87.5% and 83%, respectively). The deaths of 27 patients (34%) were related to A. baumannii bacteremia. The presence of DIC (odds ratio [OR] = 116.4; P < .0001) and inappropriate antimicrobial treatment (OR = 15.2; P < .01) were independently associated with mortality. We conclude that most A. baumannii isolates are multiresistant and that nosocomial A. baumannii bacteremia may cause severe clinical disease that is associated with a high mortality.