Nosocomial Acinetobacter Baumannii Bacteremia: Comparison of the Clinical Manifestations of Multiresistant Strain and Non-multiresistant Strain Infections

The purpose of this study was to compare clinical manifestations of infections caused by the multiresistant strain of Acinetobacter baumannii with that caused by the non-multiresistant strain. A total of 23 patients with nosocomial A.. baumannii bacteremia treated between January 1, 1998 and April 30, 1999 were included in the study; 13 were infected with the multiresistant strain. The overall incidence of nosocomial A. baumannii bacteremia was 4.34 per 10,000 admissions. The male to female ratio was 1.3. The mean age of patients was 60.7 years old (range: 1-8 1). Fifteen patients belonged to the fatal and ultimately fatal group by the McCabe and Jackson criteria, and 17 patients required hospital stay in the intensive care unit. The main risk factors included catheter usage, previous antibiotic usage, and prior ventilator usage. Twenty-one patients had fever and two had shock at the onset of nosocomial A. baumannii bacteremia. Respiratory tract infection was the most common source of infection. The mortality rate of nosocomial A. baumannii bacteremia was 56.5% (13/23). When the clinical manifestations of patients infected with the multiresistant strain were compared to those of patients infected by the non-multiresistant strain of A. baumannii, no significant difference in the risk factors and clinical presentations could be discerned between these two groups. Nosocomial acquisition of the multiresistant A. baumannii strain was associated with excess mortality (76.9% vs. 30%, P=0.04). Early detection of multiresistant A. baumannii is important in making early and correct treatment. The development of a new diagnostic technique is needed to confront the problem of troublesome A. baumannii infection.