Acinetobacter species as a cause of catheter-related infections

In recent years, Acinetobacter species have emerged as clinically important pathogens. Though these organisms are widely prevalent in nature, most human infections are hospital-acquired. Acinetobacter baumannii is the predominant species. Nosocomial Acinetobacter baumannii infections such as respiratory tract infections, urinary tract infections, meningitis following neurosurgical procedures, and bacteremia mainly affect patients with severe underlying disease in the ICU and often, in the setting of nosocomial outbreak. The occurrence of multiresistant strains often limits therapeutic options. A substantial part of Acinetobacter baumannii bacteremia cases represent catheter-related infections that usually carry a favorable prognosis. Acinetobacter species other than Acinetobacter baumannii are less frequently reported as a cause of infection in humans. Bacteremia due to these organisms is mostly sporadic and almost exclusively related to intravascular devices. The underlying diseases are often less severe than those of patients affected by Acinetobacter baumannii infections. The clinical course is usually benign and the infection responds readily to catheter removal irrespective of the appropriateness of antimicrobial therapy.