Vascular Catheter--Related Bloodstream Infection Due to Acinetobacter johnsonii (Formerly Acinetobacter calcoaceticus var. lwoffii): Report of 13 Cases

Although Acinetobacter baumannii (formerly Acinetobacter calcoaceticus var. anitratus) is known to be an important nosocomial pathogen, the clinical impact of other Acinetobacter species is not fully understood. Acinetobacter johnsonii (formerly a subset of A. calcoaceticus var. lwoffii) is considered a commensal on human skin, and infections due to this organism have not been reported previously. During a study period of 18 months, however, 13 patients at 6 hospitals developed catheter-related bloodstream infections caused by A. johnsonii. All patients had an indwelling peripheral or central venous catheter, and 11 patients were receiving a continuous intravenous infusion of heparin via the offending catheter. The clinical course of A. johnsonii bacteremia was usually benign. Infections responded readily to removal of the catheter, with or without administration of appropriate antibiotics. No insertion-site infections were documented. Thus A. johnsonii must be regarded as an organism that can cause rare cases of bloodstream infection in immunocompetent patients.