Genetic diversity and clonal relationships of Acinetobacter baumannii strains isolated in a neonatal ward: epidemiological investigations by allozyme, whole-cell protein and antibiotic resistance analysis.

Sixty-five strains of Acinetobacter baumannii which had been isolated from patients and the indoor environment of a neonatal intensive care unit and, for comparative purposes, isolates from three other wards, were examined by means of electrotyping and analysis of whole-cell protein and antibiotic resistance patterns. Fourteen different electrotypes were determined. The predominant type, a multiply resistant acinetobacter clone, persisted in the neonatal ward over several months. The results underline the usefulness of electrophoretic subtyping, in particular by means of allozyme pattern and as a supplement to whole-cell protein pattern analysis, in epidemiological investigations into the routes of transmission of nosocomial A. baumannii infections.