Antibiogram, biotyping and plasmid profile analysis of Acinetobacter calcoaceticus var. anitratus

Antibiogram, biotyping, and plasmid profile analysis were studied on 115 isolates (40 nosocomial and 75 community strains) of Acinetobacter calcoaceticus var. anitratus isolated from clinical specimens. By disk diffusion method, we found 14 antimicrobial susceptibility patterns. Among them, the gentamicin-resistant patterns were recovered more frequently from nosocomial origin than from community-acquired origin. Fifteen patterns of biocodes were found by using GNI card of AutoMicrobic System (Vitek System). By using rapid alkaline extraction method and agarose gel electrophoresis, 102 isolates (88.7%) contained plasmids, and 72 distinct profiles were found. No particular plasmid profile correlates with specific antibiogram or biotype. However, multiple isolates with identical antibiogram and biotype recovered from the same patient were usually of identical plasmid profile. In view of the heterogeneity of the plasmid patterns that were found, the combined use of antibiogram, biotyping, and plasmid profile analysis could be satisfactory for epidemiological investigation.