Serological Typing of Acinetobacter baumannii Species.
- Author:
Dong Taek CHO
;
Hong Tae CHA
;
Je Chul LEE
;
Jung Hoon LEE
- Publication Type:Original Article
- MeSH:
Acinetobacter baumannii*;
Acinetobacter*;
Agglutination Tests;
Bacteria;
Disease Outbreaks;
Electrophoresis;
Immune Sera;
Lactose;
Molecular Weight;
Ribotyping;
Sensitivity and Specificity;
Serotyping
- From:Journal of the Korean Society for Microbiology
1998;33(6):595-604
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
In order to evaluate the efficiency of serological typing of A. baumannii in practical application, a total of 63 strains of A. baumannii and 234 strains of Gram-negative, lactose non-fermenting bacteria were tested with polyclonal rabbit immunized sera (RIS) against heat-killed A. baumannii strains by slide agglutination tests. Six typing sera of RIS were finally obtained after the checkerboard agglutination test and reciprocal cross-absorption. Species identification of sixty-three strains of A. baumannii were confirmed by ribotyping. Forty-seven (74.6%) of the 63 strains of A. baumannii showed strong positive reaction by slide agglutination tests. Thirty-nine strains could be serotypable and thus classified into 6 distinct serovars of A. baumannii, but 8 strains were unable to classify into specific serovar. Serovar 4 was the most frequent arbitrary serovar and included 17 strains among the 39. When slide agglutination tests were performed with 50-fold diluted pooled polyclonal RIS, there was no cross-reactions except one of E. coli strain among 234 strains of various Gram-negative lactose non-fermenting. Although each profile of LPS-gel electrophoresis of A. baumannii appeared to be unrelated with serovar, the patterns of western-blot of LPS after immunostaining with homologous RIS showed serovar-specificity. Several fractions of low molecular weight LPS showed cross-reaction with antisera of other serovars. In conclusion, the sensitivity and specificity of serological identification of A. baumannii strains were 74.6% and 99.6%, respectively. This result suggests that serotyping is a useful method for the identification of A. baumannii strains as well as is the epidemiological tool to trace back the source of the nosocomial outbreaks.