Comparative evaluation of latex agglutination (LAT) and coagglutination (COAG) tests for rapid diagnosis of typhoid fever
Kaur, I.R.; Talwar, V.; Gupta, H.C.; Rawat, S.
Journal of Communicable Diseases 20(4): 344-348
1988
ISSN/ISBN: 0019-5138 PMID: 3268601 Document Number: 307473
Blood culture broths and serum samples from 38 clinically suspected cases of typhoid fever (Group I), 10 febrile cases other than typhoid fever (Group II) and 10 healthy controls (Group II) were studied for Salmonella typhi antigen by Latex agglutination (LAT) and Coagglutination (COAG). S. typhi was isolated by blood culture in 28 (73.7 per cent) of the Group I cases and antigen was detected by both, LAT or COAG, in 28 (92.9 per cent) of these blood culture broths. In serum of these cases antigen was detected in 75 per cent of Group I by LAT and in 14.3 per cent by COAG. 10 (26.3 per cent) of the Group I cases were culture negative but showed four fold rise in titre in Widal test, antigen was detected in all sera of these cases by LAT but only in 2 (20 per cent) by COAG, indicating that LAT was more sensitive for antigen detection than COAG. In Group II and Group III cases antigen was detected only in two sera of Group II in patients where Escherichia coli was isolated from blood. Widal test in Group II and Group III did not show rise in titre of TO or TH.