INTERPRETATION OF THE WIDAL TEST IN THE DIAGNOSIS OF TYPHOID-FEVER INBANGLADESHI CHILDREN

The value of a Widal test in diagnosing typhoid fever was assessed in children aged between 1 and 10 years in Bangladesh. The test was done on sera specimens from 300 healthy school children, 100 patients with non-typhoidal febrile illness and 150 bacteriologically proven cases o f typhoid fever. Salmonella typhi O and H agglutinin titres > 1:80 and > 1:160 were considered to be significant with 88% sensitivity and 98 % specificity, respectively. Among the bacteriologically proven cases, 11.3% showed no response to either agglutinin, and in another 17.3% o f cases there was no response for TO agglutinin. This study suggests t hat in children in an endemic area a positive Widal test is of conside rable importance in diagnosing typhoid fever. Furthermore, negative re sults should be interpreted with caution and both the agglutinins must be considered equally important. Reliance on somatic (TO) antigen onl y will result in missed diagnosis.