A COMPARATIVE STUDY OF WIDAL TEST WITH BLOOD CULTURE IN THE DIAGNOSIS OF TYPHOID FEVER IN FEBRILE PATIENTS ATTENDING GGH, ANANTHAPURAMU.

Abstract

Introduction Typhoid fever is a systemic prolonged febrile illness caused by certain Salmonella serotypes including Salmonella typhi, S. paratyphi A, S. paratyphi B and S. paratyphi C. 1 Human beings are the only reservoir host for typhoid fever. It is transmitted is by feco-oral contamination of water and food in endemic areas especially by carriers handling food. The World Health Organization (WHO) estimates about 21 million cases of typhoid fever with >600,000 deaths annually. 2 The cases are more likely to be seen because of rapid population growth, increased urbanization, and limited safe water, limited infrastructure and health systems. Aims & Objectives The main aim of this study is to compare the result of Widal test and blood culture in the diagnosis of typhoid fever in febrile patients. Material & Methods: This is a prospective study conducted in the GGH Anantapuramu, for a period of 18 months .i.e. from May 2018 to Oct 2019. Blood samples were collected from 542 febrile patients with symptoms clinically similar to typhoid fever. Blood culture was used to isolate S.typhi and S.paratyphi. Slide agglutination test and tube agglutination tests were used for the determination of antibody titer. An antibody titer of ≥1:80 for anti TO and ≥1:160 for anti TH were taken as a cut of value to indicate recent infection of typhoid fever. Results: A total of the 542 patients were the study population, among which 384 (70.8%) were females, and 158 (29.1%) were males. Widal and blood culture was performed, 11 (2.02%) cases of S. typhi and 5 (0.9%) cases of S. paratyphi were identified using blood culture. The total prevalence of typhoid fever is 2.95%. The specificity, sensitivity, Positive Predictive Value, and Negative Predictive Value of the Widal test with O Ag is 70%, 81.25%, 10.93%, and 96%, respectively, and with H Ag is 40%, 96%, 18.1%, 98.8% respectively.