Evaluation of Salmonella typhi dipstick for detection of IgM antibodies from suspect Typhoid fever patient

Abstract

Salmonella typhi Dipstick have been developed for detection of IgM antibodies specific against S. typhi on human. In this study, we examined 195 sera from suspect typhoid fever patients with the mean of fever 10.1 ± 0.5 days by the Dipstick method and compared with blood culture. From 195 suspected typhoid fever, we found positive to Dipstick and culture were 72 samples (36.9%) and 29 samples (14.9%), respectively. On cases with fever less than 10 days, from 113 samples, the positive rate for Dipstick and culture were 51 samples (45.1%) and 21 (18.6%), respectively. From data shown above, the Dipstick method is more sensitive in detecting IgM antibodies than blood culture detection of S. typhi in day 10 after fever. Also, the positivity rate of Dipstick was significantly higher than the positivity rate of blood culture (fischer exact test, p<0.01). In conclusion, S. typhi Dipstick may be useful for detection IgM antibodies from suspected typhoid fever patients and may benefit as epidemiological tool for S. typhi infection. More study is still in progress to compare the Dipstick method nd PCR from blood and to explore the specificity of this method.