Comparative Analysis of Widal Test and Blood Culture for Typhoid Fever Diagnosis at a Hospital in Adamawa State, North East Nigeria

Typhoid fever diagnosis in resource-limited settings in Nigeria frequently relies on the Widal agglutination test despite its recognised limitations, while blood culture remains the gold standard but is underutilised. This study compared the diagnostic utility of the Widal test and blood culture for typhoid fever at Lamido Specialist Hospital, Jalingo, Taraba State, North East Nigeria. A cross-sectional study enrolled 200 febrile patients with clinical features suggestive of typhoid fever. Blood cultures were inoculated in BACTEC blood culture bottles and incubated for up to seven days. Subcultured isolates were identified and tested for Salmonella typhi by agglutination with specific antisera. Widal tests were performed on the same blood samples using standard tube agglutination. Blood culture was positive in 19.5% of patients. The Widal test using a titre of 1:160 as the diagnostic threshold showed sensitivity of 76.9%, specificity of 51.7%, positive predictive value of 29.4%, and negative predictive value of 89.6% against blood culture. Prior antibiotic use significantly reduced blood culture positivity without affecting Widal titres. The high rate of false-positive Widal results in endemic areas substantially limits its diagnostic value. The study recommends that blood culture should be prioritised in all suspected typhoid cases and that reliance on Widal testing alone should be discouraged in North East Nigerian clinical practice. Keywords: typhoid fever, Widal test, blood culture, Salmonella typhi, diagnostic accuracy