Typhoid diagnosis and associated prevailing drug resistance in Mbale city, Uganda

Abstract

Background The study aimed at determining the predictive values of Widal’s test against culture and the antimicrobial sensitivity profile of Salmonella typhi (S. typhi) isolates from patients attending private health facilities in Mbale city, Uganda. This was to provide evidence-based information to policy implementers for guideline enforcement. Methods This was a quantitative cross-sectional study in which 172 participants were recruited. Blood and stool samples collected were cultured; and to each stool sample the following tests were done; Xylose Lysine Deoxycholate (XLD), Salmonella Shigella agar (SSA), and MacConkey. Isolates suggestive for S. typhi were examined with triple sugar iron (TSI) and SIM (Sulphur, indole, and motile) and antibiotic sensitivity test (Ciprofloxacin, Imipenem, Ceftriaxone, Chloramphenicol and Augmentin for sensitivity testing) conducted with Mueller Hinton respectively. Generated data was entered in the Epidemiological information (Epi Info) software (version 7) and analyzed using the contingency table to determine the sensitivity, specificity, positive predictive value and the negative predictive value. The analysis was then presented in form of graphs and tables. Results The positive predictive value (PPV) for Widal’s test was 6.8% while the negative predictive value (NPV) was 100%. Three isolates were sensitive to Ciprofloxacin (3, 100%) and Imipenem (3, 100%), intermediate to Ceftriaxone (2, 67%) and resistant to Chloramphenicol (2, 67%) and Augmentin (2, 67%). Conclusion In comparison with culture, Widal’s test is highly sensitive (100%) with a low specificity of 76% and PPV (6.8%) and NPV (100%). It should therefore be followed up with a more specific confirmatory test. S. typhi was highly sensitive to both Ciprofloxacin and Imipenem; and resistant Chloramphenicol and Augmentin.