Comparative Study on the Use of Widal Test and Stool Culture in the Laboratory Diagnosis of Salmonella Infection in Adult and Children in Jos Metropolis, Plateau State, Nigeria

Background: Salmonella infection is a common bacteria disease that causes enteric fever in humans which are shed in faeces. Presently, Widal test, Stool culture, blood culture and urine culture are the most diagnostic means of confirming salmonella infection in humans since they are based on the isolation, identification, detection and demonstration of the presence of antibodies in the serum. However, the stool and serum sample of an infected patient against the O (somatic) and H (flagella) antigents of the bacteria requires thorough laboratory analysis. This study aimed to compare the diagnostic performance of Widal test and Stool culture in the laboratory diagnosis of salmonella infection in children (0-14 yrs) and Adult (18 yrs and above). Methods: A random selection of Adult and Children with symptoms clinically suspected to be typhoid visiting the Hospital (Bingham University Teaching Hospital) at the period of the study were recruited. Informed consent of volunteers and guardians were obtained and in addition confidentially of the result was ensured. A total of 91 patients samples were tested and cultured including Adults and Children. The bacteria isolated were identified by grams reaction and biochemical characteristics. Evaluation of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of both adult and children were calculated. Results: Of the 91 patients among whom were 48 adults and 43 children. The total number of adults positive for stool culture was 12 (25 %) among which were 10 (31.2 %) males, 2 (12.5 %) females, while the total number of children positive to culture were 9 (20.9 %) among which were 7 (26.9 %) males and 2 (11.7 %) females respectively. The Widal test shows that 30 (62.5 %) were positive among which were 17 (53.1 %) males and 13 (81.2 %) females, while for children, out of 13 (30.2 %) who were positive, 8 (30.7 %) were males and 5 (29.4 %) were females respectively. Adults stool culture were found to be sensitive to Offloxacin, Ciprofloxacin, Ceffraxole and Cefuroxime while children stool culture were also found to be sensitive to Ciprofloxacin, Amoxicillin/Clavulinate, Ampicillin, Ceftazidinme and Clozacillin making them the drugs of choice. Conclusions: From the results obtained, adults were more affected than children; and the males in general were affected more than the females. The widal test therefore was found to be more sensitive while the stool culture more specific in adults and children, but salmonella infection could still occur irrespective of age or gender. Hence, Health care personnel should not totally depend on the widal test alone for the diagnosis of enteric fever, but should use other diagnostic methods to differentiate salmonella infection from other infections.