A comparative study of Widal test with blood culture in the diagnosis of typhoid fever in febrile patients

Abstract

BackgroundTyphoid fever is a major health problem in developing countries and its diagnosis on clinical ground is difficult. Diagnosis in developing countries including Ethiopia is mostly done by Widal test. However, the value of the test has been debated. Hence, evaluating the result of this test is necessary for correct interpretation of the result. The main aim of this study was to compare the result of Widal test and blood culture in the diagnosis of typhoid fever in febrile patients.MethodsBlood samples were collected from 270 febrile patients with symptoms clinically similar to typhoid fever and visiting St. Paul’s General Specialized Hospitals from mid December 2010 to March 2011. 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.ResultsOne hundred and eighty six (68.9%) participants were females and eighty four (31.1%) were males. 7 (2.6%) cases of S. typhi and 4 (1.5%) cases of S. paratyphi were identified with the total prevalence of typhoid fever 4.1%. The total number of patients who have indicative of recent infection by either of O and H antigens Widal test is 88 (32.6%). The sensitivity, specificity, Positive predictive Value and Negative predictive Value of Widal test were 71.4%, 68.44%, 5.7% and 98.9% respectively.ConclusionsWidal test has a low sensitivity, specificity and PPV, but it has good NPV which indicates that negative Widal test result have a good indication for the absence of the disease.

Comparative study of Widal test against stool culture for typhoid fever suspected cases in southern Ethiopia

“…This high positive result in Widal slide agglutination test may be associated with cross-reacting antibodies from serum of febrile patients other than typhoid fever. Low proportion of Widal test was observed in studies conducted in Ethiopia (32.6%) 24 and Nigeria (55%), 25 as compared with the current finding. This difference might be due to difference in sociodemographic status, immune status, and antibody that cross-reacts with S. enterica serotype Typhi during infection.…”

Diagnostic Value of Widal Test in the Diagnosis of Typhoid Fever: A Systematic Review

“…Reports by the World Health Organization revealed that about 21 million cases and >600,000 annual deaths from typhoid fever occur throughout the world. Developing nations share the highest burden due to rapid population growth, increased urbanization, and limited safe water and health systems [2,3].…”

Clinically detected Enteric Fever in Children – Blood Culture as a Diagnostic Aid

“…The same study, using Widal test, also showed that TO antigen was positive (>1/80 dilution) in 47% of febrile patients, and TH antigen was positive in 26% cases (cutoff > 1/160). Positive for both TO and TH were 24.4% 5 . In a similar study, among the total of 67 adult patients clinically marked for typhoid fever, S.typhi was detected in only 8 (11.9%) patients and S.paratyphi A was detected in only 3 (4.5%) patients.…”

“…Taking diagnosis into concern, enteric fever raises confusion among the Afro-Asian countries. Blood culture technique is the most reliable diagnostic method, but is time consuming and expensive 5 . Detection of the pathogen in blood samples through polymerase chain reaction is probably the best and most reliable method.…”