title: A comparative study of Widal test with blood culture in the diagnosis of typhoid fever in febrile patients.
abstract: BACKGROUND
  Typhoid 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.
  
  
  METHODS
  Blood 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.
  
  
  RESULTS
  One 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.
  
  
  CONCLUSIONS
  Widal 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.
authors.affiliation: Department of Medical Laboratory Sciences, College of Medical Sciences, Haramaya University, Harar, Ethiopia. gandualem@yahoo.com.
authors.forename: Gizachew
authors.initials: G
authors.lastname: Andualem
authors.forename: Tamrat
authors.initials: T
authors.lastname: Abebe
authors.forename: Nigatu
authors.initials: N
authors.lastname: Kebede
authors.forename: Solomon
authors.initials: S
authors.lastname: Gebre-Selassie
authors.forename: Adane
authors.initials: A
authors.lastname: Mihret
authors.forename: Haile
authors.initials: H
authors.lastname: Alemayehu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000372:Agglutination Tests; D000907:Antibodies, Bacterial / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002648:Child; D005002:Ethiopia; D005260:Female; D006769:Hospitals, General; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012485:Salmonella typhi / Q000276:immunology* / Q000302:isolation & purification*; D014435:Typhoid Fever / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D015415:Biomarkers