title: Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis.
abstract: BACKGROUND
  Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients.
  
  
  METHODS
  Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever.
  
  
  RESULTS
  Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection.
  
  
  CONCLUSIONS
  A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test.
authors.affiliation: Department of Family Medicine, University of Benin Teaching Hospital, Ugbowo, Benin City, Edo State, Nigeria.
authors.forename: Osahon
authors.initials: O
authors.lastname: Enabulele
authors.affiliation: Department of Community Medicine, College of Health Sciences, Delta State University, Abraka, Delta State, Nigeria.
authors.forename: Simeon Nyemike
authors.initials: SN
authors.lastname: Awunor
keywords: Co-infection; febrile illness; malaria; typhoid fever