title: Comparative evaluation of various tests for diagnosis of concurrent malaria and typhoid Fever in a tertiary care hospital of northern India.
abstract: BACKGROUND
  Malaria and Typhoid are two major infectious diseases, still prevalent in most of the tropical countries including India. Millions of individuals residing in these endemic cases contact these diseases either concurrently or as acute infection superimposed on a chronic one.
  
  
  OBJECTIVE
  Diagnosis and comparative evaluation of various tests for diagnosis of Typhoid- Malaria co-infection in patients suffering from febrile illness.
  
  
  METHODS
  Around 800 patients of both Out Patient Department (OPD) and In Patient Department (IPD) were referred to microbiology lab for Widal test/ Typhi dot IgG/IgM and Malaria card test between July 2012- September 2012. Patients found to be suffering from co-infection were further confirmed for typhoid by blood culture. Those patients who were found sterile on blood culture were further confirmed by stool culture. Patients positive by Malaria card test (either antibody or antigen or both) were confirmed by peripheral blood smear examination for malaria parasite by both thick and thin smear examination.
  
  
  RESULTS
  68 (8.5%) patients were found to be suffering from co- infection by the above tests. Blood culture revealed 15 (22%) bacterial pathogens in the widal positive patients out of which 6(8.8%) were Salmonella Typhi and 3 (4.41%) were Salmonella Paratyphi A. Stool culture revealed 8 (11.7%) S.Typhi and 5 (7.35%) S. Paratyphi A cases. Out of 68 patients positive by Malaria card test, only 36 (52.94%) showed Malaria parasite in peripheral blood smear also. Thus the no. of confirmed cases of co-infection was found to be only 1.6%.
  
  
  CONCLUSIONS
  The interpretation of Widal test and Malaria card test, when diagnosing concurrent malaria and typhoid fever, must therefore be done with a lot of caution. Negative or positive Widal agglutination test is neither definitive nor completely informative. Similarly erroneous interpretation of Malaria card test (especially Antibody detection card test) result may lead to prolonged treatment and economic burden on patient.
authors.affiliation: Assistant Professor, Department of Microbiology, Rohilkhand Medical College and Hospital , Bareilly, India .
authors.forename: Deepika
authors.initials: D
authors.lastname: Verma
authors.affiliation: Assistant Professor, Department of Microbiology, Rohilkhand Medical College and Hospital , Bareilly, India .
authors.forename: Sachin
authors.initials: S
authors.lastname: Kishore
authors.affiliation: Professor and HOD, Department of Microbiology, Rohilkhand Medical College and Hospital , Bareilly, India .
authors.forename: M E
authors.initials: ME
authors.lastname: Siddique
keywords: Malaria card test; Peripheral blood smear examination; Typhidot; Widal test