Diagnostic efficacy of Aldehyde test in late cases of Kala-azar

This case control study was carried out in the Paediatric wards of Mymensingh Medical College Hospital for a period of one year from April 2002 to March 2003 to determine the sensitivity, specificity and predictive values of Aldehyde test in the diagnosis of Kala-azar. A total of seventy five febrile cases of Kala-azar from Paediatric wards were enrolled in the study and Seventy five controls having splenomegaly with or without fever were also included from the same source. Aldehyde test was done in both cases and controls. Diagnosis of Kala-azar was confirmed by demonstration of Leish-man-Don-o-van body (LD) in bone marrow or splenic aspirates. Out of 75 parasitologically proven cases of Kala-azar, AT was positive in 56 cases. The sensitivity irrespective of duration of illness was 74.6%. We found sensitivity of AT increases with the duration of illness where AT was sensitive in 34.7% cases having fever for less than 3 months, 90.90% with fever for 3 months to less than 6 months and 100% with fever for 6 months or more in duration. Specificity of AT was calculated as 96% with positive and negative predictive values of 94.9% and 79.1% respectively. So AT is a very sensitive and specific test with high positive and negative predictive values. Considering the cost, availability, simplicity, sensitivity, and specificity we would recommend the Aldehyde test as an important diagnostic tool for field diagnosis of Kala-azar especially after three months of febrile illness.