How Kala-azar is Diagnosed?

• Clinical:
  • A case of fever of more than 2 weeks duration not responding to antimalarials and antibiotics. Clinical laboratory findings may include anaemia, progressive leucopenia thrombocytopenia and hypergammaglobulinemia

• Laboratory: 
  • Serology tests: Variety of tests are available for diagnosis of Kala-azar. The most commonly used tests based on relative sensitivity; specificity and operationally feasibility include Direct Agglutination Test (DAT), rk39 dipstick and ELISA. However all these tests detect IgG antibodies that are relatively long lasting. Aldehyde Test is commonly used but it is a non-specific test. IgM detecting tests are under development and not available for field use.
  • Parasite demonstration in bone marrow/spleen/lymphnode aspiration or in culture medium is the confirmatory diagnosis. However, sensitivity varies with the organ selected for aspiration. Though spleen aspiration has the highest sensitivity and specificity (considered gold standard) but a skilled professional with appropriate precaustions can perform it only at a good hospital facility.

• Differential Diagnosis:

• Typhoid

•  Miliary tuberculosis

• Malaria  

• Brucellosis

• Amoebic liver abscess 

• Infectious mononucleosis

• Lymphoma, Leukemia

• Tropical splenomegaly

• Portal hypertension