Widal reaction in Kala-azar.

Enteric fever(l) and Kala-azar (vis-ceral leishmaniasis) are endemic, in and around Patna. Kala-azar usually has an indolent course but it can present as an acute disease with fever, anorexia and vomiting(2,3). At times both the diseases are so closely similar in their presentation , that differential diagnosis is not always clear, Widal test, inspite of its limitations and fallacies is still widely used as a proof of enteric fever. We found that some of the widal positive patients did not respond to the conventional treatment for enteric fever. Later on they were proved to be cases of Kala-azar (by demonstration of Leishmania donovani bodies, in bone marrow or splenic aspiration) and responded to anti kala-azar treatment. This prompted us to take up a study to determine the behavior of Widal reaction in proven cases of Kala-azar.