Advances in the Diagnosis of Visceral Leishmaniasis

Copyright: © 2013 Prajapati VK, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited Visceral Leishmaniasis (VL or Kala azar) is a disease of poor and neglected populations; it affects 79 countries of the world and accounts 58, 000 new cases to each year [1]. Indian subcontinent covers 90% VL cases of the world, among which Bihar state accounts for most cases [2]. In absence of antileishmanial vaccines early and accurate diagnosis holds the key for the control of VL. Till date parasitological method remains the gold standard for diagnosing VL. Microscopic demonstration of amastigotes in splenic aspirates, peripheral blood mononuclear cells and buffy coat has been shown to possess high sensitivities and absolute specificity [3,4]. Serology based diagnostic methods to detect antibodies against different recombinant Leishmania antigens (rK39, rK28, rK16) are also routinely employed to detect active cases in the field conditions. Out of these rK39 immunochromatographic test (ICT) remains the test of choice for clinicians because of its 100% sensitivity in VL subjects and 85-100% specificity in endemic healthy controls [5]. Recently recombinant antigen rK16, 39-amino acid protein obtained from C terminus of L. donovani immobilized in two different formats, a flow through test (KEFT) or Signal KA, and a lateral flow test (KELF) or Crystal KA had shown higher (sensitivity 93-99% and 99.5% respectively) in Indian subcontinent than East Africa and Brazilian VL subjects [6,7].