Estudo do teste rápido imunoenzimático através do antígeno recombinante rk39 para diagnóstico de leishmaniose visceral americana : correlação clínico-terapêutica

Abstract

ABSTRACT The visceral leishmaniasis diagnostic confirmation or Kala-azar is performed by detection of the parasite through direct methods of amastigotes within macrophages or monocytes, spleen aspirated, hepatic, bone marrow, lymph node histopathological and peripheral blood smear, with wide variation in sensitivity in accordance with the site searched, being the gold standard of Leishmaniasis sp . The specific antibodies for diagnostic of visceral leishmaniasis by ELISA, indirect immunofluorescence reaction and direct agglutination tests have high sensitivity and specificity cross reactions with limited by trypanosomatids and mycobacterium, including tuberculosis, leprosy, Chagas disease , leishmaniasis cutaneous and histoplasmosis. The Montenegro intradermal test is always negative during the active phase of the disease, and is based on immune memory bound on lymphocyte Th1. The purpose of this work was to highlight the importance of quick test for the detection of antibody anti-leishmania chagasi using recombinant rK39 antigen that presented sensitivity of 99.2%. There were serological by ELISA tests that presented sensitivity of 80%, and the indirect immunofluorescence reaction to Kala-azar with sensitivity of 82%. The gold-standard diagnosis made for all examinations was the direct microscopic search on parasite bone marrow aspirated and positivity was 71%, in a survey in tertiary hospitals in Fortaleza-CE. The immunoenzymatic reaction to quick test in tape containing rK39 Antigen has high sensitivity and specificity allowing immediate diagnosis and in the early beginning of treatment, in addition to confirm high-density epitopes exclusively for the Leishmaniasis genus, because there was no cross reactions among several diseases tested. We found evidence of IgG anti-leishmaniasis chagasi antibodies persistently -positive in patients treated appropriately for kala-azar, supporting with evidence that rK39 does not define disease activity and establishes criteria for cure, strengthening that other homogenizing are investigated by a positive result in individual from endemic area of Kala-azar, in disease carrier of febrile hepatosplenomegaly and pancytopenia . The quick test Rk39 must be read and interpreted immediately up to a maximum of 10 minutes driving clinical decision-making, and that its deployment as diagnostic helper method should be part of the laboratorial routine services, particularly in secondary and tertiary health endemic regions of visceral leshmaniasis . Keywords: American visceral leishmaniasis. Kala-azar. Recombinant K39 Antigen. Kala-azar through rK39 antigen diagnostic.