Padronization of molecular techniques for routine diagnosis of visceral leishmaniasis and determination of polymorphisms in genes that encode MBL and LPL proteins in patients with LV from the Public Health Laboratory of Bauru-SP

Abstract

Leishmaniasis refers to a spectrum of infections caused by parasitic protozoa of the genus Leishmania. This disease is considered a serious public health problem. Nowadays, Brazil confronts the expansion and urbanization of visceral leishmaniasis (LV), with human cases and large number of positive dogs to canine visceral leishmaniasis (LVC) in big and medium cities. In this project we will highlight the Bauru city, which even with prophylactic attitudes, is a endemic city and has been facing significant increases in numbers of LV cases and deaths. The clinical diagnosis in humans such as dogs is complex because leishmaniasis may show signs and symptoms that are common to others diseases present in areas where LV is present. Strategies to control the disease in man are based on early diagnosis and treatment, control of vectors and serological screening with subsequent euthanasia of positive dogs for leishmaniasis. In untreated patients, the disease progresses and can achieve high levels of mortality (90%) with increased susceptibility to secondary infections. Some routine methods are used to diagnose this disease (e.g. visualization of amastigotes forms of Leishmania sp in smears of aspirates from spleen, bone marrow and lymph nodes, immune enzymatic assay (ELISA), indirect immunofluorescence assay), however none of them presents high sensitivity and specificity, in addition, these serologic tests can have false-negative results and cross reactions with other trypanosomatids. Given these limitations, it appears necessary to develop tools that are able to promote an accurate and precise diagnosis, such as molecular methods (polymerase chain reaction (PCR) and real-time PCR (qPCR). The use of these molecular techniques, routinely and on a large scale in Central Public Health Laboratories, is of fundamental importance as it contributes to the rapid diagnosis is essential for treatment and for taking practical steps and substantiated by competent health authorities in control LV. It is noteworthy that early diagnosis and rapid treatment are important to the person and community. It is known that polymorphisms in genes encoding proteins mannose-binding lectin (MBL) and lipoprotein lipase (LPL) are associated with pathogen infection and progression of various diseases, such as LV, and that its genotypes may be employed for predicting the risk of developing visceral leishmaniasis and complications. Thus, the main objective of this project is to standardize the PCR and qPCR reactions in a large scale for use in Public Health Laboratory of Bauru-SP and evaluating the genotypes found for genes encoding proteins MBL and LPL in subjects with confirmed diagnosis for LV. The control prospects and improvement in disease treatment are dependent on progress in research to give better alternatives and strategies for management of the cases. (AU)