Analise histopatológica e imunohistoquímica da linfadenopatia em pacientes com Leishmaniose tegumentar americana no estado do Ceará, Brasil

Abstract

Lymphadenopathy has been considered an important clinical manifestation of human cutaneous leishmaniasis due to Leishmanaia (Viannia) braziliensis in Ceara State-Brazil. We carried out the histopathological and immunohistochemical analysis of 26 lymph nodes from 11 confirmed human cases of cutaneous leishmaniasis aiming to better characterize and clarify the pathogenesis ofamerican cutaneous leishmaniasis. An intense chronic lymphadenite made up the baseground feature of leishmaniasis lymphadenopathy (p=0,001), which has showed up in 96 per cent of the cases. This lymphadenite was predominantly granulomatous (92%) and used to be associated to sinusoidal histiocytosis (96%) and paracortical hypeqilasia (96%). There has still been noticed a role played by apoptosis and necrosis in, respectively, 88 and 53 per cent of the lymphadenite cases. T CD4+ lymphocytes were positively associated with the fi-equence of T memory cells (p=0,002) and macrophage (p=0,001); cells expressing TNFa were more frequently I, (^ c '• <- ' /' increased at long-lasting lymphadenitis. Cutaneous leishmaniasis with concurrent regional lymphadenite showed to be analogous to the immunopathology of the primary complex of tuberculosis and as a lymph node reaction it plays an important part in the mechanism that controls cutaneous leishmaniasis; patients who develop lymphadenopathy present a more effective immune reaction with spontaneous lymphadenite resolution in 80 per cent of the cases