Atypical manifestations of leishmaniasis in the state of Mato Grosso: a clinical-epidemiological study at the Júlio Müller University Hospital (2013-2023).

Abstract

Background: Leishmaniasis is a neglected tropical infectious disease caused by protozoa of the Leishmania genus and transmitted by the bite of female sand flies. It may present with various clinical manifestations depending on species, parasite load, and host immunity. Recently, a geographic expansion of the disease has been observed, along with variations in clinical manifestations.

Methods: We aimed to better define this clinical entity in the Brazilian context by describing leishmaniasis cases with atypical clinical manifestations treated at the Júlio Müller University Hospital in Cuiabá, Mato Grosso, between 2013 and 2023.

Results: During the study period, 1,041 cases of cutaneous and mucosal leishmaniasis and 51 suspected cases of visceral leishmaniasis were recorded, of which 47 were classified as atypical (4.5%). Atypical presentations included localized cutaneous forms with unusual morphology (91.5%), mucocutaneous forms (4.2%), one case resembling post-kala-azar dermal leishmaniasis (2.1%), and one case of mucocutaneous lesions occurring after visceral leishmaniasis (2.1%), both of which are considered atypical in Brazil, where there is no endemic description of post-kala-azar dermal leishm aniasis. Most cases involved men aged 50-59 years, who were predominantly rural workers. These cases primarily originated from the Cerrado biome. The lesions had a median evolution of 120 d and mainly affected the lower limbs and face. Uncommon symptoms included fever, weight loss, and hepatosplenomegaly. Molecular identification of the etiological agent contributed to the diagnosis of selected cases.

Conclusions: This study highlights the importance of recognizing atypical clinical manifestations of leishmaniasis to improve disease diagnosis and management.