Mucosal leishmaniasis in Brazil.

Area of Science:

• Medical Parasitology
• Infectious Diseases
• Tropical Medicine

Background:

• Mucosal leishmaniasis caused by Leishmania braziliensis braziliensis presents diagnostic difficulties.
• Accurate identification of Leishmania parasites in affected tissues is crucial for effective treatment.

Purpose of the Study:

• To compare the efficacy of an indirect immunofluorescent assay (IFA) with routine histopathology for detecting Leishmania amastigotes in mucosal biopsies.
• To evaluate treatment outcomes for mucosal leishmaniasis in endemic areas of Brazil.

Main Methods:

• Retrospective analysis of 58 patients with mucosal leishmaniasis in Bahia, Brazil.
• Biopsies were examined using hematoxylin and eosin histopathology and a genus-specific indirect immunofluorescent assay.
• Treatment efficacy was assessed based on relapse rates following low-dose (10 mg/kg) versus high-dose (20 mg/kg) meglumine antimoniate therapy.

Main Results:

• The immunofluorescent assay detected Leishmania amastigotes in 7 of 14 clinically active mucosal disease cases, while histopathology did not identify parasites in inactive cases.
• The IFA was significantly more sensitive than histopathology for detecting intracellular amastigotes in mucosal biopsy sections.
• Relapse rates were 31% for low-dose and 27.3% for high-dose meglumine antimoniate, with no statistically significant difference between the groups.

Conclusions:

• The indirect immunofluorescent assay is a superior diagnostic tool for identifying Leishmania amastigotes in mucosal biopsies compared to traditional histopathology.
• Both low and high doses of meglumine antimoniate showed similar relapse rates in treating mucosal leishmaniasis.
• Further research into optimal treatment regimens for this parasitic disease is warranted.