Molecular, cytological, and immunocytochemical study and kDNA sequencing of laryngeal Leishmania infantum infection

Abstract

Mucosal leishmaniasis is a well-known clinical manifestation of infections mainly caused by New World Leishmania species, especially Leishmania braziliensis (Viannia) in Central and South America. It is extremely uncommon in the world, even in the endemic areas such as Fars Province, Southern Iran. Two male immunocompetent subjects who developed Leishmania mucosal lesion mimicking a laryngeal tumor presented with a several-months history of dysphonia, dyspnea, hoarseness, and odynophagia. Multiple smears from the lesions showed structures resembling the amastigote form of Leishmania. Nested PCR analysis to amplifying a fragment of Leishmania infantum kinetoplastid DNA from the Giemsa-stained smear resulted in a fragment of 680 bp. Sequence analysis of one of the strains showed 98% similarity to L. infantum strain IranJWinf (GenBank accession no. AB678348.1) and 96% similarity to L. infantum isolate MCAN/ES/98/10445 (GenBank accession no. EU437407.1), while another strain showed 97% similarity with two L. infantum strains from kala-azar patient (GenBank accession nos. AJ223725.1 and AF027577.1). Immunocytochemical staining with anti-L. infantum mAb (D2) was positive. Primary mucosal leishmaniasis (ML) may occur in the immunocompetent patients who reside in or travel to endemic areas of leishmaniasis. Mucosal leishmaniasis contracted in endemic areas, such as Iran, has to be considered in the differential diagnosis of lesions in the other mucosa and may occur in previously healthy persons. Therefore, cytology, PCR, and immunocytochemistry-based methods with anti-Leishmania mAb are helpful in the diagnosis of ML.