Leishmania (Leishmania) infantum rarely causes mucosal localized leishmaniasis, typically in the absence of concomitant visceral or cutaneous disease. Relapses up to 1 year after therapy have been reported.1 Since Leishmania parasites replicate exclusively in macrophages, they are in an excellent position to influence lymphocyte responses.
A 71-year-old Sicilian man with a history of thymectomy for thymoma 6 years previously was admitted to our hospital in January 2001 with swelling of his lateral tongue. Mucosal leishmaniasis due to L infantum was diagnosed histologically and confirmed by polymerase chain reaction.2 No signs of visceral involvement (ie, no fever or enlargment of the liver or spleen) were noted. There was no underlying disease and a test for human immunodeficiency virus proved negative. He received a 30-day course of intramuscular meglumine antimoniate with clinical response. At a follow-up visit 6 months later, no residual lesions were seen.
Mehlig A, Arnold A, Spicher T, Koch G, Hatz C, Laifer G. Late Relapse of Mucosal Leishmaniasis of the Tongue in a Patient After Thymectomy. Arch Dermatol. 2006;142(6):781-798. doi:10.1001/archderm.142.6.785