First case of urban leishmaniasis in the Campeche State, Mexico.

Cutaneous leishmaniasis represents 99% of all reported leishmaniasis cases in Mexico and typically occurs in agricultural or sylvatic areas. Campeche State is endemic for leishmaniasis; however, there are no previous records of urban Leishmania transmission. This report presents a case of cutaneous leishmaniasis in a 75-year-old man residing in an urban area. The patient presented with a three-month-old lesion on the right ear following an initial misdiagnosis of a bacterial infection. Given the suspicion of leishmaniasis, a tissue imprint was collected, revealing the presence of Leishmania amastigotes. Subsequently, amplification and sequencing of the Alanine aminotransferase and Internal transcribed spacer subunit 1 genes confirmed the presence of Leishmania mexicana. The patient was then treated with intralesional meglumine antimoniate. This case is significant as it marks the first confirmed human transmission of L. mexicana in an urban environment in Campeche State, demonstrating the importance of considering this pathology in patients with skin lesions originating from non-endemic areas in Mexico.