Addressing the Gaps and Challenges of Autochthonous Mucocutaneous Leishmaniasis in Spain.

Autochthonous mucocutaneous leishmaniasis caused by Leishmania infantum is an under-recognised but established manifestation of endemic leishmaniasis in Spain. This review identified 65 confirmed autochthonous cases reported since 1990, showing a relatively consistent clinical pattern. Most patients were adults, predominantly men in the fifth or sixth decade of life. Nearly half were immunosuppressed, mainly due to HIV infection, corticosteroid use, biologic therapy, autoimmune diseases, or solid organ transplantation, although immunocompetent individuals were also affected. The laryngeal, nasal, and oral mucosa were the most commonly involved sites, with occasional tracheal and bronchial disease. Clinical presentation was typically chronic and non-specific, including ulcerative, nodular, polypoid, or tumour-like lesions that frequently mimicked malignancy or inflammatory disorders, often delaying diagnosis. Unlike classical New World mucocutaneous leishmaniasis, Spanish cases generally lacked a preceding cutaneous lesion, supporting recognition as a distinct form of L. infantum infection. Diagnosis required microbiological confirmation, ideally with species identification through culture or molecular methods, while serology showed limited reliability. Treatment approaches varied considerably, reflecting the absence of standardised protocols, although systemic therapy (particularly liposomal amphotericin B) was most commonly used. Improved recognition, surveillance, and inclusion in clinical guidelines are needed to reduce diagnostic delay and therapeutic variability.