Chromoblastomycosis in Peru: a retrospective review of 13 cases

Background: Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by dematiaceous fungi that mainly affects rural workers in tropical and subtropical regions. The disease poses a treatment challenge due to its refractory nature and high relapse rate. To date, few cases have been reported in Peru. Methods: We retrospectively reviewed epidemiological, clinical, microbiological, and treatment data from CBM cases diagnosed between 2011 and 2024 at the Clinical Mycology Unit of the Instituto de Medicina Tropical Alexander von Humboldt (IMTAvH) in Lima, Peru. Diagnosis was confirmed by the identification of muriform cells either on direct microscopic examination or histopathology. Results: Of the 15 identified cases, 13 had sufficient data for inclusion. In summary, 84% of the patients were men, 77% acquired the disease in the Peruvian Amazon jungle (predominantly in Ucayali and San Martin), the median age was 65.3 years (range: 33–85), and the average disease duration was 10.7 years (range: 1–25 years). The lower extremities were most frequently affected (53%), followed by the upper extremities (38%). Plaque-like and verrucous lesions were the most common (38% each), whereas tumoral and cicatricial forms were less frequent (15% each). The aetiological agent was identified by morphology in nine patients. Fonsecaea sp. was the most frequently identified pathogen (46%), followed by Cladophialophora sp. (15%) and Phialophora sp. (7%). Nine patients (69%) received oral itraconazole (200–400 mg/day) combined with cryosurgery; two (15%) received itraconazole alone; and two (15%) received itraconazole combined with terbinafine (500 mg/day). Treatment duration ranged from 5 to 136 months, with six patients (46%) achieving a cure. Conclusions: CBM in Peru is likely underdiagnosed and underestimated due to low disease recognition, limited diagnostics in remote areas, and lack of mandatory reporting.