Chromoblastomycosis diagnosis is often delayed in immunocompromised patients with atypical clinical manifestations

Fonsecaea pedrosoi, a pathogenic fungus within the order Chaetomycosis of the family Dematiaceae, is the primary causative agent of Chromoblastomycosis (CBM). Its clinical manifestations are diverse and lack specificity, often being confused with other skin diseases, which can easily lead to misdiagnosis or missed diagnosis. This article reports a case of a 36-year-old immunocompromised female with chronic infection caused by F. pedrosoi following minor trauma to the right knee. The patient presented with plaque-like hyperplasia, pruritus, desquamation, and suppuration of the local skin over the right knee, with persistent and refractory clinical course. The definite diagnosis was ultimately established through mycological, histopathological, and molecular biological examinations, followed by appropriate therapeutic intervention. This case indicates that chromoblastomycosis is prone to missed or delayed diagnosis due to its atypical clinical manifestations. Moreover, immunocompromised patients are more likely to experience prolonged disease course and slow recovery, highlighting the critical importance of accurate diagnosis and rational selection of treatment regimens. Combined with a literature review, it analyzes the clinical characteristics and key points in diagnosis and treatment of the disease, explores approaches to strengthen the awareness of clinical monitoring, and aims to improve the overall public health awareness of the disease.