Deep mycosis mimicking cutaneous squamous cell carcinoma

Abstract

Deep cutaneous mycoses are fungal infections that affect the skin and its deeper layers, leading to significant morbidity if not promptly diagnosed and treated. While dermatophytes, particularly Trichophyton rubrum and Trichophyton mentagrophytes, are the most common causative agents, other fungi such as Candida spp., Aspergillus spp., and Fusarium spp. can also cause these infections, especially in immunocompromised individuals. The clinical presentation varies depending on the depth and extent of the infection, ranging from superficial erythematous lesions to firm subcutaneous nodules, ulcers, abscesses, or sinus tracts. In advanced cases, deep cutaneous mycoses can lead to osteomyelitis and bone destruction. Mycetoma, a chronic infectious disease affecting the skin, subcutaneous tissues, and bones, is considered a deep skin mycosis. It is endemic in certain regions and can mimic other conditions such as cutaneous tuberculosis or cancerous lesions, making accurate diagnosis challenging. Diagnosis typically involves clinical presentation, radiological findings, and microbiological culture, with molecular methods aiding in culture-negative cases. Treatment is challenging and may involve surgical debridement, antifungal/antibiotic therapy, and sometimes amputation. Prevention strategies include improving hygiene, raising awareness, and early diagnosis. We present a case of an immunocompetent farmer with a wrist lesion initially suspected as cutaneous squamous cell carcinoma but histologically diagnosed as eumycetoma, emphasizing the importance of considering deep mycoses in high-risk individuals and highlighting the heterogeneous clinical presentation of these infections.