Mycetoma is a chronic granulomatous subcutaneous infection caused by fungi (eumycetoma) or bacteria (actinomycetoma). The classic triad includes a mass, sinus tracts, and discharge containing granules. We present an atypical case of actinomycotic mycetoma of the hand without sinus formation. An 85-year-old male farmer presented with an 8-year history of a progressively enlarging, painful mass on his left hand; he recalled that the initial lesion began as a painless pustule on the palm approximately 9 years earlier. Prior surgeries and short-course antibiotics failed. Examination revealed an indurated, erythematous mass with restricted motion but no draining sinuses. Computed tomography showed soft tissue swelling and bone erosion. Histopathology revealed yellow granules with filamentous bacteria, and the diagnosis was confirmed by RT-PCR using pan-actinomycetes primers. The patient was started on combination therapy with penicillin V and trimethoprim-sulfamethoxazole. This case underscores that mycetoma can present without classic sinus tracts, leading to diagnostic delay. A high index of suspicion and the use of histopathological and molecular methods are essential for diagnosis. Prolonged, targeted antibiotic therapy is the cornerstone of management, though advanced disease may result in a slower response.
Mirhosseyni et al. (2026) studied this question.