Mycetoma, a chronic granulomatous infection which extends into the subcutaneous tissue and the underlying bone, is caused by a wide variety of fungi, including Madurella mycetomatis, M. grisea and Allescheria boydii (eumycetoma), and also by certain “actinomycetes” such as Actinomadura madurae, A. pelletieri and Nocardia asteroides (actinomycetoma). The lesions, which most commonly occur on the lower leg and foot (madura foot), are characterized by painless subcutaneous nodules and the subsequent formation, over several years, of multiple granulomatous draining sinuses. If left untreated, mycetoma may ultimately result in gross deformity of the lower leg.

Treatment

Small, localized lesions are best removed surgically. Eumycetoma infections are mostly resistant to chemotherapy, but oral administration of griseofulvin, 10 mg/kg daily as a single dose for up to 4 weeks, or ketoconazole, 200-400 mg daily for up to 2 weeks, or parenteral administration of amphotericin B, 0.25-1.0 mg/kg daily by infusion for 10-14 days, can be tried. Ketoconazole is effective in about 50% of infections caused by the fungus Madurella mycetomatis. In contrast, actinomycetoma is usually responsive to dapsone or sulfonamides administered over a period of 4-6 months either alone or in combination with rifampicin or streptomycin. Sulfamethoxazole/trimethoprim in combination with streptomycin has also been used. Advanced cases may need radical surgery.