IS Case 119: Mycetoma (Madura Foot)

Scott Cassar, MD

Imaging Sciences URMC 2008
Publication Date: 2009-05-20

History

A 38-year-old male, recently immigrated from Africa, presented with multiple superficial nodules and swelling.

Findings

Plain radiographs show mixed sclerotic and lytic areas within the body of the calcaneus, navicular, cuboid, cuneiforms, and proximal second metatarsal.

Diagnosis

Mycetoma (Madura Foot)

Discussion

Mycetoma is a debilitating chronic granulomatous disease in tropical and subtropical regions. The disease was first reported from the region of Madura in southern India. It may be caused by a fungal (eumycetoma) or bacterial (actinomycetoma) infection which forms small, subcutaneous swellings that enlarge and break through the skin surface, with concurrent invasion of deeper tissues. The clinical triad consists of painless soft-tissue swelling, skin sinuses, and discharge of colored grains. The infection may occur anywhere in the body, but most commonly enters the plantar surface of the foot in areas where people go barefoot.

Bone changes develop over several months. The bones typically appear moth eaten and have been classified as:

Stage 0 - Soft-tissue swelling without bone involvement
Stage I - Extrinsic pressure effects on the intact bones in the vicinity of an expanding granuloma
Stage II - Irritation of the bone surface without intraosseous invasion
Stage III - Cortical erosion and central cavitation
Stage IV - Longitudinal spreading along a single ray
Stage V - Horizontal spread along a single row
Stage VI - Multidirectional spread due to uncontrolled infection

The differential diagnosis of these radiographic features includes other types of osteomyelitis, neuropathic artheropathy, and neoplasm. Treatment for bacterial mycetoma include antibacterial agents if administered early in the course of the disease. Fungal mycetoma may respond partially to antifungal agents, however surgery is preferred if the disease is localized.

References

Abd El Bagi ME. New radiographic classification of bone involvement in pedal mycetoma. AJR Am J Roentgenol. 2003 Mar;180(3):665-8. [PMID: 12591671]
Burgener FA, Kormano M, Pudas T. Bone and Joint Disorders: Differential Diagnosis in Conventional Radiology, 2nd ed. New York: Thieme, 2006:380.
Chhem RK, Wang SC, Jaovisidha S, et al. Imaging of fungal, viral, and parasitic musculoskeletal and spinal diseases. Radiol Clin North Am 2001 Marc; 39(2):357-63. [MDConsult]