Initially, a nodule, or abscess over months to years progresses to chronic infection with the formation of granulomatous nodules drained by sinuses connecting with the skin. Superimposed bacterial infection may result in larger open ulcers.
These changes eventually lead to deformity. The changes on imaging are remarkable with the bones being destroyed and remodeled.
Some publications have stated a "dot in a circle sign" as a characteristic MRI feature for this condition 3,4 (this feature has also been described on ultrasound ref).
History and etymology
The disease was first described in Madurai, India (in the southernmost state of Tamil Nadu) in 1842.
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- 2. Gold RH, Mirra JM. Case report 442. Madura foot (mycetoma pedis). Skeletal Radiol. 1987;16 (7): 577-80. - Pubmed citation
- 3. Cherian RS, Betty M, Manipadam MT et-al. The "dot-in-circle" sign -- a characteristic MRI finding in mycetoma foot: a report of three cases. Br J Radiol. 2009;82 (980): 662-5. doi:10.1259/bjr/62386689 - Pubmed citation
- 4. Parker L, Singh D, Biz C. The dot-in-circle sign in Madura foot. J Foot Ankle Surg. 48 (6): 690.e1-5. doi:10.1053/j.jfas.2009.07.007 - Pubmed citation
- 5. Sakayama K, Kidani T, Sugawara Y et-al. Mycetoma of foot: a rare case report and review of the literature. Foot Ankle Int. 2004;25 (10): 763-7. Foot Ankle Int (link) - Pubmed citation
- 6. Alam K, Maheshwari V, Bhargava S et-al. Histological diagnosis of madura foot (mycetoma): a must for definitive treatment. J Glob Infect Dis. 2009;1 (1): 64-7. doi:10.4103/0974-777X.52985 - Free text at pubmed - Pubmed citation