Initially a nodule, or abscess over months to years progresses to a 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).
The disease was first described in Madurai, India (in the southern most state of Tamil Nadu). Described first in 1842 in Madurai.
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