Madura foot: Atypical MRI presentation beyond the classic dot-in-circle sign

Abstract

Madura foot is a chronic, progressive granulomatous infection caused by either fungi or bacteria. It commonly occurs in tropical and subtropical regions, particularly among individuals exposed to soil through barefoot walking. We report the case of a 20-year-old female from rural Somaliland with a two-year history of progressive swelling of the left foot associated with purulent discharge. She had previously undergone two surgical debridements, but no definitive diagnosis was established. MRI demonstrated a few classic dot-in-circle signs along with predominantly atypical bone cavities that exhibited similar signal characteristics. These lesions replaced the normal marrow of the midfoot, consistent with advanced mycetoma. The diagnosis was subsequently confirmed by histopathological examination. This case emphasizes the diagnostic value of MRI, particularly in identifying advanced and atypical features of mycetoma, while also highlighting the necessity of histopathological confirmation.