Mycetoma caused by a new red grain mycetoma agent in two members of a family.

An 18-year-old woman from rural West Bengal was affected with mycetoma involving her neck, back, and chest. After an interval of eight years, her younger brother developed mycetoma on his left arm. No history of trauma or immune deficiency was present in either case. By microscopic examination of sinus-discharged materials from both the cases, identical rusty red, hard grains were demonstrated. Soluble red pigment-producing colonies grew in Sabouraud dextrose-agar medium. Isolates were positive for casein hydrolysis and negative for hydrolysis test of xanthine, hypoxanthine, tyrosine, and nitrate reduction. Thus it differed from the only known red grain mycetoma agent, Actinomadura pelletieri and was provisionally identified as Actinomadura vinacea. Familial affection in mycetoma, that too caused by a new agent, is reported here for its uniqueness.