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Cervicofacial Actinomycetoma Presenting with Black Grain: A Rare Clinical Scenario
Shubham Lodha1, Suman Biswas1, Ayan Basu2
1Junior Resident, Department of Infectious Diseases, Institute of Post Graduate Medical Education & Research (IPGMER), Kolkata, West Bengal, India.
Abstract:
Mycetoma is a chronic skin and subcutaneous tissue infection characterized by a triad of localized swelling, draining sinuses, and grains or granules (composed of aggregations of the causative organism) within the sinus tracts. It is caused by filamentous higher bacteria (known as actinomycetoma) or fungus (known as eumycetoma). Usually actinomycetoma presents with white-yellow grains and majority of eumycetoma causes black grains. However, actinomycetoma caused by Streptomyces sp. produces large brown-black grain, which is often misdiagnosed as eumycetoma, therefore confirmation by culture is necessary. Here, we present a case of 28-year-old female presenting with typical features of mycetoma at cervicofacial region. On direct microscopy (40×) with potassium hydroxide (KOH) mount of discharge released from sinuses showed large and black grains, initially raising a suspicion of eumycetoma, but later, it was confirmed by culture as actinomycetoma caused by Streptomyces sp. Patient is now symptomatically better on treatment. Production of black grain by actinomycetoma is a rare clinical scenario.

