A punch biopsy specimen from the border of an ulcer revealed a patchy infiltrate of foamy histiocytes and scattered lymphocytes in the dermis and subcutaneous fat, tending to be clustered around blood vessels. Large number of acid-fast bacilli were present in the Ziehl-Neelsen stain of the specimen. Foamy histiocytes and acid-fast bacilli were also noted in the wall of the medium-sized arteries, with narrowing of the vessel lumen. No nuclear dust was observed. Slit-skin smears showed single and clustered acid-fast bacilli.
Diffuse Painless Ulcerations. Arch Dermatol. 1999;135(8):983-b-988. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-8-dof0899