Leprosy: type 1 leprosy reaction

Borderline tuberculoid (BT) leprosy: type 1 leprosy reaction This is a low power view of the deep dermis from a case of BT in reaction. The slide shows severe necrosis of the deep nerve, which passes horizontally at the dermal-subcutis junction (at the bottom of the section). H&E stain. This necrosis is a feature of a type 1 reaction. See image W0043347 for a higher power view of the nerve.