Histopathologic and ultrastructural studies of angiokeratoma corporis diffusum in Kanzaki disease.

A novel metabolic disease, angiokeratoma corporis diffusum (Kanzaki), was the subject of an extensive histopathologic and ultrastructural study. Findings included dilated lymph and blood vessels in the upper dermis with an orthokeratortic, thickened, horny layer in well developed angiokeratoma. In the early papules, a few sporadic dyskeratotic keratinocytes were present in the epidermis with or without a thickened horny layer. Vesicular clear vacuolation was clearly observed in the cytoplasm of the secretory portion of the eccrine sweat glands, but none was observed in the vascular endothelial cells with hematoxylin-eosin staining. Using electron microscopy, lysosomal vacuolation was observed in many cell types, including eccrine sweat gland cells, vascular endothelial cells, dermal fibroblasts, dermal neural cells, lymphocytes of peripheral blood in the skin, and glomerular endothelial cells, but none was noted in the epithelial cells of the kidney. Widely dilated vacuoles were found to contain only a small amount of fuzzy filamentous material in the vascular endothelial cells, filamentous or electron-dense granular substances in fibroblasts, and electron-dense, lamellated or homogeneous structures in eccrine sweat gland cells and in neural cells. Ultracytochemical examination revealed glycoconjugates in dilated lysosomes. Characteristics of Kanzaki Disease were shown to differ from those of Fabry disease or any other lysosomal storage disease.