Acquired perforating dermatosis: Transepidermal

\s=b\A patient had acquired perforating dermatosis and suf-fered from renal disease, diabetes mellitus, and lupus vulgar-is. Histologic and immunohistochemical studies revealed that the bulk of the coarse granular basophilic material being extruded by transepidermal elimination was of nuclear origin obviously derived from polymorphonuclear leukocytes that were particularly abundant in an early, nonperforated lesion. At the lower boundary of the material being eliminated trans-epidermally, leukocytes were seen to accumulate, to under-go pyknosis and karyorrhexis, and to transform into nuclear debris. As a minor component, the material contained colla-gen fibers with altered staining qualities and, in an early lesion, elastic fibers. We speculate that accumulation, disin-tegration, and enzyme release from polymorphonuclear leu-kocytes may represent an important, hitherto disregarde