[Histologic and electron microscopical investigations in a patient with benign verrucosis generalisata (author's transl)].

A report is given on a 43-year-old man who has been suffering from pointed condylomata in the region of scrotum and anus since 1975. Repeated relapses. Since 1977 verrucous lesions spreading from thorax to both arms and the throat. Histologic examination revealed intraepidermal foci of balloon cells in the stratum spinosum and stratum granulosum, partly with intranuclear basophilic inclusions. Electron microscopy showed an intact basal lamina and also partly intact epidermis. Only in the focal area the epidermopoiesis is disturbed already from the basal layer, with vacuolated destruction of the basal keratinocytes and condensation of the cytoplasm, as well as formation of myelin figures. This degenerative process together with enlarged intercellular spaces and partly conserved desmosomes continues into the stratum granulosum. From the upper stratum spinosum balloon cells characteristic for warts are found. In the stratum granulosum there are abundant atypic keratohyalin granules, and in the stratum granulosum and stratum corneum characteristic virus-containing kerationcytes are found. Furthermore, there are lots of released virus elementary bodies deposited in bizarre shapes at the horny lamellae: crystalloid or garland-, chain-, letter-, or wreath-shaped.