Two siblings with epidermodysplasia verruciformis with large clear cells in the epidermis: electron microscope and immunological findings.

In two Arab brothers presenting the characteristic clinical picture of epidermodysplasia verruciformis (EV), histological examination revealed large clear cells in the granular layer and uppermost part of the prickle cell layer of the epidermis. The report of this histological picture in two cases by other authors in the past had aroused considerable discussion as to the true diagnosis. The finding of large clear cells in our two confirmed cases of EV supports the opinion that this does not necessarily contradict the diagnosis of EV. Electron microscope investigation revealed groups of particles in the nuclei of a few keratinocytes in the granular layer which were compatible with papova virus particles. The changes seen in the clear cells support the theory of the viral etiology of EV. Ehe immunological studies showed intact humoral immunity but impaired cellular immunity.