An acute zinc deficiency state developed in 6 patients on total parenteral alimentation, which allegedly included zinc 37 mumol/l. The actual concentration of this trace element when measured by us, was 3 mumol/l. The clinical picture consisted of an acrodermatitis enteropathica-like syndrome, with subsequent development of distinctive nail lesions, which consisted of white transverse bands in all finger- and toenails. Histopathological examination of several of these cutaneous lesions revealed distinctive changes, which we consider rather specific of zinc deficiency states. They consisted in parakeratosis, cleavage and detachment of the superficial layers of the epidermis, mainly intracellular and also extracellular edema of the epidermal cells, development of microvesicles at different epidermal levels, and severe vacuolar alteration of the dermoepidermal junction. These changes also affected the outer root sheath of the hair follicles.