[Essential trace element and skin diseases].

We have described herein various skin diseases which are caused by essential trace element deposition, deficiency, allergy, etc. Pigmentation of hemochromatosis and hemosiderosis are recognized by hemosiderin deposition in the dermis. Acrodermatitis enteropathica is caused by a deficiency of Zn and is classified as either a hereditary type or as an acquired type. The former is autosomal recessive and the latter is caused by a low intake of Zn. Wilson's disease and Menkes' kinky hair syndrome, which are caused by abnormal Cu metabolism, elicit hyperpigmentation and morphological changes of the hair, respectively. It appears that kinky hair formation results from low activity of sulfhydryl oxidase which is a Cu enzyme. Bowen disease, which is carcinoma in situ, is caused by As toxicosis. Some cases, such as palmo-plantar-pustulosis, lichen planus and oral lichen planus are caused by allergies to metals used in dental surgery, especially Ni, Co, Cr and Sn.