Porokeratoses (porokeratosis; from the Greek. poros - hole, it's time keras, keratos - horn-substance) - chronic skin disease with sharply hyperkeratosis, without subjective sensations. Some authors include porokeratoses to the nevi, others emphasize dominant hereditary nature of the disease. Histologically - main changes in the epidermis in the form mainly of hyperkeratosis, expressed more sharply on the periphery of the affected area, where there is more and thinning malpighiales network. In the dermis - papillomatosis and chronic inflammatory process. MEBELI (V. Mibelli) noted the connection of hyperkeratosis with streams of sweat glands, Respighi (that is, Respighi) - follicles, P. A. Pavlov has confirmed the possibility of development of hyperkeratosis out of touch with the sweat glands and hair, as well as hypertrophy transparent layer (hyperoliids). porokeratoses develop at any age, most men. The disease begins with the appearance miliary plotnosti knots resemblance follicular papules keratosis. As more items rash develops various sizes and shapes, shaped plaques (printing. Fig. 3 and 4) with the Central depression and peripheral roller with a groove, which is the Horny plate. Inflammation in the affected areas and around them are missing. In the Central part of plaque may be hyperkeratosis, easy peeling and atrophy. The centers often solitary. Depending on the severity of hyperkeratosis (see) they can be superficial, sometimes deeper. Color foci grayish-yellow, rarely black. Porokeratoses localized everywhere, often on the backs of the hands and feet, face and genitals. Sometimes there linear arrangement rash mainly on the limbs. Porokeratoses develops and on the mucous membrane of the oral cavity, where the clinical picture is a little distinctive and sometimes reminds red flat zoster, follicular diskeratoz Daria, lakopenicescoe changes. Lesions on the mucous membranes and the skin usually are seen at the same time, only on mucous membranes they are rare, more often on the lips and genitals. Differential diagnosis with annulare atrophic lichen planus; porokeratosis Mantoux test, follicular serpiginosum the keratosis Lucca a disease of Kyrle.
Local treatment - snow carbon dioxide, electrocoagulation, curettage, surgical removal. From the funds of the General treatment is considered to be the most effective vitamin a daily dose of 150 000 ME within 2-6 months. Cm. also Keratoses.

Fig. 3. The focus of porokeratosis on the rear right hand.
Fig. 4. Multiple foci of porokeratosis the skin of the abdomen and left hip.