The authors describe a case of erythrokeratodermia variabilis (Mendes da Costa type) in a three-year-old child. They present data on the clinical picture and histological examination. Major stages of the etiology and pathogenesis of the diseases are described.

A case study of the classical form of a rare form of inherited dermatosis, Mibellis disease, featuring unilateral position of the foci in a child aged 3. A histological examination revealed aggregations of parakeratotic cells in epidermis being characteristic of Mibellis disease.

The authors present a clinical and histological description of two clinical cases of a rare inherited disease, Buschke — Ollendorff syndrome. In both cases, the disease was not accompanied by the bone tissue dysplasia but at the same time it was characterized by a clear histological pattern specific of this syndrome. The authors provide literature data and discuss issues related to the pathogenesis and particular features of the clinical picture and diagnostics of the disease.