Ichthyosis is a heterogeneous group of diseases characterized by excessive scaling of the skin. The term “ichthyosis” comes from the Greek “ichthy” meaning “fish”. The most common hereditary forms of ichthyosis, but the occurrence of this condition secondary to other diseases is not excluded.
Clinical forms of ichthyosis
- Congenital – hereditary ichthyosis that occurs during fetal development and is found in a newborn.
- Spiny – hereditary ichthyosis, characterized by the presence of warty horny layers in the form of pointed spikes and needles.
- Lamellar (lamellar desquamation of newborns, lamellar desquamation of newborns, epidermal desquamation of newborns) is a hereditary ichthyosis characterized by the presence of a yellowish-brown film resembling collodion on the entire body from the moment of birth.
- Linear envelope (congenital migratory dyskeratosis, linear limited ichthyosis) – hereditary ichthyosiform erythroderma, characterized by annular or polycyclic areas of erythema, surrounded by slightly raised pale pink ridges with lamellar peeling; lesions tend to change shape.
- Ordinary ichthyosis develops in the first 2-3 years of a child’s life and is characterized by severe dryness of the skin, the appearance of grayish scales on the extensor surfaces of the limbs and the trunk. Skin condition improves with age, in summer and with high humidity, worsens in cold, dry weather
- Abortive ichthyosis is an easily occurring variety of ordinary ichthyosis, characterized by dryness and roughness of the skin with the presence of small bran-like scales on the extensor surfaces of the limbs and buttocks.
- White ichthyosis is distinguished by white scales
- Brilliant ichthyosis is characterized by the transparency of the scales and their localization mainly on the limbs.
- Bullous ichthyosis occurs with the formation of blisters
- Serpentine (scutular) ichthyosis is manifested by the presence of thick scales of a dirty gray color, tightly adjacent to each other like shields (reminiscent of snake skin)
- Lichenoid ichthyosis is characterized by small scattered lesions resembling lichen
- Simple (pityriasis, pityriasiform) ichthyosis is characterized by the formation of small (up to 0.5 cm) grayish scales attached to the skin only in its central part.
- Horny ichthyosis is characterized by the formation of dense horny scales that protrude sharply above the surface of the skin.
- Black ichthyosis is distinguished by brownish-black scales that fit tightly on the skin.
- Unilateral ichthyosis (Rossman unilateral ichthyosiform erythroderma) – ichthyosis, in which the lesions are localized on one half of the body; as a rule, it is combined with multiple bone deformities and cystic lesions of the kidneys.
- Fetal ichthyosis (universal congenital hyperkeratosis, malignant keratoma, Harlequin fetus) is a form of congenital ichthyosis incompatible with life, characterized by the formation of a thick shell of numerous scales with deep cracks over the entire plane of the skin; traditionally combined with underdevelopment of internal organs.
- Follicular ichthyosis (see Darier’s disease in the article Various diseases).
- X-linked ichthyosis develops, as a rule, due to insufficiency of placental steroid sulfatase. Unlike traditional ichthyosis, X-linked ichthyosis can exist from birth. A complete clinical picture is observed only in boys. The scales are larger than with ordinary ichthyosis, brownish in color. The lesion is more extensive, skin folds, neck, rear of the foot, flexion planes of the limbs, to a lesser extent the back, and the scalp may be involved in the process. More intensively than with ordinary ichthyosis, the stomach is affected. The skin of the palms and soles is not affected, there is no follicular hyperkeratosis. Often observed clouding of the cornea, hypogonadism, cryptorchidism. All kinds of malformations (microcephaly, pyloric stenosis, skeletal anomalies), mental retardation can be observed.
The main symptoms of ichthyosis
The appearance on the skin of scales resembling fish scales. Keratinization is expressed in varying degrees – from a barely noticeable roughness of the skin to the most severe changes in the epidermis, sometimes incompatible with life. There are many forms of ichthyosis and a number of rare syndromes that include ichthyosis as one of the symptoms.
Treatment of ichthyosis
The course of acquired ichthyosis is traditionally facilitated by the treatment of the underlying disease. The therapy of congenital ichthyosis is difficult, especially its severe forms.
Hydration of the stratum corneum of the epidermis. The softness of the stratum corneum of the epidermis depends on its water content. Baths are taken to moisturize the skin, after which they lubricate the skin with petroleum jelly. Urea creams also contribute to the retention of water in the stratum corneum.
Keratolytic agents. Products containing propylene glycol, glycerin and lactic acid are effective; they are used without occlusive dressings. A product containing salicylic acid (6%), propylene glycol (60%) and ethanol (20%), which is used with an occlusive dressing, helps well. Lactic and glycolic acids reduce flaking. Products containing urea (2-20%) are effective, some of them contain lactic acid.