What are the common classifications of keratotic skin diseases

Keratosis is a skin disease caused by excessive keratinization of the epidermis. It often manifests as localized skin hyperplasia of keratin, causing excessive dryness of the skin and the formation of scales, which can cause skin cracking. Some patients will experience symptoms of itching and pain, especially in winter when the weather is relatively dry and the incidence rate is relatively high. Keratosis is mainly divided into ichthyosis, palmar keratosis and toad skin disease.

1. Ichthyosis

Commonly known as ichthyosis. When the production of epidermal stratum corneum increases or adhesion increases, scales may be produced. The scales are tightly attached to the surface with free edges and are arranged like fish scales, hence the name.

2. Palmoplantar keratosis

A group of inherited disorders characterized by marked keratinization of the palms and soles. The most common types are diffuse and disseminated, both of which are autosomal dominant. Diffuse palmoplantar keratoderma usually occurs in childhood and is characterized by obvious yellowish hyperkeratosis, hard texture, and smooth surface on the palms and soles of both sides. In severe cases, the disease may proliferate like warts, with cracks in winter, affecting the elbows, knees, shins and front of the ankles.

3. Toad skin disease

A cutaneous manifestation of vitamin A deficiency. When vitamin A is deficient, its ability to inhibit polyamine synthesis may be reduced, causing this disease characterized by hyperkeratosis. It is common in children and young people, and is manifested by the presence of numerous millet-sized follicular papules on the skin of the extensor sides of both upper limbs, the outer sides of both thighs, and the trunk. These papules are cone-shaped, dark red in color, hard in texture, and have a thorny keratin plug in the center. After the keratin plug is removed, a small pit is left. Generally no symptoms. It is named because the papules are densely packed and the skin looks like a toad's skin.

4. Menopausal keratosis

It occurs in postmenopausal women and manifests as hyperkeratosis and obvious thickening of the palms, soles, or both. This disease can also be seen after oophorectomy or hysterectomy. Treatment with female hormones is often ineffective.