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What is Xeroderma and explain in detail?
Xeroderma, xerosis or xerosis cutis, or simply dry skin, is a skin condition characterized by excessively dry skin.The medical term xeroderma, meaning "dry skin", derives from modern Latin, xero- dry + Greek derma skin.
In most cases, dry skin can safely be treated with emollients or moisturizers. Xeroderma occurs most commonly on the scalp, lower legs, arms, hands, the knuckles, the sides of the abdomen, and thighs. Symptoms most associated with xeroderma are such skin conditions as scaling (the visible peeling of the outer skin layer), itching, and skin fissures (cracked skin).

Causes
Xeroderma is a very common condition. It happens more often in the winter when the cold air outside and the hot air inside creates a low relative humidity. This causes the skin to lose moisture and it may crack and peel. Bathing or hand washing too frequently, especially if one is using harsh soaps, can contribute to xeroderma. Xeroderma can be caused by a deficiency of vitamin A, vitamin D, zinc, systemic illness, severe sunburn, or some medication