Diseases of the skin appear mainly on the skin itself, but they can also affect hair, nails, sebaceous, and sweat glands. Who gets a skin disease depends on different factors. The most common skin disease is acne, which mainly affects people in adolescence. Other widespread skin diseases include shingles, psoriasis, neurodermatitis and athlete’s foot. The typical signs of a skin disease may include wheals, papules, nodules, pustules or vesicles. They can occur singly or in patches. The skin diseases are often accompanied by severe itching.