Psoriasis is a medical condition that occurs when skin cells grow too quickly. Faulty signals in the immune system cause new skin cells to form in days rather than weeks. The body does not shed these excess skin cells, so the cells pile up on the surface of the skin and lesions form.Psoriasis signs and symptoms can vary from person to person but may include one or more of the following.
- Red patches of skin covered with silvery scales
- Small scaling spots (commonly seen in children)
- Dry, cracked skin that may bleed
- Itching, burning or soreness
- Thickened, pitted or ridged nails
- Swollen and stiff joints
Psoriasis patches can range from a few spots of dandruff-like scaling to major eruptions that cover large areas.
Most types of psoriasis go through cycles, flaring for a few weeks or months, then subsiding for a time or even going into complete remission.
Several types of psoriasis exist. These include:
- Plaque psoriasis.The most common form, plaque psoriasis causes dry, raised, red skin lesions (plaques) covered with silvery scales. The plaques itch or may be painful and can occur anywhere on your body, including your genitals and the soft tissue inside your mouth. You may have just a few plaques or many.
- Nail psoriasis.Psoriasis can affect fingernails and toenails, causing pitting, abnormal nail growth and discoloration. Psoriatic nails may become loose and separate from the nail bed (onycholysis). Severe cases may cause the nail to crumble.
- Scalp psoriasis. Psoriasis on the scalp appears as red, itchy areas with silvery-white scales. The red or scaly areas often extend beyond the hairline. You may notice flakes of dead skin in your hair or on your shoulders, especially after scratching your scalp.
- Guttate psoriasis.This primarily affects young adults and children. It’s usually triggered by a bacterial infection such as strep throat. It’s marked by small, water-drop-shaped sores on your trunk, arms, legs and scalp. The sores are covered by a fine scale and aren’t as thick as typical plaques are. You may have a single outbreak that goes away on its own, or you may have repeated episodes.
- Inverse psoriasis. Mainly affecting the skin in the armpits, in the groin, under the breasts and around the genitals, inverse psoriasis causes smooth patches of red, inflamed skin. It’s worsened by friction and sweating. Fungal infections may trigger this type of psoriasis.
- Pustular psoriasis. This uncommon form of psoriasis can occur in widespread patches (generalized pustular psoriasis) or in smaller areas on your hands, feet or fingertips. It generally develops quickly, with pus-filled blisters appearing just hours after your skin becomes red and tender. The blisters may come and go frequently. Generalized pustular psoriasis can also cause fever, chills, severe itching and diarrhea.
- Erythrodermic psoriasis The least common type of psoriasis, erythrodermic psoriasis can cover your entire body with a red, peeling rash that can itch or burn intensely.
- Psoriatic arthritis. In addition to inflamed, scaly skin, psoriatic arthritis causes pitted, discolored nails and the swollen, painful joints that are typical of arthritis. Symptoms range from mild to severe, and psoriatic arthritis can affect any joint. Although the disease usually isn’t as crippling as other forms of arthritis, it can cause stiffness and progressive joint damage that in the most serious cases may lead to permanent deformity.
Vitiligo is found in almost all races in equal proportion irrespective of age and gender.