It is an immune-mediated condition that affects the skin. It causes red, flaky, crusty patches of skin covered with silvery scales. The condition is not infectious and most people are affected only in small patches on their body. Psoriasis occurs when the immune system mistakes a normal skin cell for a pathogen, and sends out faulty signals that cause overproduction of new skin cells.

Psoriasis is not contagious . It may be classified as:

Non pustular

  • Psoriasis vulgaris: It is the most common form of psoriasis. It affects 80% to 90% of people with psoriasis. Plaque psoriasis typically appears as raised areas of inflamed skin covered with silvery white scaly skin. These areas are called plaques.
  • Psoriatic erythroderma: It involves the widespread inflammation and exfoliation of the skin over most of the body surface. It is generally accompanied by severe itching, swelling and pain. This form of psoriasis can be fatal, as the extreme inflammation and exfoliation disrupt the body's ability to regulate temperature and for the skin to perform barrier functions


Pustular psoriasis appears as raised bumps that are filled with noninfectious pus (pustules). Pustular psoriasis can be localized, commonly to the hands and feet (palmoplantar pustulosis), or generalised with widespread patches occurring randomly on any part of the body. Types include:

  • Generalized pustular psoriasis (pustular psoriasis of von Zumbusch)
  • Pustulosis palmaris et plantaris (persistent palmoplantar pustulosis, pustular psoriasis of the Barber type, pustular psoriasis of the extremities)
  • Annular pustular psoriasis
  • Acrodermatitis continua
  • Impetigo herpetiformis

Other Additional types of psoriasis include

  • Drug-induced psoriasis
  • Inverse psoriasis.
  • Napkin psoriasis
  • Seborrheic-like psoriasis

Guttate psoriasis: It is characterized by numerous small, scaly, red or pink, teardrop-shaped lesions.

Nail psoriasis: It produces a variety of changes in the appearance of finger and toe nails. These changes include discoloring under the nail plate, pitting of the nails, lines going across the nails, thickening of the skin under the nail, and the loosening (onycholysis) and crumbling of the nail.

Psoriatic arthritis: It involves joint and connective tissue inflammation. Psoriatic arthritis can affect any joint, but is most common in the joints of the fingers and toes.



Plaque psoriasis
Its symptoms are dry, red skin lesions, known as plaques, that are covered in silver scales.

Guttate psoriasis:
It causes small (less than 1cm or 1/3 inch) drop-shaped sores on your chest, arms, legs and scalp


Psoriasis is an autoimmune disease, in which part of the body’s own immune system becomes overactive and attacks normal tissues in the body.


A diagnosis of psoriasis is usually based on the appearance of the skin there are no special blood tests or diagnostic procedures.

Bland emollients and moisturizers, mineral oil, and petroleum jelly may help soothe affected skin 

Bed rest

Treatment of complications (for example antibiotics, diuretics (water tablets), nutritional support)

Low-dose methotrexate, ciclosporin or acitretin

Individual cases have been reported to have successful outcomes with biologic agents, including the TNF-alpha inhibitors adalimumab, etanercept and infliximab, and ustekinumab.


  • LAST UPDATED ON : Feb 04, 2016


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