Definition:

Psoriasis is a common chronic inflammatory skin disease marked by circumscribed dry erythematous scaly macules affecting chiefly the extensor surfaces of the body.

Aetiology:

The exact aetiology is not known. The Probable factors are disturbed fat metabolism, hormonal imbalance, septic 1ocus anywhere in the body, allergy, anxiety states, hereditary influences etc. It occurs in both sexes and all ages.

Clinical Features :

(1) Affects usually extensor surfaces of the body. (2) Dry, well defined erythematous macules, papules are present (3) A candle grease like scale can be repeatedly produced even from the non scaling lesion. (4) Complete removal of a scale produces pin..point bleeding. Itching may be slight or moderate. (5) The felon may develop along the scratch lines. This is called Kebner’s Phenomenon (6) the lesions may heal in the centre thus forming rings.

Prognosis:

In case of proper treatment the prognosis is favourable.

Warts (Verruca)

These are epidermal growths caused by filterable virus. The incubation period is 3 months, it can affects any part of the body.

Clinical types

(1) vecrruca plane—It occurs on the face and dorsum of hand usually in children nod occasionally on the face of young women. The lesions are small, smooth papule with flat tops. The papules are flesh-coloured and pin-head-sized.These are multiple— dozens in an individual.

(2) Verruca vidgaris—It occurs on the exposed parts of the body, viz, had arid feet, nails arms, legs and at times face and scalp. The lesions, single or multiple, are flesh coloured, rounded or oval papules or nodules. The size may exceed that of a pea. On the scalp the appearance may be cauliflower like.

(3) Plantar warts—It occurs mainly on the soles, on feet and occasionally palms. These are embeded in the skin lying In flask shaped cavities. The warts lie singly at pressure sites, daughter warts are round in adjoining areas. The wart appears as a painful, tender, hyperkeratotic, circular plaque with a diameter of tO- 15 mm. Pain Is felt when the wart is pressed from the sides as from the top—the pain is greatest in the morning.

(4) Condyloma aenminatum— It is a sexually transmitted hypertrophic wart occurring on the genitalia and perianal region.

Treatment:

(I) Electrocoagulation with surgical diathermy. (2) Electro cauterization under local anaesthesia.