Vulva Psoriasis

Psoriasis

A common, hereditary, papulosquamous disease of the skin characterized by well-defined, reddish papules and plaques with adherent silvery white scale. 2% of the population is affected. When it is found in body folds, it is referred to as inverse or flexural psoriasis.

Pathophysiology: Psoriasis appears to be due to a defective or altered immune response in a genetically predisposed individual that results in an inflammatory mechanism that induces epidermal proliferation and sustains inflammation. It can be triggered by physical trauma (like rubbing), chemical irritants, and infections and can be worsened by some drugs, for example beta-blockers and anti-malarials.

Clinically there is a variable degree of itching and irritation, worse with heat and humidity and topical irritants. Scaly pink to red patches or plaques may be seen through the hairy areas but the vulva usually shows pink lesions and not much white scaling as the area is moist. In the folds there is bilateral symmetrical surface involvement in the inguinal, labiocrural, and gluteal cleft creases. There may be maceration and fissuring. Secondary Candida can cause satellite pustules. Secondary bacterial infection gives a glossy sheen to the infected area.

Diagnosis: This is a clinical diagnosis. Look for typical psoriatic plaques in scalp, elbows and knees to support the diagnosis. Nails may be involved. Biopsy is seldom necessary. Treatment: Stop all irritant exposure. Control infection, both bacterial and Candida. Restore the epithelial barrier function with Sitz baths. Mild or mid potency topical steroid such as desonide 0.05% ointment or triamcinolone 0.1% ointment twice a day for 1-2 weeks, then alternate with calcipotriene ointment (Dovonex).