Auspitz sign is seen in: March 2007, September 2010

Ans. A: Psoriasis Psoriasis involves hyperproliferation of the keratinocytes in the epidermis. Psoriasis is associated with ceain human leukocyte antigen (HLA) alleles, paicularly human leukocyte antigen Cw6 (HLA-Cw6). Clinical findings: The skin almost always is affected before the eyes. Ocular findings occur in approximately 10% of the patients. The nonocular symptoms are related to rash and psoriatic ahritis: - Psoriatic ahritis can cause stiffness, pain, throbbing, swelling, or tenderness of the joints. - The distal joints, such as the fingers, toes, wrists, knees, and ankles, are affected most often. The most common ocular symptoms are redness and tearing due to conjunctivitis or blepharitis. Corneal involvement -The most common finding is punctate keratitis. Uvea: Usually, anterior uveitis can be seen in association with psoriatic ahritis. The most common skin manifestations are scaling erythematous macules, papules, and plaques. The most common type of psoriasis is chronic stationary psoriasis (psoriasis vulgaris). This involves the scalp, extensor surfaces, genitals, umbilicus, and lumbosacral and retroauricular regions. Psoriasis inversa: It involves flexural surfaces and interiginous areas, and it is not associated with scaling. Eruptive psoriasis: It involves the upper trunk and upper extremities. Most often, it is seen in younger patients. Other forms: Psoriatic erythroderma is a generalized form. When the scales are removed, small droplets of blood appear within a few seconds; this is known as the Auspitz sign. KObner phenomenon is the appearance of psoriatic lesions in previously uninvolved areas after irritation or trauma. Biopsy of the skin lesion may reveal basal cell hyperplasia, proliferation of subepidermal vasculature, absence of normal cell maturation, and keratinization.