TY - CHAP M1 - Book, Section TI - Psoriasis A1 - Hardin, J. Matthew A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason Y1 - 2021 N1 - T2 - The Atlas of Emergency Medicine, 5e AB - Psoriasis has many forms. The most common is chronic plaque psoriasis with stable, symmetric lesions on the trunk and extremities, especially the elbows and knees. Lesions are well-defined, erythematous plaques with silvery scales. Inverse psoriasis represents a form that involves the intertriginous areas, and due to the moist environment, the silvery scale is absent. Guttate psoriasis, common in children and young adults, presents with an abrupt eruption of 2- to 5-mm erythematous scaly papules on the trunk and extremities. A preceding respiratory infection, usually streptococcal pharyngitis, can be a precipitant of guttate psoriasis. Pustular forms of psoriasis can present as localized (nail bed, finger, palms, or soles) or generalized. It is characterized by erythema and “lakes of pus.” Triggers for pustular psoriasis include steroid withdrawal (as in patients with chronic obstructive pulmonary disease [COPD] and asthma exacerbations), pregnancy, infections, and topical irritants. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/03/29 UR - accessmedicine.mhmedical.com/content.aspx?aid=1181044155 ER -