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.
Psoriasis. Annular, well-defined plaque on the shin. (Photo contributor: J. Matthew Hardin, MD.)
Management and Disposition
ED management should ensure there is no infectious etiology or systemic symptoms. Localized psoriasis typically responds to topical glucocorticoids, although the chronicity and variety of other management options, including phototherapy, should prompt referral to dermatology. Pustular forms may be challenging and require admission. Guttate psoriasis may respond to antistreptococcal antibiotics. Obtain emergent consultation with a dermatologist for patients with generalized presentations (erythrodermic patients) and referrals for localized disease.
Psoriasis. Classic silvery scale associated with longstanding lesions. (Photo contributor: J. Matthew Hardin, MD.)
The increase in biologic medications and immunosuppressants used for psoriasis can make serious infections a major concern.
Medication-induced psoriasis is associated with β-blockers, lithium, interferon, and antimalarials.
Patients with psoriasis have a higher incidence of coronary artery disease, obesity, tobacco use, and alcoholism.
Psoriasis. Note the erythematous plaques with diffuse fissuring in this case of palmar psoriasis. (Photo contributor: J. Matthew Hardin, MD.)
Psoriasis. Erythematous plaques on the upper arm and hand. (Photo contributor: J. Matthew Hardin, MD.)
Psoriasis. Erythematous plaques on the forehead and scaling in the scalp. (Photo contributor: J. Matthew Hardin, MD.)
Plaque Psoriasis. (Photo contributor: Lawrence B. Stack, MD.)