Fast Five Quiz: How Much Do You Know About Psoriatic Arthritis?

Eric M. Ruderman, MD


December 23, 2021

Scaly erythematous lesions, guttate lesions, and erythroderma are skin changes associated with PsA. Scaly erythematous lesions appear in the same manner as a typical psoriasis rash. Guttate psoriasis lesions are small (1-10 mm), drop-like, erythematous to salmon-pink papules. Patients with pustular psoriasis develop small white pustules that spread and join together to form what is referred to as "lakes of pus," which eventually peel off in a sheet-like pattern to reveal erythemic underlying skin. Erythroderma is a deep red rash that forms over the whole body, leaving the appearance of burned skin. Patients with PsA may present with or without skin involvement.

A unilateral, painful, blistering dermatomal rash accompanied by flu-like symptoms is characteristic of herpes zoster (shingles).

A single circular erythemic area with a central bull's-eye is characteristic of erythema migrans, a rash caused by Lyme disease.

Erythemic papules (sometimes blister-like in appearance) in and around the mouth and on the hands and feet are characteristic of hand-foot-and-mouth disease (HFMD; coxsackievirus A type 16).

Learn more about cutaneous manifestations in PsA.


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