Can you identify these pruritic, annular plaques?

Dermclinic
A Photo Quiz to Hone Dermatologic Skills 

Since the onset of spring several weeks earlier, pruritic, annular plaques have developed on the sun-exposed areas of a 46-year-old woman’s arms, legs, upper chest, and upper back. Applications of SPF 30 sunscreens have not helped. The patient is otherwise healthy and denies taking prescription or over-the-counter medications.

What are you looking at here?

A. Polymorphous light eruption.

B. Systemic lupus erythematosus.

C. Subacute cutaneous lupus erythematosus.

D. Discoid lupus erythematosus.

E. Granuloma annulare.

(Answer and discussion on next page)

ANSWER—Case 3: Subacute cutaneous lupus erythematosus

A biopsy confirmed the clinical impression of subacute cutaneous lupus erythematosus, C, which usually presents with erythematous papules and plaques that primarily involve the face. Unlike the lesions of discoid lupus erythematosus, these annular, erythematous, scaling plaques heal without scarring. Polymorphous light eruption presents as itchy, small papules and annular plaques without scale. Generally, granuloma annulare is asymptomatic and does not scale.