Polymorphic light eruption

Diagnosis: Polymorphic light eruption

Polymorphic light eruption

Clinical Presentation

Polymorphic light eruption

Clinical History

Submitted by Ellie Goulding MD. Originally posted January 23, 2017.

Treatment

See case discussion.

Differential Diagnosis

• Lupus erythematosus • Solar urticaria • Photoallergic drug eruption • Erythema multiforme • Actinic prurigo • Porphyria

Key Learnings

• Most common photodermatosis — pruritic papules/plaques on sun-exposed skin in spring/early summer • "Hardening" phenomenon: lesions improve with repeated sun exposure as summer progresses • Consistent morphology within individual patients but polymorphic between patients • Delayed onset: hours to days after UV exposure (distinguishes from solar urticaria) • More common in fair-skinned, females, and in northern latitudes • Photoprotection and controlled phototherapy ("desensitization") before summer are effective

Tags: polymorphic, light, eruption, ellie goulding md