Idiopathic Guttate Hypomelanosis

Diagnosis: Idiopathic Guttate Hypomelanosis

Discrete, circular and hypopigmented macules on legs

Clinical Presentation

Discrete, circular and hypopigmented macules on legs

Clinical History

Submitted by Alaa Saad. Originally posted September 13, 2010.

Treatment

See case discussion.

Differential Diagnosis

• Vitiligo • Pityriasis versicolor • Pityriasis alba • Post-inflammatory hypopigmentation • Lichen sclerosus

Key Learnings

• Small (2-5mm), well-defined, porcelain-white macules on sun-exposed extremities • Very common — increases with age, often after 40 • Result of chronic UV exposure → focal melanocyte loss • NOT autoimmune (unlike vitiligo) • Purely cosmetic concern

Tags: idiopathic, guttate, hypomelanosis, alaa saad