Clinical Challenge: Deeply Hyperpigmented, Slightly Raised Papules

Lichen planus is a pruritic disorder of unknown etiology that classically presents as violaceous papules on the wrists and ankles. The pathogenesis is believed to involve an abnormal immune response.1 The condition tends to wax and wane in intensity and...

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Lichen planus is a pruritic disorder of unknown etiology that classically presents as violaceous papules on the wrists and ankles. The pathogenesis is believed to involve an abnormal immune response.¹ The condition tends to wax and wane in intensity and may remit spontaneously after a variable time period. Oral involvement is characterized by white lacey discoloration of the buccal mucosa and at times by refractory ulcerations. A significant percentage of those with lichen planus test positive for hepatitis C.^2,3 Lichen planus may be precipitated by taking certain drugs, including beta-blockers, nonsteroidal anti-inflammatory drugs, and angiotensin-converting enzyme inhibitors.⁴ 

Lichen planus most commonly affects middle-aged individuals and occurs with equal frequency in males and females.⁵ A racial predilection has not been demonstrated, and literature review found no studies citing an increased incidence in the adult Hispanic population. In darker-skinned individuals, postinflammatory hyperpigmentation is characteristically present, as evidenced by this case. The patient in this case received intramuscular triamcinolone acetonide and was prescribed clobetasol cream to be used as topical therapy.

Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. He practices dermatology in Hazleton, Pennsylvania.

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