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Training Level

Resident PGY 2


Henry Ford Hospital


HISTORY: A 47-year-old African American man with no relevant past medical history presented to Dermatology with a rash that began 2-3 years prior with a sudden onset on the arms and knees and has since spread diffusely. He endorses oral involvement. Denies any history of hepatitis C, syphilis, or HIV. No family history of similar condition.

EXAMINATION: Diffusely on the body were many hyperkeratotic scaly papules coalescing into plaques with underlying violaceous macules and patches on the arms, legs, buttocks, and hips. Many papules and plaques were in a linear distribution, suggesting possibility of koebnerization. The mouth had hyperkeratotic papules along the oral commissures, cobblestoning of the palate, and reticulated white streaks on the upper and lower mucosal lip and the left buccal mucosa.

HISTOPATHOLOGY: Pathology revealed marked verrucous epidermal hyperplasia with overlying parakeratosis and neutrophils in the stratum corneum. A lichenoid infiltrate at dermal-epidermal junction and necrotic keratinocytes were also seen. Negative HPV staining.

DIFFERENTIAL DIAGNOSIS: Hypertrophic lichen planus (HLP) vs keratosis lichenoides chronica (KLC) vs less likely extensive verruca.

LABORATORY: CBC and CMP within normal limits. Hepatitis C, syphilis, and HIV negative.

DIAGNOSIS: The KLC and HLP present similarly histologically with hyperkeratosis and lichenoid infiltrate with interface change. Given clinical similarity, both are high in the differential in this case. KLC was favored due chronicity of individual lesions and due to the confluent parakeratosis and corneal neutrophils seen on pathology which are uncharacteristic of HLP.

COURSE AND THERAPY: At time of presentation, he was on a regimen of acitretin 50 mg daily, betamethasone dipropionate ointment to the body, and tacrolimus 0.1% ointment to the face without significant improvement. Patient was continued on topical steroids and acitretin, and was also started on CellCept 500mg BID, later increased to 1000mg BID.

DISCUSSION: HLP and KLC can present similarly with erythematous to violaceous hyperkeratotic papules and plaques. These are usually present on the lower extremities but may present more diffusely, including on the trunk and face. KLC is a rarer condition with a chronic course. Lesions can be pruritic and are typically in a reticular or linear pattern as seen in our patient. Oral and nail involvement, as in our patient, have been reported in about 20-30% of patients. KLC also may present with facial eruption similar to seborrheic dermatitis or rosacea. KLC may present at any age and has a slight male predominance. The etiology of this condition is unknown and given its similarity to other keratotic skin diseases as well as its rarity, it has not been well-studied. Although difficult to treat, oral retinoids such as acitretin and phototherapy have had some documented efficacy in treating KLC.HLP is a variant of lichen planus (LP) with a similar presentation of hyperkeratotic papules and plaques and usually a more chronic course. Lesions often are pruritic and koebnerization may play a role, causing more linear formations. Oral involvement, particularly Wickham striae, or nail changes may also be observed. Given longstanding inflammation, hypertrophic LP may develop malignant transformation to squamous cell carcinomas or keratoacanthomas. Treatments for HLP include topical or intralesional corticosteroids, methotrexate, metronidazole, cyclosporine, dapsone, azathioprine, and phototherapy. Acitretin and mycophenolate mofetil (CellCept) have shown efficacy in resistant HLP.

Presentation Date


A man with diffuse hyperkeratotic papules and plaques