Psoriasiform Sarcoidosis: Collision of Two Entities or Expression of One Common Pathogenesis?

Abstract

Background: Psoriasiform lesions are an established, but rare, manifestation of sarcoidosis. Only 0.9 percent of patients with cutaneous sarcoidosis develop this form of the disease.

Observation: The authors present a case of a 61-year-old woman with a history of pulmonary sarcoidosis who presented to their dermatology clinic with thick plaques resembling psoriasis. Biopsy of one of the lesions revealed sarcoidal granulomas in association with psoriasiform changes.

Conclusion: Psoriasiform lesions are a rare manifestation of sarcoidosis. The authors theorize that the co-expression of TNF-α in both entities is a possible explanation of the psoriasiform expression of sarcoidosis.

Figure 1.

Hyperkeratotic plaques on right leg

Figure 2.

Annular plaque lesion with central atrophy on left cheek

Figure 3.

Non-caseating granulomatous inflammation of the dermis in a biopsy of a pretibial plaque.

Figure 4.

Corneal microabscess containing neutrophils with a surrounding parakeratotic scale and hypogranulosis in the same biopsy specimen as Figure 3.