DP03 Psoriasiform lesions in a patient with pulmonary disease

Abstract Psoriasiform sarcoidosis is a rare variant of cutaneous sarcoidosis, characterized by erythematous, raised, scaly plaques that resemble psoriasis. The condition can be difficult to differentiate from other dermatological conditions (Yanardag H, Tetikkurt C, Bilir M et al. Clinical significance of psoriasiform sarcoidosis. Arch Clin Med Case Rep 2020; 4: 471–82). Herein, we report the case of a 38-year-old man who presented with a 7-month history of progressively worsening cutaneous lesions, along with a 5-year history of shortness of breath, currently classified as Modified Medical Research Council grade III. On examination, erythematous annular plaques with peripheral scaling and central clearing were noted on his face, and reddish-orange plaques with adherent whitish scales and superficial crusting were observed on the lower extremities. Dermoscopy revealed yellow-orange structureless areas, glomerular vessels and polarizing white lines, which are characteristic of sarcoidosis. A chest computed tomography (CT) scan showed cavitary lesions, lobular septal thickening and enlarged hilar lymph nodes, indicative of pulmonary involvement. Histopathological examination of a punch biopsy from the lower legs showed well-formed non-necrotizing granulomas, composed of epithelioid cells with multinucleated giant cells extending into the subcutis, confirming sarcoidosis. Staining for acid-fast bacilli and fungus was negative. CT-guided aspiration of the hilar lymph nodes revealed noncaseating granulomas, and bronchioalveolar lavage was negative for infectious agents, further supporting the diagnosis of psoriasiform sarcoidosis. Psoriasiform sarcoidosis is a rare and often aggressive form of sarcoidosis, with a poor prognosis due to its multisystem involvement. It accounts for only 0.9% of all cases of sarcoidosis. Differentiation from conditions such as necrobiosis lipoidica, psoriasis, granulomatous mycosis fungoides and interstitial granulomatous dermatitis is difficult, but dermoscopic and histopathological findings are key to making the correct diagnosis. Treatment typically involves systemic steroids for acute disease, with steroid-sparing agents such as methotrexate or hydroxychloroquine used for long-term management. Early diagnosis and appropriate treatment are critical to managing the disease’s progressive nature and avoiding complications.