Sarcoidosis with small syringotropic granulomas presenting clinically as a pigmented purpuric dermatosis: Inconspicuous clinical and histopathological clues to systemic illness

摘要

Sarcoidosis is a multisystem granulomatous disease with a myriad of clinical manifestations and a predilection to involve the lungs, eyes, lymph nodes, and skin. A 38-year-old man presented to dermatology with a history of progressive dyspnea, pulmonary consolidations on chest X-ray, and hilar adenopathy on computed tomography scan. Skin exam revealed asymptomatic, yellow to brown macules on the right lower extremity. Biopsy of a lesion showed diminutive syringotropic granulomas and perivascular hemosiderin; stains for bacteria, mycobacteria, and fungi were negative. Subsequent fine needle aspiration of a hilar mass revealed non-necrotizing epithelioid granulomas further supporting a diagnosis of sarcoidosis. The patient was placed on systemic steroids and had improvement of his pulmonary symptoms and stabilization of his hilar lymphadenopathy without resolution of his pigmented purpuric dermatosis (PPD) like lesions. Only three prior cases of syringotropic sarcoidosis have been reported; however, the biopsies had revealed conspicuously large granulomas in contrast with the small granulomas in our case, and none of the prior patients had clinical examination findings that mimicked PPD. Recognition of rare dermatologic and histopathological appearances of sarcoidosis is paramount as cutaneous sarcoidosis may be the harbinger of a systemic illness, which requires a timely diagnosis.