Immunology

The pathologic hallmark of sarcoidosis is discrete, compact

non-caseating granulomas. The granulomas comprise mainly

epithelioid cells with CD4 lymphocytes, mature macrophages

and multinucleated giant cells interspersed throughout the

epithelioid core and CD8 lymphocytes in the periphery. The

granulomatous inflammation leads to distortion of local

architecture, tissue injury and fibrosis.