The varied clinical symptomatology results from infiltration of specific organs. Because the initial manifestation is usually respiratory, an exogenous airborne agent is the suspected culprit. Diagnosis is based upon radiologic identifications of both the distinctive lung infiltrates and hilar lymphadenopathy and biochemical changes.
Final diagnosis awaits the histologic demonstration of the granulomas in other organ structures.
Non caseating granulomas with a core of epithelioid and giant cells and a periphery of lymphocytes and fibroblasts are characteristic. The spectrum can be classified into 4 symptom complexes. First, patients already diagnosed with sarcoidosis often develop salivary gland swelling. Usually, bilateral parotid gland swelling is seen. The glands tend to be firm, only slightly tender, and do not fluctuate in size when eating.