Sarcoidosis has been called the greatest mimic. What reasons can you think of for this moniker?
Sarcoidosis has numerous manifestations in the lung including miliary disease, consolidation, nodules and masses. Disease can affect many different organs and systems: the heart, liver, spleen, lymph nodes, central nervous system, musculoskeletal system, skin, eye, etc.
18G core biopsies had a granular appearance. Important to avoid the oblique fissure and pulmonary blood vessels.
The core biopsies of pulmonary parenchyma and airway wall tissue show "innumerable" well-formed, non-necrotising, granulomata composed of tight aggregates of epithelioid histiocytes and multinucleated giant cells within airway wall tissue (lamina propria and submucosa), alveolar walls and possible septa. Air-space granulomata are not noted. Small numbers of lymphocytes are present within and surrounding the granulomata but there is no acute neutrophilic inflammation and eosinophils are inconspicuous. No refractile foreign material is identified. There is no significant airspace inflammation. Features of organising pneumonia are not noted. Special stains (DiPAS and Methanamine silver) do not show fungi. The Gram stain for bacteria is negative The Putt stain for acid-fast bacilli is negative. There is no evidence of malignancy. The histological features are those of granulomatous inflammation. The appearances and distribution of the granulomata are consistent with sarcoid. Infection should be excluded by correlation with microbiological studies.