Stage related morphometry of sarcoid granulomas and inflammatory cell types in broncho-alveolar lavage.

The epithelioid granulomas, interstitial and intra-alveolar mononuclear inflammatory infiltrates and the cellular compartments obtained by broncho-alveolar lavage (BAL) were measured in 40 patients with pulmonary involvement of sarcoidosis. The granulomas were divided into a central (epithelioid-cellular) zone and into a peripheral (lymphocytic-fibrotic) zone, and the density of various inflammatory cells was measured in both compartments. The cases were grouped and analyzed according to the radiological and clinical stages. The results are as follows: neutrophilic granulocytes seen in the BAL probably originate from the sarcoid granulomas in patients with stage 1 of the disease and may derive from other compartments of the lung parenchyma in patients with stage 2 or stage 3. Lymphocytes seen in the BAL of patients with stage 1 or stage 2 of the disease probably derive from intra-alveolar lymphocytic agglutinations. They originate from the sarcoid granulomas only in patients with stage 3. Macrophages seen in the BAL probably derive from the sarcoid granulomas independent from the stage of sarcoidosis. No relationship was found between the morphometric parameters and the clinical outcome of the disease.