Open lung biopsy for diffuse infiltrative lung disease.

The purpose of this study was to determine the most appropriate site of biopsy in patients with diffuse infiltrative lung disease (DILD). Twenty patients were evaluated. During open lung biopsy, a representative region (inflamed and least fibrotic) of the radiographically most involved lobe was identified and a biopsy done. A second biopsy specimen was obtained from an adjacent accessible lobe. The biopsy specimen from each lobe was processed separately, and a descriptive histologic report was generated for each of the two lobes. Tissue was cultured for bacteria, fungi, and mycobacteria. In 17 patients, the second biopsy site had fewer roentgenographic abnormalities than the radiographically most involved lobe. In 3 patients, the number of radiographic abnormalities was equal in all lobes. The same pathologic diagnosis was reached by histologic examination of the two biopsy specimens in 8 of 10 patients with acute DILD and in 10 of 10 patients with chronic DILD. In 2 patients, the biopsy specimen from the radiographically most involved lobe showed pathologic features not seen in the other specimen. Cultures from both biopsy specimens were grown separately in 6 patients. Fungi (n = 2) and bacteria (n = 1) were isolated from the radiographically most involved lobe (n = 2) or from the lobe of initial lung infiltration (n = 1) in 3 patients. When biopsy specimens are obtained from a representative region of the radiographically most involved lobe in patients with DILD, biopsy of other lobes is unnecessary.