Bronchoalveolar lavage and transbronchial lung biopsy in alveolar and/or ground-glass opacification

Abstract

In order to assess the diagnostic yield of bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBB) in pulmonary diseases with a ground-glass and/or alveolar pattern on high-resolution computed tomography (HRCT) scan, a prospective study was undertaken. Thirty-six patients (17 males, 19 females), mean age 53 yrs, selected on the basis of the presence of an alveolar and/or ground-glass pattern on chest HRCT scan, were submitted to fibreoptic bronchoscopy. All patients underwent BAL. TBBs were performed in 33 cases. A specific diagnosis was achieved, taking into account data obtained by means of serology, microbiology, cytology and histopathology in appropriate clinical settings. Twelve (33%) patients only had the appearance of a ground-glass opacity, whereas 24 (67%) had associated areas of airspace consolidation. BAL was performed in all cases and gave a definitive diagnosis in 21 (58%). The diagnostic yield of BAL in patients with only ground-glass opacities was no different from that in those patients also showing areas of alveolar consolidation (58 versus 58%). In eight patients (six with ground-glass opacity and two with alveolar consolidation), BAL provided useful but not definitive information. In these patients, a definitive diagnosis was achieved by means of TBB in seven cases and by open lung biopsy in one case. TBB was performed in 33 out of 36 patients and gave positive results in 25 (76%). The diagnostic yield of TBB in patients showing areas of alveolar consolidation was significantly higher than in those with pure ground-glass opacity, i.e. 95% (21 of 22) and 36% (4 of 11) respectively (p < 0.001). BAL and TBB were performed during the same bronchoscopy in 33 patients, and an accurate diagnosis was achieved in 30 (91%). Overall, the diagnostic yield of TBB (76%) and BAL (56%) did not differ significantly in the whole patient group (p = 0.12), or in patients with a ground-glass opacification (58 versus 36%, p = 0.3). However, in patients with areas of alveolar consolidation, the diagnostic sensitivity of TBB (95%) was significantly greater than the diagnostic sensitivity of BAL (54%) (p = 0.03). In conclusion this study shows that high-resolution computed tomography can be helpful in predicting the diagnostic accuracy of bronchological procedures, in particular of bronchoalveolar lavage and transbronchial biopsy, and that alveolar and/or ground-glass are favourable patterns for these diagnostic tools.