Diagnostic sensitivity of bronchoalveolar lavage versus lung fine needle aspirate

Abstract

Bronchoalveolar lavage (BAL) and lung fine-needle aspirate (LFNA) are commonly performed as the first line of investigation for a myriad of pulmonary problems associated with abnormal imaging findings (mass, cavitary lesion, infiltrates, etc.). The relative sensitivities of these two procedures are not well established for cytologic diagnosis of lesions for any single disease event. Records were searched for single pulmonary disease events with closely timed BAL and LFNA, as defined by both procedures occurring within <or=8 days of each other. No samples with "unsatisfactory" diagnoses were considered for the analyses. Success of identifying malignancy and/or an infectious agent was recorded for both procedures. Between January 1989 and June 2000, 52 episodes of closely timed (65% within 3 d) BAL and LFNA procedures were identified in 45 patients for a single disease event. The clinical scenarios as per the sample requisitions were as follows: consolidation/infiltrate (60%), mass/nodule (23%), cavitary lesion (5.7%), pneumonia (5.7%), or not specified (5.7%). For all cases examined (n = 52), in 18 (35%) of the episodes, LFNA uniquely identified either malignancy, 6/18 (12%), or infectious agents such as Aspergillus and acid-fast bacteria, 12/18 (23%), with a corresponding nondiagnostic BAL. In one episode with a clinical diagnosis of infiltrates, the BAL was positive for acid-fast bacteria, whereas the LFNA was negative. Chi-square analysis of the data revealed statistical significance with P <.0001 with 2 degrees of freedom, indicating LFNA to be a superior method for the diagnosis of pulmonary pathology over BAL. Based on our data, LFNA is the superior method for the cytologic diagnosis of pulmonary pathology amenable to cytologic examination.