Clinical usefulness of bronchoalveolar lavage in patients with interstitial lung diseases: a pilot study

Background: Bronchoalveolar lavage (BAL) is a useful tool in the diagnostic work-up of patients with interstitial lung diseases (ILDs). In this prospective study, we investigated the clinical usefulness of BAL in patients with ILD radiographically. Methods: The enrolled patients were classified into outpatient department (OPD), and inpatients groups who was admitted to general ward (GW) or intensive care unit (ICU) groups based on the time when BAL done. The clinical usefulness of BAL was defined as a new diagnosis established and/or treatment significantly changed. The clinical usefulness of BAL among the three groups of patients and the patients divided by underlying diseases was compared using the chi(2) test with or without Fisher's exact test. Results: Among our 184 patients, there were 37 in OPD group, 86 in GW group and 61 in ICU group. The final diagnoses were infectious in 23, non-infectious in 102, mixed etiologies in 19, and non-diagnostic in 40 patients. The diagnostic yields (revised diagnosis after BAL) of BAL among ICU patients, GW patients and OPD patients were 60.6%, 69.7% and 21.6%, respectively (P<0.001), and was 57.1% in total patients. The diagnostic yields of BAL, among patients with cancer, organ transplantation and collagen vascular disease were statistically different (P=0.009). Conclusions: BAL is of use in establishing a diagnosis of ILD and is mandatary especially in the admitted patients with ILD because diagnostic yield was relatively higher in admitted patients than in OPD patients. In addition, BAL should be done more early in the admitted patients with malignancy, stem cell and/or organ transplantation and collagen vascular disease especially when they showed poor response to initial medications.