Transbronchial lung biopsy in patients with diffuse parenchymal lung disease without ‘idiopathic pulmonary fibrosis pattern’ on HRCT scan - Experience from a tertiary care center of North India

BACKGROUND: Diffuse parenchymal lung diseases (DPLD) are a group of disorders characterized by chest radiological findings of bilateral diffuse shadowing. Lung biopsy is generally required to make an etiological diagnosis of DPLD's. Transbronchial lung biopsy (TBLB) is a minimally invasive method to achieve a lung sample which has been found to be a useful diagnostic tool in patients with DPLD. As per American Thoracic Society guidelines for management of idiopathic interstitial pneumonias, TBLB is not required in patients who have findings consistent with idiopathic pulmonary fibrosis (IPF) on HRCT scan thorax. Some Indian researchers have evaluated, on a small number of subjects, the role of TBLB in patients with DPLD, but they had not excluded patients with ‘IPF pattern’. This study was planned to assess TBLB in patients with DPLD after excluding patients with ‘IPF pattern’. MATERIALS AND METHODS: A prospective non-randomized study on 49 patients with DPLD without a characteristic ‘IPF pattern’ were subjected to TBLB. RESULTS: The overall diagnostic yield of TBLB was 85.7%. Non-specific interstitial pneumonitis, tuberculosis and sarcoidosis were the most common histology patterns found (22.4, 18.4 and 16.3%, respectively). Procedure-related mortality was nil. Iatrogenic pneumothorax occurred in five patients (10.2%). Minor complications included hemorrhage and transient hypoxia. CONCLUSION: TBLB is a safe and effective tool in the diagnosis of DPLD.