Diffuse Parenchymal Lung Diseases with Clinicoradiological Discordance: Role of Transbronchial Lung Biopsy as a Diagnostic Tool - An Observational Study

Introduction: The diagnosis of Diffuse Parenchymal Lung Disease (DPLD) requires a multidisciplinary approach with reconciliation of clinicoradiological and histopathological data. But when the preliminary clinicoradiological profile fails to suggest a diagnosis, an adequate lung biopsy specimen with meticulous histological examination and a multidisciplinary approach usually yields results. There is also a high chance of sampling error due to patchy and heterogeneous involvement of the disease process and due to the small volume of tissue taken. As seen in our study, Trans-Bronchial Lung Biopsy (TBLB) if performed by an experienced bronchoscopist can be done as an outpatient procedure yielding adequate specimens for diagnosis and guide effective treatment in these patients.

Aim: To study the utility and diagnostic yield of TBLB in DPLD patients when there is clinicoradiological discordance.

Materials and methods: The current retrospective observational study was undertaken in the Institute of Chest Diseases, Government Medical College, Kozhikode, Kerala, India, from January 2012 to December 2014. Out of 169 DPLD patients who attended the tertiary care centre, 66 patients without a definite diagnosis by clinicoradiological assessment were included in the study. They underwent TBLB using a fibre-optic video bronchoscope. An open lung biopsy was advised if the TBLB did not yield a definite diagnosis.

Results: Among the 66 patients, histopathological confirmation was obtained in 51 patients, 39 of which were by TBLB (59%). Few diagnoses like invasive adenocarcinoma, Pneumocystis jirovecii pneumonia and Aspergillus infection were least expected.

Conclusion: TBLB if performed correctly can be an effective intervening modality in establishing the diagnosis of DPLD before going for an invasive surgical biopsy.