Transbronchial cryobiopsy in the diagnosis of the idiopathic interstitial pneumonias

Background Histology is crucial for the multidisciplinary diagnosis of idiopathic interstitial pneumonias (IIP). Transbronchial cryobiopsy (TBC) has been demonstrated to be useful for obtaining lung parenchyma; however its experience in the diagnosis of IIP is limited. Objectives To describe the diagnostic yield and safety of TBC in the study of IIP. Method Prospective study of 23 outpatients of TBC. All cases had the typical clinical and radiological features of IIP. The endoscopic procedure was performed in the operating theatre using a flexible bronchoscope obtaining 3-5 biopsies of lung parenchyma with radiological control. Biopsies were reviewed by the reference pathologist. Results The patients were 65±10-year-old (57% men). The length range of biopsies was 2-7 mm. The sample was adequate (at least 20 alveolar spaces) in 20 patients (87%). The specific diagnosis (confirmed by Multidisciplinary discussion) was obtained in 12 patients (52%): usual interstitial pneumonia (UIP n=9) and nonspecific interstitial pneumonia (NSIP n=3). The complications were: pneumothorax in 2 patients (both required drainage), 4 patients showed significant bleeding (u003e100 ml), one of them severe with respiratory failure but the patient recovered 3 days after. In the remaining patients the diagnosis was reached by VATS (9 patients: UIP [n=5], unclassifiable interstitial pneumonia [n=2], NSIP [n=1] and respiratory bronchiolitis associated to interstitial pneumonia [n=1]), or by clinical and radiological parameters (1 organising pneumonia, 1 UIP). Conclusions In patients with suspected IIP, TBC is useful to obtain lung parenchyma with good yield and avoids in 52% of open biopsies in our population.