Transbronchial cryobiopsy in the diagnosis of desquamative interstitial pneumonia

Safety and accuracy of transbronchial lung cryobiopsy in diagnosing desquamative interstitial pneumonia

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is a new technique to obtain specimens for diagnosis of interstitial lung disease (ILD) in recent years. The objective of this study is to evaluate the safety and the diagnostic accuracy of TBLC in patients of desquamative interstitial pneumonia (DIP).

METHODS

In this study twelve patients confirmed with DIP were selected from January 2019 to December 2020 at the department of pulmonary and critical care medicine in China-Japan Friendship Hospital. All cases underwent TBLC in a hybrid cone beam CT (CBCT) operation room with a single general anesthesia. The definitive diagnosis was made by a multidisciplinary team that involved clinicians, radiologists and pathologists. This study analyzed the biopsy sample surface areas, main complications and the consistency between TBLC pathology and multidisciplinary discussion (MDD) diagnosis for DIP.

RESULTS

An average of 3.1 ± 1.1 specimens were obtained per patient. The mean surface area of the specimen was 23.7 ± 6.1 mm² . None of the cases had pneumothorax or massive hemorrhage. Ten cases (83.3%) had no or mild bleeding and two cases (16.7%) had moderate bleeding. All cases had the typical pathologic characteristics of DIP, which was highly consistent with the diagnosis of MDD.

CONCLUSION

TBLC can obtain sufficient samples for the pathological diagnosis of DIP, which has high security and accuracy in experienced specialist centers.

Transbronchial lung cryobiopsy in smoking-related interstitial lung diseases

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) is an emerging technique in the diagnostic approach to diffuse parenchymal lung diseases. However, the role of TBLC in smoking-related Interstitial Lung Diseases (ILDs) is still under discussion.

OBJECTIVES

The aim of the present study was to describe our experience with TBLC in diagnostic work-up of patients with smoking-related ILDs.

METHOD

We retrospectively reviewed data of patients evaluated in a tertiary hospital ILDs outpatient clinic, who underwent TBLC, from September 2014 to December 2019. TBLC was performed in accordance with the 2018 expert statement from the Cryobiopsy Working Group.

RESULTS

Forty-five patients (25 men [55.6%]) with a mean age of 53.9 years [SD, 9.1] were included. The most frequent radiological pattern was ground glass opacity (42 patients). TBLC was performed in different segments of the same lobe in 38 patients and in two lobes in 7 patients. The mean maximal diameter of the samples was 5.2 mm (range, 3-16 mm [SD 2.0]). Pneumothorax occurred in seven patients (15%) and moderate bleeding occurred in one patient. A specific pathological diagnosis was achieved in 43 of 45 patients. The most frequent histopathologic pattern found was desquamative interstitial pneumonia (33 patients), followed by smoking-related interstitial fibrosis (7 patients), respiratory bronchiolitis - ILD (1 patient) and pulmonary Langerhans cell histiocytosis (1 patient). Two patients had alternative diagnosis (Pneumoconiosis and Interstitial Pneumonia with unspecific features) and one patient had normal lung parenchyma. A definitive multidisciplinary team (MDT) diagnosis was reached in 95.5% (43 of 45 cases). Two patients were submitted to additional diagnostic techniques.

CONCLUSIONS

The results from this series support TBLC as a safe procedure with a meaningful diagnostic value in the context of a MDT approach of smoking-related ILDs. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (4): e2020013).

Smoking Relapse Causing an Acute Exacerbation of Desquamative Interstitial Pneumonia with Pleural Effusions and Mediastinal Adenopathies

Desquamative interstitial pneumonia (DIP) is a rare interstitial pneumonia often caused by smoking. DIP is typically regarded as a chronic disease, but acute DIP exacerbations can occur, and some have resulted in death. Factors that can provoke a DIP exacerbation are not well described in the literature. We present a case of a 58-year-old male with DIP, who after being treated successfully with smoking cessation and steroids for 7 months, required hospitalization for acute hypoxemic respiratory failure. This acute episode was very likely an exacerbation of his DIP after a smoking relapse period of 6 weeks prior to this acute presentation. This report also highlights unique CT findings in a DIP case of pleural effusions and mediastinal adenopathies seen chronically and relapsing acutely. To the best of our knowledge, CT findings of pleural effusions and mediastinal adenopathies concurrently have not been described in a case of DIP in chronic or acute conditions.

Interstitial lung disease: the diagnostic role of bronchoscopy

Interstitial lung diseases (ILDs) form one of the most fascinating fields in pulmonary medicine. They also pose one of the greatest challenges for accurate diagnosis and proper treatment. Even within the recommended and warranted multidisciplinary approach, differentiating between one disease and another may lead to frustration, especially when proper lung tissue is not available for adequate pathological review. A surgical lung biopsy (SLB) might render enough tissue for histopathology, but this could come at the expense of high morbidity and even mortality, as in the case of usual interstitial pneumonia (UIP). Could bronchoscopy and its various techniques offer a safer and higher yield alternative? Since the very late 19th century, efforts have been made to better examine the airways, obtain tissue and treat various conditions. This resulted in the successive emergence of bronchoalveolar lavage (BAL), endobronchial and transbronchial forceps biopsies, until recently when transbronchial cryobiopsy surfaced as a nascent technique with much promise. The use of endobronchial ultrasound revolutionized the diagnosis and staging of lung cancer, while adding to the yield of other conditions such as sarcoidosis. Ongoing research, efforts and studies have continuously scrutinized the roles of various techniques in the approach to ILDs. For example, BAL seems to serve mostly to eliminate infection as an etiology or a complicating factor in the acute worsening of a fibrotic lung disease, while a predominant cellular component might be diagnostic, such as eosinophilia in eosinophilic lung disease, or lymphocytosis in hypersensitivity pneumonitis (HP). On the other hand, endobronchial biopsy's (EBB) role appears limited to sarcoidosis. As for transbronchial biopsy by forceps, the small sample size and related artifact appear to be limiting factors in making an accurate diagnosis. Recently, however, the use of cryotherapy via employing a cryoprobe in obtaining transbronchial lung biopsies is unfolding into a refined interventional method which might transform indefinitely our approach to the pathological diagnosis of the various ILDs.