Transbronchial cryobiopsy validity in diagnosing diffuse parenchymal lung diseases in Egyptian population

Abstract

Objectives: We aimed to evaluate the efficacy, safety, and diagnostic utility of transbronchial cryobiopsy (TBCB) in diagnosing diffuse parenchymal lung diseases (DPLDs) in an Egyptian population and to identify common DPLD pathologies among them.

Methods: This prospective interventional study enrolled 25 Egyptian patients presenting to the Main Alexandria University Hospital who had clinical and radiological features of DPLD, but insufficient elements to achieve definite features of usual interstitial pneumonia on chest high-resolution computed tomography. Twelve patients were subjected to TBCB and 13 to forceps transbronchial lung biopsy (TBLB).

Results: The diagnostic yield was significantly higher among the TBCB group (83.3%), and increased to 100% with clinicopathological correlation vs the TBLB group (38.5%, P=0.041). Granulomatous diseases (24%, either sarcoidosis or hypersensitivity pneumonitis) were the commonest pathology, followed by malignancy (12%) in both groups. TBCB sizes were 2.5-5 mm vs 1-3 mm in TBLB (P<0.001), with preserved tissue architecture (91.7% vs 38.5%, respectively; P=0.011). Only 8.3% were complicated by insignificant bleeding grade 2 after TBCB, but no pneumothorax was detected.

Conclusion: TBCB is a safe, tolerable procedure with high diagnostic yield for evaluating DPLD with indefinite usual interstitial pneumonia pattern on high-resolution computed tomography.

Keywords: bronchoscopy and interventional techniques; interstitial lung diseases; pathology.

Figure 1

Histopathological examples of those with proved diagnosis in forceps transbronchial lung biopsy group. Notes: (A) Noncaseating granuloma composed of epithelioid cells and multinucleated giant cells (H&E, 100×); (B) lymphangitis carcinomatosis, with submucosal edema, mononuclear inflammatory infiltration, tiny clusters of epithelial malignant tumor cells within dilated spaces (lymphatic), and vessels denoting lymphatic tumor emboli (H&E, 40×); (C, D) pulmonary alveolar proteiniosis showing alveolar exudates with an eosinophilic granular appearance, scattered larger inclusions with more intense eosin staining, and slight retraction effect at the periphery of the alveoli (H&E [C], positive periodic acid–Schiff [D], 100×).

Figure 2

Histopathological examples of those with proved diagnosis in transbronchial cryobiopsy group. Notes: (A) Mucinous carcinoma showing glands lined with tall columnar mucus secretory cells with abundant mucin-containing cytoplasm and mucin pools with floating malignant cells (H&E, 40×). (B) cellular nonspecific interstitial pneumonia, with alveolar wall heavily infiltrated with plasma cells, lymphocytes, histocytes, and minimal fibrosis (H&E, 400×); (C) poorly formed granuloma (hypersensitivity pneumonitis) composed of lymphocytes, histocytes, neutrophils, and plasma cells (H&E, 40×); (D) noncaseating granuloma (sarcoidosis) composed of epithelioid cells and multinucleated giant cells (H&E, 100×).