Pulmonary Nodular Lymphoid Hyperplasia in the Eye of Radial Endobronchial Ultrasound

Abstract

Pulmonary nodular lymphoid hyperplasia (PNLH) is a rare, benign lymphoproliferative disorder often manifesting as a solitary pulmonary nodule (SPN). Once a malignant cause of SPN is ruled out, it presents a diagnostic dilemma to clinicians due to histopathological overlap with diseases like mucosa-associated lymphoid tissue (MALT) lymphoma and IgG4-related sclerosing disease. We report an adult patient who presented with incidental finding of a SPN, and was subsequently diagnosed with PNLH via a combined technique of radial-endobronchial ultrasound (R-EBUS), virtual bronchoscopic navigation (VBN), and cryobiopsy. We discuss the sonographic appearance and histopathological morphology of PNLH, and the merits of bronchoscopic techniques in averting surgical intervention of SPN. This is the first reported sonographic appearance of PNLH under radial-endobronchial ultrasound (R-EBUS).