Abstract
Lymphangiomatosis, a rare systemic condition characterized by abnormally dilated lymphatic structures affecting multiple organs, is typically diagnosed using surgical lung biopsy or lymphangiography, both of which present significant technical challenges. Here, we report the first case of lymphangiomatosis diagnosed using transbronchial lung cryobiopsy (TBLC) in a 20-year-old asymptomatic man. The medical history of the patient was unremarkable, and chest computed tomography revealed diffuse interstitial thickening, ground-glass opacities, and pericardial effusion. Abdominal imaging indicated multiple low-attenuation nodules in the mesentery, omentum, and retroperitoneal areas. Positron emission tomography-computed tomography revealed no abnormal fluorodeoxyglucose uptake in any lesion. TBLC specimens had irregularly dilated lymphatics in the interlobular septa and around vascular bundles, as well as peripheral alveolar walls showing lymphatic dilations positive for D2-40, confirming lymphangiomatosis. The patient was asymptomatic, and careful follow-up was initiated without treatment. This case demonstrates that TBLC may serve as an effective, minimally invasive diagnostic tool for lymphangiomatosis. Early diagnosis during the asymptomatic phase may be crucial given the potential for severe complications associated with thoracic involvement.