Pulmonary capillary hemangiomatosis diagnosed by pathology of explanted lungs: a unique etiology serves as a key of clinical diagnosis

A 27-year-old female patient had presented progressing exertional dyspnea due to pulmonary hypertension. Chest CT revealed diffusely spread patchy ground-glass opacities sparing subpleural parenchymal areas suggesting the diagnosis of pulmonary veno-occlusive disease (PVOD). Despite the diagnosis of PVOD, she was somehow managed by a repetitive escalation of the epoprostenol dose and oxygen supply during the 12-month waiting period until successful bilateral lung transplantation was performed. Pathology demonstrated capillary proliferation in alveolar septae with scarce lesions of narrowed and/or occluded postcapillary small veins, leading to the final diagnosis of pulmonary capillary hemangiomatosis (PCH), not PVOD. We herein present a case of PCH diagnosed after lung transplantation with a focus on its etiology and a key to clinical diagnosis.