EIF2AK4 and Pulmonary capillary hemangiomatosis: Recent discoveries have indicated that gene mutations in eukaryotic translation initiation factor 2 alpha kinase 4 (EIF2AK4) are responsible for inherited PVOD and pulmonary capillary hemangiomatosis (PCH) [18], and the 2015 ESC/ERS Guidelines declared that identification of a biallelic EIF2AK4 mutation was sufficient to make a diagnosis of PVOD/PCH without histological confirmation [1].