EIF2AK4 mutation in pulmonary veno-occlusive disease: A case report and review of the literature

BACKGROUND: Pulmonary veno-occlusive disease (PVOD) is a rare and devastating cause of pulmonary arterial hypertension with a non-specific clinical presentation and a relatively specific presentation in high-resolution thoracic CT scan images. Definitive diagnosis is made by histological examination in previous. According to the 2015 ESC/ERS Guidelines, detection of a mutation in the eukaryotic translation initiation factor 2 alpha kinase 4 (EIF2AK4) without histological confirmation is recommended to validate the diagnosis of PVOD. METHODS: We report the case of a 27-year-old man who was admitted for persistent cough and dyspnea that had lasted for 5 months and had developed and experienced progressive dyspnea for the last 2 months. The echocardiogram and right heart catheterization without vasodilator challenge confirmed the diagnosis of pulmonary arterial hypertension. Other tests, such as high-resolution thoracic CT scan, V/Q scan, pulmonary function test with diffusion capacity, and blood tests, excluded other associated diseases which could have caused pulmonary hypertension. RESULTS: The initial diagnosis at admission was idiopathic pulmonary arterial hypertension and an oral vasodilator (sildenafil) was given. However, the dyspnea subsequently worsened, and the patient was transferred to a regional lung transplant center, where he died of heart failure 1 week later. Using exome sequencing, we found an EIF2AK4 mutation, which was sufficient to confirm the diagnosis of PVOD. CONCLUSION: This is the first reported case of EIF2AK4 mutation in PVOD in a Chinese patient population. We found the frameshift EIF2AK4 mutation c.1392delT (p.Arg465fs) in this case. Up to now, there has been a paucity of data on this rare disease, and the exact role of EIF2AK4 loss-of-function mutations in the pathogenesis of PVOD is still unknown. More investigations should be conducted in the future.