Testing the waters: the potential of urinary proteomics in congenital diaphragmatic hernia and Tetralogy of Fallot

Congenital diaphragmatic hernia (CDH) is a structural birth defect with an incidence of approximately 1 in 3000. 1 It is due to abnormalities in the development of the pleuroperitoneal folds resulting in herniation of the abdominal organs into the thoracic cavity, impairing proper lung development and function. As a result, patients suffer from pulmonary hypertension (PH), attributed to high pulmonary vascular resistance and abnormal vascular remodeling. 2 , 3 These vascular pathologies ultimately cause significant stress to the right ventricle (RV). Similar RV dysfunction, a leading cause of morbidity and mortality in neonates, is observed in patients with Tetralogy of Fallot (TOF), a congenital disorder caused by a combination of cardiovascular lesions involving ventricular septal defect, overriding aorta, pulmonary stenosis, and RV hypertrophy that occurs in about 3 out of 10,000 births. 4 While CDH and TOF are developmentally different disorders, both often result in PH and eventual RV dysfunction. In CDH, PH is attributed to high pulmonary vascular resistance, while in TOF, PH is primarily due to pulmonary outflow tract stenosis.