Neonatal hypertension caused by left-to-right shunt flow through a patent ductus arteriosus in a premature infant

Abstract

Abstract Objectives Though it is rare and challenging to study, neonatal hypertension (HTN) has been explored and studied by many pediatricians. There were some causes reported in preterm infants such as renal diseases and bronchopulmonary dysplasia. Case presentation We report a premature female infant who was born at a gestational age of 25 + 6 weeks and developed systemic hypertension on the day of a gestation age of 30 + 3 weeks. This case had a rare cause which involved high-normal serum aldosterone level that could possibly indicate hyperaldosteronism and over-stimulation of renin–angiotensin–aldosterone system (RAAS). We believe elevation of serum aldosterone was caused by a left-to-right shunt flow through a patent ductus arteriosus. Hypertension due to a patent ductus arteriosus sounds like a paradox. However, in our case, the shunt flow was shown to be a possible cause of the systemic hypertension. Surgical closure of the shunt was done and the hypertension resolved. We evaluated serum aldosterone levels and plasma renin activities both, before and after the closure to look for a possible cause. Conclusions Neonatologist often treats systemic hypertensive infants considering possible causes in order to prevent hypertensive crisis. Our case shows that possibility of hyperaldosteronism and (RAAS) over-stimulation should be considered as causes in case of severe systemic hypertension in preterm infants with large left-to-right shunt flows.