Hydronephrosis and risk of later development of hypertension

Aim Congenital ureteral obstruction is a fairly common condition in infants, and its clinical management has been long debated during the last decade. The long‐term physiological consequences of today's conservative non‐surgical management in many asymptomatic hydronephrotic children are unclear. Methods Experimental studies in rats and mice, retrospective studies in children and adults, as well as prospective studies in children are included in this mini review. Results Experimental models of hydronephrosis in rats and mice have demonstrated that partial ureteropelvic junction obstruction (UPJO) is casually linked with development of hypertension and renal injuries in later life. The mechanisms are multifactorial and involve increased activity of the renin–angiotensin–aldosterone system and renal sympathetic nerve activity. Furthermore, oxidative stress and nitric oxide deficiency in the affected kidney appear to play important roles in the development and maintenance of hypertension. Clinical case reports in adults and recent prospective studies in children have associated hydronephrosis with elevated blood pressure, which could be reduced by surgical management of the obstruction. Conclusion Based on current experimental and clinical knowledge regarding the link between partial UPJO and changes in blood pressure, it is proposed that today's non‐operative management of hydronephrosis should be reconsidered to reduce the risk of developing elevated blood pressure or hypertension in later life.