Arterielle Hypertonie bei pädiatrischen Nierenerkrankungen

High blood pressure (arterial hypertension) in childhood must be diagnosed and treated early to prevent later cardiovascular morbidity and mortality. Children with chronic kidney disease (CKD) are a particularly vulnerable group. The decline of kidney function via activation of the renin-angiotensin-aldosterone system (RAAS) leads to arterial hypertension at an early stage, which is aggravated by the progression of renal insufficiency with restricted diuresis and volume overload. The high blood pressure in turn not only damages the blood vessels and the heart but also the kidneys, thus creating a vicious circle. Standardized blood pressure measurement and ambulatory blood pressure monitoring are important cornerstones for diagnosing arterial hypertension and during follow-up examinations. For both modalities, sex, age and height-adjusted reference values must be used up to the age of 16 years. In the context of CKD, pharmacological antihypertensive treatment is necessary. RAAS blockade with either angiotensin-converting enzyme (ACE) inhibitors or angiotensin II type 1 (AT1) receptor antagonists is the treatment of choice due to the nephroprotective and anti-proteinuric properties. In general, a blood pressure target below the 90th percentile is recommended. Based on an interventional study that showed a significant attenuation in the progression of renal insufficiency with more intensive blood pressure control, blood pressure in children with CKD should be < 75th percentile and < 50th percentile in the case of proteinuria. For children on kidney replacement therapy, especially after kidney transplantation, blood pressure targets are less clear as evidence from interventional studies is still in the making. For long-term care, monitoring of end-organ damage by regular echocardiography, fundus examination and checking for albuminuria is essential.