[Normal blood pressure and hypertension in the child and adolescent].

The interpretation of hypertension in childhood requires some knowledge of blood pressure characteristics in healthy children. Until puberty no difference between both sexes is observed, but thereafter higher values are found in boys than girls. Blood pressure correlates best with weight, height and age. Repeated measurements demonstrate positive tracking correlations. The tracking phenomenon as well as the familial aggregation of (high) blood pressure form a possible basis for early detection of hypertension prone children. Hypertension is found in 1% of children. However, in the majority of cases (in 80-95%) it is mild and primary, viz. essential hypertension. Secondary hypertension is often severe and usually of renal (or renovascular) origin or is due to coarctation. Newer forms of hypertension are observed in newborns after umbilical artery catheterization, in patients on dialysis or after renal transplantation and in teenagers on oral contraceptives.