Aldosterone, Plasma Renin Activity, and Aldosterone/Renin Ratio in a Normotensive Healthy Pediatric Population

Primary aldosteronism is an important cause of secondary hypertension and is suspected in adults with an aldosterone/renin ratio > or =25. The normal aldosterone/renin ratio is unknown in children. The aim was to establish serum aldosterone, plasma renin activity, and aldosterone/renin ratio values in a healthy pediatric population. A cross-sectional study was performed in 211 healthy normotensive children (4 to 16 years old). Two subgroups of normotensive children were obtained: with hypertensive parents (NH) (n=113) and normotensive parents (n=98). Blood samples for measuring serum aldosterone, plasma renin activity, aldosterone/renin ratio, and DNA were collected. In subjects with aldosterone/renin ratio > or =25, the chimeric CYP11B1/CYP11B2 gene was investigated by long-extension PCR. Results are expressed as median Q(1)-Q(3). NH and normotensive parents groups were similar in serum aldosterone (6.5 3.6 to 9.0 ng/dL versus 6.5 2.9 to 9.7 ng/dL; P=0.968) and plasma renin activity (2.3 1.6 to 3.1 versus 2.4 1.7 to 3.7 ng/mL per hour; P=0.129). The aldosterone/renin ratio was higher in the NH group, but this difference did not reach statistical significance (2.8 1.9 to 4.1 versus 2.5 1.4 to 4.0, P=0.104). In one subject of the NH group, the chimeric CYP11B1/CYP11B2 gene was detected. We demonstrated that normal aldosterone/renin ratio values in a healthy pediatric population without NH were lower than those reported for an adult normotensive population.