ESPE Abstracts

Background: Primary aldosteronism (PA) is a rare form of secondary hypertension. In adults PA is often caused by unilateral adrenal adenoma which can be cured by unilateral adrenalectomy. However, in young patients hereditary causes of PA have to be considered with bilaterally affected adrenal glands.

Objective and hypotheses: We report on an adolescent with PA due to a recently described KCNJ5 mutation and want to point out the importance of performing mutation analysis in pediatric patients with PA.

Method: A 16-year-old boy was referred to our clinic because of hypertension. Diagnostic work up revealed elevated aldosterone and low renin concentrations. A CT scan showed focal thickening of the left adrenal gland, without evidence for a clear adenoma. Adrenal venous sampling did not show lateralisation. Aldosterone was not suppressed by sodium loading which confirmed the diagnosis PA. We performed mutation analysis for CYP11B1/2 and the newly described KCNJ5 mutation.

Results: Mutation analysis was negative for the hybrid CYP11B1/CYP11B2 gene that causes glucocorticoid-remediable aldosteronism but revealed a de novo germline missense mutation in the KCNJ5 gene (c.452G>A (p.Gly151Glu)). This mutation has only been described in seven families causing familial PA type III. Somatic mutations in the KCNJ5 gene are also present in about a third of aldosterone-producing adenomas. In our patient, treatment with an aldosterone antagonist was successful for blood pressure control without surgical intervention.

Conclusion: PA is a rare cause of secondary hypertension, especially in children and adolescents. In hereditary forms of PA bilaterally elevated production of aldosterone can be expected. Therefore, surgery is not the first choice treatment. We recommend mutation analysis for CYP11B2 and KCNJ5 mutation in all children and adolescents with biochemically proven PA.