Renovascular hypertension presenting with hypokalemic metabolic alkalosis.

This report describes two adolescents with severe hypertension secondary to renal artery stenosis who had evidence of a hypokalemic metabolic alkalosis in their initial laboratory evaluation. Hypokalemic metabolic alkalosis is known to occur in approximately 16% of adults with renal artery stenosis but has not been well described in the pediatric literature. It is the result of excess aldosterone secretion stimulated by renal artery stenosis-mediated activation of the renin-angiotension system and by an increase in natriuresis from the contralateral, non-stenotic kidney. Although primary hyperaldosteronism must be considered in children with hypertension and hypokalemia, it is a rare disease in children. This report supports current recommendations that the initial focus of medical investigation in the severely hypertensive child should remain on the kidney.