Concurrent Activation of Renin-Angiotensin-Aldosterone and Hypothalamic-Pituitary-Adrenal Systems for a Two-Month-Old Infant: A Rare Pediatric Endocrine Case Report

Abstract

Laboratory investigations showed concurrent activation of the renin-angiotensin-aldosterone system (RAAS) and hypothalamic-pituitary-adrenal (HPA) in a two-month-old boy infant. Plasma renin was found to be markedly elevated (374.00 uIU/mL; reference: 4.4–46.1 uIU/mL), serum aldosterone was found to be markedly elevated (93.2 ng/dL; reference: 2.52–39.2 ng/dL), serum cortisol was found to be low normal (154.80 nmol/L; reference: 171–536 nmol/L) and plasma ACTH was found to be markedly elevated (185.50 pg/mL; reference: 6–58 pg/mL). This hormonal pattern raises concern for congenital adrenal hyperplasia (CAH), primary or secondary adrenal insufficiency with compensatory RAAS activation, or a concomitant disorder affecting both axes. This case illustrates the diagnostic challenge of dysregulation of the adrenal and renal axis in early infancy.