A 17-year-old boy presents with severe hypertension (BP 160/105 mmHg) discovered during a sports physical. Vital signs show HR 88 bpm, RR 16, temperature 37°C. Laboratory studies reveal hypokalemia (K+ 2.9 mEq/L), metabolic alkalosis (HCO3− 32 mEq/L), low plasma renin activity, and suppressed aldosterone level. Urine potassium is elevated. He denies licorice use and takes no medications. Which of the following is the most likely underlying mechanism?
- A)Constitutive activation of epithelial sodium channels in principal cellsGABARITO
- B)Loss of bicarbonate reabsorption in the proximal tubule
- C)Autonomous aldosterone secretion from the adrenal cortex
- D)Inhibition of Na K 2Cl transport in the thick ascending limb
- E)Defective type IV collagen in basement membranes
Explicação
Constitutive activation of epithelial sodium channels in principal cells is correct. Liddle syndrome causes increased sodium reabsorption in the collecting duct, leading to hypertension, potassium wasting, and metabolic alkalosis despite low renin and low aldo... Ver explicação completa e trilha adaptativa →