A 23-year-old woman presents with fatigue and recurrent nephrolithiasis. Vital signs show BP 128/82 mmHg, HR 88/min, RR 16/min, temperature 37°C. Laboratory studies reveal normal anion gap metabolic acidosis with pH 7.32, serum potassium 3.1 mEq/L, and urine pH 6.0 despite systemic acidosis. Serum calcium is elevated at 10.8 mg/dL. Urinalysis shows no hematuria. Which of the following is the most likely underlying defect?

  1. A)Decreased aldosterone effect in the collecting duct
  2. B)Increased chloride reabsorption in the thick ascending limb
  3. C)Excess ammonia generation in the proximal tubule
  4. D)Impaired hydrogen ion secretion in alpha intercalated cellsGABARITO
  5. E)Impaired bicarbonate reabsorption in the proximal tubule

Explicação

Impaired hydrogen ion secretion in alpha intercalated cells is correct. Distal or type 1 renal tubular acidosis results from failure of distal acid secretion, leading to an inappropriately high urine pH, hypokalemia, and increased risk of calcium phosphate sto... Ver explicação completa e trilha adaptativa →

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