A 63-year-old man with long-standing diabetes mellitus presents for routine follow-up. Vital signs: BP 142/88 mmHg, HR 76/min, RR 16/min, temp 37.2°C. He takes lisinopril daily. Laboratory studies show potassium 5.9 mEq/L, bicarbonate 18 mEq/L, chloride 112 mEq/L, normal anion gap, and creatinine 2.8 mg/dL. Urinalysis shows 2+ proteinuria but no hematuria. Which of the following is the most likely cause of these abnormalities?
- A)Vomiting with extracellular fluid contraction
- B)Hypoaldosteronism causing impaired distal potassium and hydrogen secretionGABARITO
- C)Excess distal hydrogen secretion by alpha intercalated cells
- D)Loop diuretic induced chloride depletion
- E)Defective proximal bicarbonate reabsorption with phosphaturia
Explicação
Type 4 renal tubular acidosis is due to hypoaldosteronism or aldosterone resistance and is common in diabetic nephropathy. It produces hyperkalemia and a normal anion gap metabolic acidosis because the distal nephron cannot appropriately secrete potassium and ... Ver explicação completa e trilha adaptativa →