A 52-year-old man with a history of hypertension presents with a 3-day history of productive cough, fever, and dyspnea. Chest imaging confirms pneumonia. On admission, his blood pressure is 88/52 mmHg, and he is started on broad-spectrum antibiotics, aggressive intravenous fluid resuscitation (6 liters over 12 hours), and norepinephrine. Despite these interventions, urine output decreases to 0.3 mL/kg/hr. Laboratory studies at 48 hours show: serum creatinine 3.5 mg/dL (baseline 0.9 mg/dL), BUN 68 mg/dL, urine osmolality 285 mOsm/kg, urine sodium 65 mEq/L, and fractional excretion of sodium (FENa) 3.2%. Urinalysis shows muddy brown casts. Which of the following best explains his acute kidney injury?
- A)Prerenal acute kidney injury from persistent hypoperfusion despite fluid resuscitation
- B)Postrenal acute kidney injury from acute urinary retention
- C)Acute tubular necrosis from sepsis-induced renal hypoperfusion and ischemiaGABARITO
- D)Acute interstitial nephritis from antibiotic-induced hypersensitivity reaction
- E)Rhabdomyolysis-associated acute kidney injury from critical illness myopathy
Explicação
This patient has acute tubular necrosis (ATN) from sepsis-induced renal ischemia. The key diagnostic findings are: (1) FENa 3.2% (>2%, indicating intrinsic renal damage); (2) low urine osmolality (285 mOsm/kg, indicating tubular dysfunction); (3) muddy brown c... Ver explicação completa e trilha adaptativa →