A 58-year-old man with type 2 diabetes mellitus presents to the emergency department with a 3-day history of fever, cough, and dyspnea. On examination, he is hypotensive (BP 88/54 mmHg), tachycardic (HR 118/min), and has bilateral crackles on auscultation. Laboratory investigations show: serum creatinine 3.2 mg/dL (baseline 1.0 mg/dL), BUN 68 mg/dL, urine output 0.3 mL/kg/hr, urine sodium 45 mEq/L, and urine osmolality 320 mOsm/kg. Chest X-ray reveals bilateral infiltrates consistent with pneumonia. What is the most likely type of acute kidney injury in this patient?