Acute Kidney Injury

A 58-year-old man with diabetes mellitus type 2 and hypertension presents to the emergency department with acute kidney injury. His serum creatinine has risen from baseline 1.2 mg/dL to 3.8 mg/dL over 48 hours. Urinalysis shows muddy brown casts and fractional excretion of sodium (FENa) is 2.1%. What is the most common cause of acute kidney injury in hospitalized patients in India?

According to KDIGO classification, which of the following defines AKI Stage 2?

A 58-year-old man with diabetes mellitus type 2 and hypertension presents to the emergency department with acute onset oliguria (urine output 0.3 mL/kg/hr) for 8 hours. Serum creatinine has risen from baseline 1.2 mg/dL to 2.8 mg/dL. Urinalysis shows muddy brown casts and granular casts. On examination, he is euvolemic with normal JVP. Blood pressure is 148/92 mmHg. He reports no recent nephrotoxic drug exposure. What is the most appropriate immediate next step in management?

A 52-year-old man with diabetes mellitus type 2 and hypertension presents with acute kidney injury (AKI) stage 2 following contrast-enhanced coronary angiography. Serum creatinine has risen from 1.2 mg/dL to 2.8 mg/dL within 48 hours. He is euvolemic on clinical examination. What is the drug of choice to prevent progression of contrast-induced nephropathy in this patient?

A 72-year-old man with chronic kidney disease (baseline creatinine 2.5 mg/dL, eGFR 22 mL/min/1.73m²) is admitted with acute decompensated heart failure. He is started on intravenous furosemide 80 mg twice daily. On day 3, his serum creatinine rises to 3.8 mg/dL, urine output is 0.5 mL/kg/hr, and serum potassium is 6.2 mEq/L. Urinalysis shows no casts or proteinuria. Renal ultrasound is normal with no obstruction. What is the most appropriate immediate next step in management?