In acute tubular necrosis, all are true except: (A) Specific gravity of urine < 1.020, (B) Urine Osmolatlity > 500, (C) Blood urea: creatinine ratio < 20, (D) Urine sodium < 20mmol/l
Answer is D. Acute tubular necrosis: - Muddy brown granular or tubular epithelial cell casts- FENa > 1%- UNa > 20 mmol/L- SG < 1.015 Ref: Harrison's 17/e p1757 table 273-2