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What is Which of the following is NOT a feature of pre renal azotemia? and explain in detail?
Urine/plasma creatinine (UCr/PCr) will be > 40 in pre renal azotemia. Difference between pre renal and and acute tubular necrosis: Pre renal failure FENa is less than 1% Urine Na is less than 20mmol/l Urine osmolality is more than 500mosm/kg Fractional excretion of BUN is less than 35% BUN/Creatinine ratio is more than 20:1 Acute tubular necrosis FENa is more than 2% Urine sodium is more than 30 mmol/l Urine osmolarity is less than 350mosm/kg BUN/Creatinine ratio is less than 10:1 Ref: Harrisons principles of internal medicine, 18th edition, Page 337