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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Fractional excretion of sodium < 1 is seen in -
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The correct answer is  The fractional excretion of filtered sodium (FENa) has been demonstrated to be a reliably discriminating test between prerenal azotemia and acute tubular necrosis. One paicular urinary index cannot be expected to reliably discriminate between prerenal azotemia and acute renal failure in all cases Prerenal azotemia Oliguria (urine volume < 500 mL/day) or anuria (< 100 mL/day), high urine specific gravity (>1.015), normal urinary sediment, and low urinary sodium (< 20 mEq/L; fractional excretion of sodium < 1%) are seen Ref Harrison20th edition pg 267