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What is Decreased fractional excreion of sodium is caused by- and explain in detail?
Ans. is 'a' i.e., Prerenal azotemia Diagnostic IndexPrerenal ARFIntrinsic Renal ARFo Fractional Excretion of NaQ<1>1o trine Sodium ConcentrationQ (mmol/L)<10>20o Urine Creatinine to PlasmaQ Creatinine ratio>40<20o trine osmolalityQ (mosmol/kgH2O)>500-350o Renal failure IndexQ<1>1o Urine urea NitrogenQ to plasma urea Nitrogen>8<3o Plasma BUN/CreatinineQ Ratio>20<10-15o Urinary SedimentQHyaline CastsMuddy Brown Granular Casto Urine Specific gravityQ>1.020~1.010