<prompt> Pre-Renal Azotemia is characterized by all of the following, EXCEPT:Fractional Excretion of Na 1Urinary osmolality 500 mosmkgUrinary sodium concentration 40 meq1Reversible with replacement fluids  <response>: Azotemia refers to increase in BUN and creatinine. Azotemia can be prerenal, renal or postrenal. Pre renal azotemia occurs when there is a reduction in the effective aerial blood flow to the kidney, either from a reduction in extracellular volume or in conditions where effective circulating volume is reduced despite normal total extracellular volume. LAB findings include: FeNa is less than 1 ,- proximal tubular function is normal, so it reabsorbs sodium and water, so less sodium is available at the distal tubule leading to greater secretion of renin. This inturn increase aldosterone secretion and increased distal sodium reabsorption resulting in low Fractional excretion of sodium. BUN and creatinine levels are elevated. BUNcreatinine ratio 20:1 as filtered urea is reabsorbed and creatinine is excreted. Urine osmolality is greater than 500mosmlkg. Urine sodium is less than 20meql consistent witjavascript:void 14h normal tubular function. Ref: CURRENT Diagnosis Treatmentchapter, Chapter 9; Advances in clinical chemistry, Volume 29 By Herbe E. Spiegel, Page 137; Nephrology in 30 Days By Robe F. Reilly, Mark A. Perazella, Page 234. 