Need help with BUN/Creatinine

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Need help with BUN/Creatinine

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7 Posts

huzefa
Forum Junior

Topics: 2
Posts: 66

03/26/06 - 08:16 PM

I'm kind of confused regarding the BUN/Creatinine ratio. Which is higher in Prerenal vs. Postrenal vs. Kidney problems? What does the a high or low ratio mean? Thanks

H

sosikan
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Topics: 3
Posts: 78

03/27/06 - 07:16 AM

prerenal BUN/cre =biger than 15/1
renal BUN/cre=10/1

docarchana
Forum Guru

Topics: 70
Posts: 515

09/02/06 - 08:54 PM

postrenal BUN/C > 15

suv
Forum Elite

Topics: 43
Posts: 233

09/02/06 - 10:06 PM

from FA prerenal renal postrenal
Urine osmolarity >500 <350 <350
urine Na <10 >20 >40
fractional excretion of Na <1% >2% >4%
BUN/cr ratio >20 <15 >15

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study_ing
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09/04/06 - 01:26 PM

remember in prerenal azotemia, reanal fx itself is intact. the problem is inadequate perfusion.

hence the kidney tries to preserve more fluid too. urea is filtered and reabsorbed. in this case gfr is low hence filtration is less too.however PASSIVE reabsorption is GREATER( . hence urea levels rise significantly.

Creatinine is filtered and to a lesser extent secrweted. it is affected less tahn ures.

thus in prerenal azotemia, bun / cr ratio wud be higher.

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docarchana
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09/04/06 - 02:56 PM

thanx studying. now i got it.

study_ing
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09/04/06 - 03:03 PM

no problem at all

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