Since 1995 - Non Profit Healthcare Advice

High Bun/Creatine Ratio

01/08/2009

Question:

I am a 45 yr. old female with 3 ureters. I have had blood in my urine for 2 yrs. unexplained. I recently had a urinary tract infection that took 4 mos. to clear up. I had a ct scan w/wo contrast of my abdomen and pelvis. It showed a small kidney stone in my right kidney. My bloodwork also showed my bun/creatine ratio is high (28). Should I be worried about this high ratio? What should I do?

Answer:

BUN (blood urea nitrogen) and creatinine are waste products that are produced by normal metabolic processes in the body and by the breakdown of foods, especially those high in protein. The normal value for BUN is approximately 10-20, and for creatinine, 0.6-0.9. The ratio between the two is usually between 10:1 and 20:1. However, if BUN is at the high end of normal and/or the creatinine is at the low end of normal, the ratio can actually be high.

Here are some possible explanations:

1) small body size and/or pregnancy: this could make the creatinine level be on the low side.

2) Mild dehydration: after an overnight fast, your body can become a little water-depleted, which could cause the BUN to be on the high side.

3) High protein diet: even a high-protein meal on the day before the test may increase the BUN without affecting creatinine, so that the ratio may become elevated.

If your BUN and creatinine values are both normal, I would not be concerned about a high ratio.  However, if either the BUN or the creatinine is elevated, or if you have protein in your urine, these could be the earliest sign of kidney disease. 

Having three ureters is not uncommon, although it may make you more likely to have an infection.  The stone may explain the small amount of blood in your urine. 

For more information:

Go to the Kidney Diseases health topic.