Bun/creatinine levels?

I had my 30 day labwork done and my blood creatnine was low and the Bun/Creatinine ratio was High. Everything else came back perfect. All the doc said was drink more water and test in two weeks.

So of course now I am freaking out with thoughts of kidney failuer!!! Anyone have these issues and did they resolve after time with more water etc?

Not medical here, but I though BUN indicated you might be fighting off a little infection or something.

Don't worry about it too much. Kidney failure would raise your blood creatinine. There are lots of things that result in the BUN Creatinine ratio being high. I suspect it is due to the high protein diet that we eat. See the article I copied below. It is a really good idea to drink lots of water when we eat a high protein diet to help keep the kindeys flushed.

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 0.7-1.2.  BUN and creatinine are excreted by the kidneys and accumulate in the bloodstream when a person has kidney failure.  Therefore, with renal disease, the BUN and creatinine usually both rise together.  However, there are some conditions in which one rises more than the other, and some (as in yours) where one is normal while the other is low.  Here are some possible explanations:

1) Lab error: unless you are a very small woman (with hardly any muscle), or pregnant, or both, a creatinine of 0.5 is unusually low.  Could it be incorrect?  Could the lab have been having a bad day, or did someone miscopy an 0.8 as an 0.5?

2) Dehydration: if you were dehydrated at the time the lab test was done (for example, were having a GI viral illness), the BUN may have increased just due to dehydration (resulting in a high ratio), and should have come back down as soon as you had enough water in your body.

3) Heart failure or liver cirrhosis: both of these conditions can cause a high BUN/creat ratio in the absence of kidney problems.

4) Very high protein diet: a very high protein diet may increase the BUN without affecting creatinine, so that the ratio may become elevated.  (Did you eat a giant steak the night before your blood test?)

5) GI bleeding: if there is a bleeding ulcer or bleeding of any type anywhere in the stomach or intestines, the BUN will rise disproportionately from the creatinine. 

6) Steroids: in people taking high doses of steroid medications such as prednisone, the BUN can be elevated, causing a high calculated BUN/creatinine ratio.

Low blood levels of creatinine are not common, but they are also not usually a cause for concern. They can be seen with conditions that result in decreased muscle mass.



This information is not to be misconstrued as medical advice. You should consult your physician for all medical advice.

How much are you drinking and how much protein are you getting in?  low creatinine can be from not getting in enough protein and dehydration.  Usually the BUN is affected first, I am suprised your BUN isn't high.  The ratio is high because the creatinine is low and the BUN is normal or high.  I would just start drinking more and adding more protein to your diet.  If you add more protein shakes you can kill 2 birds with one stone.