BUN and Creatinine

[chihep]

Hi all,
Has anyone experienced low BUN and creatinine blood test? How is it common in people who have cirrhosis?

All feedback would be appreciated.
Thank you,

[fntn]

Have your labs stabilized? And have your doctor's done any micro-anaylisis of your urine? In particular, they will see casts (usually tubular) as your kidneys get damaged by the disturbed portal blood flow. This is basically internal filtering parts of your kidneys breaking down and entering the blood, easily seen and this helps the doctors track down the hepatorenal syndrome progression.

[flyinlynn]

What does you gastroenterologist say?

[chihep]

My BUN and creatinine level have dropped to lower than normal range. I have read that it is rare but seen in severe liver damage. In this case, GFR is not reliable for renal function. Worried! Seems no one experienced.

[HectorSF]

Only your doctor knowing your history and test result can determine if there is anything to be worrying about. Talk with your doctor so you can determine what is going on.

Changes in BUN and creatinine would rarely be the signs of advanced liver disease. There would be many other signs of liver disease before the kidney function would be effected. Kidney issues are usually only seen in advanced decompensated cirrhosis when the liver failure begins to cause kidney failure as well.

Good luck to you.
Hector

[fntn]

Hector is correct, as always. I went through the HRS myself, and my numbers were very high, unlike yours. So hopefully you remain healthy!

[HectorSF]

The blood urea nitrogen or BUN test is primarily used, along with the creatinine test, to evaluate kidney function. Those with advanced cirrhosis may have an impact on kidney function as their liver function progressively fails. This is why the creatinine level is one the the blood tests that make up the MELD score that determines the need for liver transplantation.

Typically when a patient experiences Hepatorenal Syndrome as a result of cirrhosis a HIGH creatinine level is seen.
(Low glomerular filtration rate, indicated by serum creatinine level > 1.5 mg per dL (130 μmol per L) or creatinine clearance < 40 mL per minute (0.67 mL per second).

Like many other complications arising from cirrhosis, kidney issues are the result of the portal hypertension that is the result of the scarring of the liver causing abnormalities in normal blood flow around the liver. In this case effecting the kidneys.

Renal failure is a very common, severe complication  in  patients  with  decompensated  cirrhosis and is a risk factor for a poor outcome of liver transplantation.  Recently  introduced  therapies have demonstrated efficacy in t he prevent ion and management  of  the  hepatorenal  syndrome,  a particularly severe form of renal failure characteristic of cirrhosis. Use of these therapies in patients  awaiting  liver  transplantation  may  help improve the outcome after transplantation.

Luckily liver transplant doctors are very experienced with these issues and are very good at determining which people may need a liver AND kidney transplant and those who kidneys will "bounce back" once a new fully functioning liver is transplanted in the recipient.

Please talk to your liver doctor (gastroenterologist or hepatologist) to learn more about what these tests results may mean in the context of your health and liver disease.

Hector