I recently had some labs done. My BUN was 20, which was slightly higher than its usual 14 or 16. My creatinine level was .67, which also was a fraction lower than a year ago at .71. Those were all within the lab’s normal range. However, my bun-creatinine ratio was 30 and the lab’s normal range tops out at 28. The ratio is higher than it was last year when it was 20. Should I see a doctor? Is the ratio meaningless if the numbers themselves are within normal range, even though they have changed since my last test. My GFR is 95. My A/G ratio is 1.8, which is also in the normal range. I have not had any kidney issues other than kidney stones 20 years ago. I do have primary biliary cholangitis but take medication for that. I have been trying to eat more protein and likely had no liquid other than coffee and a small glass of water on the day of my test. Thank you very much.

A high protein diet will cause a elevated blood urea nitrogen (BUN). This may be the cause of the elevated BUN that you describe. Otherwise, I am unable to make a diagnosis of kidney disease based on the information that you present. The BUN to creatinine ratio is not of any clinical significance.

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