Ulcerative colitis is based on biopsy during colonoscopy.
It is a pathological diagnosis.
So it would not be possible to discount this and "not agree" with a pathological diagnosis.
Colitis is not caused by kidney dysfunction.
However, chronic renal failure can cause diarrhea, along with many other symptoms.
If you still have an elevated creatinine, at all, this is a serious problem in and of itself.
In addition, kidney stones, and inflammation of the kidney can be associated
with ulcerative colitis, as complications of the disease.
This would be far more likely than a kidney problem causing colitis.
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