High Creatinine in Dialysis Patient

“I am on dialysis, but why do I still have high creatinine level?” Many patients undergoing dialysis have this kind of doubt. Here we will explain it in detail.
Firstly, you should know why you have to go on dialysis and what the function of this treatment is.
No matter what caused your kidney disease and which kind it belongs to, the result is the same: your kidneys will gradually lose their function and failed to finish their task. This is called end-stage renal disease (ESRD). Generally, the options for this stage is either dialysis or kidney transplant. Here we just talk about dialysis.
How does dialysis help to treat your kidney failure? Actually, dialysis is not “treating” your kidney failure at all—it just take the place of the kidneys to perform the functions that should have been done by the kidneys. When the kidneys have lost most of their functions, dialysis is needed to help your kidneys to filter your blood and clean the metabolic wastes.
Secondly, why you still have high creatinine level after the dialysis treatment?
We have explained that dialysis is just a replacement therapy of kidney failure. You have to do dialysis regularly because your body is continuously producing metabolic wastes, which must be cleared out from time to time. Creatinine is just one of the metabolic products.
Creatinine is the waste product of protein metabolism. Derived from creatine and synthesized in liver, kidneys and pancreas and stored in muscle tissue. Creatinine is released into the extracellular fluid and excreted through the kidneys. Creatinine is filtered by the glomeruli and NOT reabsorbed. When kidneys are working properly, serum creatinine level is low but with renal function impaired, creatinine level increases. If half of nephrons are damaged then serum creatinine level rises to about double.
During dialysis, your creatinine would have a fluctuation. When you have just finished the dialysis, your creatinine level would go down because creatinine in your blood has been cleaned out by the dialysis. Therefore, creatinine does not really go down during dialysis (meaning while on dialysis not actually while on the machine during a run). Creatinine doesn't go down basically because labs are usually taken before a dialysis session so you can get an idea of where the body is at; if it was taken right after a dialysis session it would be artificially lower, because the toxins would be removed. Anyway since the creatinine is just a measure of the toxins in the blood and the kidneys aren’t doing their job it will remain high, reflecting the fact that toxins are building up between dialysis sessions(and hence the need for dialysis). Once on dialysis the creatinine measure is mostly irrelevant anyway since the renal function is gone anyway.
Another factor is that different kinds of dialysis have different effect. The two basic types of dialysis are hemodialysis and peritoneal dialysis. Compared with hemodialysis, peritoneal dialysis can lower the creatinine to a smaller degree. That is to say, your creatinine can be lowered by peritoneal dialysis not as much as hemodialysis.
Normal creatinine level (for reference):
Men = 0.6~1.5 mg/dL
Women = 0.6~1.1 mg/dL
Pregnancy = reduced in children = 0.2~1.0 mg/dL
That’s all for high creatinine level in patients undergoing dialysis.