Polycystic Kidney Disease (PKD) is a chronic genetic disease. As the cysts enlarge with age, they will oppress the neighboring kidney tissues thus causing Renal Failure. As kidney has strong sufficient compensatory capacity, the patients do not have symptoms in the early time. Many patients think that if their serum creatinine keeps in the normal range, their renal function must be also normal. In fact, this idea is wrong. Although serum creatinine can reflect the kidney capacity in excreting metabolic wastes and toxins, but it is not sensitive. Only when more than half of patients’ renal function is lost, will the serum level exceed the normal level. The patients with Renal Failure can know their renal function better by the following formula.
Creatinine clearance rate= (140-Age)* body weight (kilogram)*88.4/72*serum
creatinine level (umol/L)
If you are women patients, after you get the above result, you should use it
to multiply 0.85 then you can get your creatinine clearance rate.
The normal creatinine clearance rate should keep within 80~120 ml/minute. The
lower your creatinine clearance rate is, the worse your renal function is.
If your creatinine clearance rate is between 10~15ml/minute, usually your
disease has developed into End Stage Renal Failure. It is not proper for
patients with Renal Failure to judge their renal function just from their
creatinine level. For example, if the two patients have the same creatinine
level: 95umol/L, but other factors are different.
Women patient: 75 years old; 50kilogams
Man patient: 25 years old; 75kilogrmas
From the above formula, we can see that the former patients’ creatinine
clearance rate is 36umol/L and the latter is 111umol/L. Although the former
patient’ renal function has been damaged seriously, but the creatinine level
does not reflect it accurately.
Therefore, the patients with Renal Failure should not judge their renal
function from their creatinine level simply. They should take other indexes in
consideration comprehensively so as to receive effective treatment in the fist