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Renal Diet Plans, Reviews, Tips & Advice
Creatinine is a substance produced in the muscles by metabolism. It's a waste product
filtered from the blood by the kidneys. When creatinine levels in the blood are tested
as lower than normal, this is (in part) a sign that the kidneys are functioning well,
or at least, unlike elevated creatinine, not a sign to the contrary. Elevated creatinine
is a reason for concern. Low creatinine levels normally are not, at least not without
other diagnostic indications. All of this applies to serum (blood) creatinine levels
taken in isolation. Of much greater importance is the ratio of serum creatinine to
creatinine in urine.
While low creatinine levels in the blood are actually a good sign most of the time, low creatinine levels in urine can be a bad one. The kidneys filter this waste product from the blood and put it into the urine, so we should expect urine creatinine levels to be higher than blood creatinine levels. Contnued below....
A low creatinine level in urinalysis combined with elevated creatinine in the blood shows at least partial renal dysfunction which can be a serious condition. However, low urine creatinine levels by themselves can simply show that low levels of creatinine are being produced by the metabolism for any of the reasons mentioned above.
The important indicator is elevated creatinine in the blood, rather than low creatinine in the urine; however, the two together do help to pinpoint the problem as arising in the kidneys rather than elsewhere.
In fact, the important consideration is not either test in isolation so much as the
relationship between the two. When creatinine levels in the blood are higher than
in the urine, that is an indication of a disorder of the kidney and requires further
investigation with additional diagnostic procedures to determine the source and nature
of the disorder.
Women on the average have lower muscle mass than men, and therefore produce less creatinine. Creatinine levels in the blood are normally lower for women than for men. What this means in practice is that a lower baseline level of blood creatinine is used for women than for men.
A serum creatinine level that would be considered "low" for a man is considered normal
in a woman. In addition, those of African descent have higher normal serum creatinine
levels than those of non-
Children also have lower muscle-