What is creatinine?
Creatinine is a nitrogenous waste product after the normal breakdown of muscles in the body. It is produced in the body through the catabolism of phosphocreatine at a constant rate and is found in the bloodstream. It is part of a cycle that produces energy which is needed in muscle contraction.
How is it relevant to kidneys?
After it has served its purpose, It is filtered by the kidneys and excreted with the urine. Creatinine level is considered as an indication of various kidney diseases. Its normal level depends on your age, race, body size, etc. Men usually have higher creatinine levels than women and children.
How reliable is it?
However, measuring creatinine level alone is not a reliable source to determine whether the body has a kidney problem or not as creatinine level varies considerably according to age, race. body size. Therefore, doctors commend a more authentic and definitive way such as GFR test or Glomerular filtration rate test which is not affected by the varying functions that might mislead the results.
Tests to determine creatinine level:
GFR test is a routine lab test which is found in the blood work report. It helps estimate the rate of blood flow through the kidneys. GFR number gives a fair idea of whether you have kidney disease or not.
Your kidneys are in need of immediate medical attention if your GFR number is –
- Below 60 for three months
- Above 60 with considerable traces of proteins in the urine
Urine test along with the GFR test is mandatory. The urine sample of the patient is collected in a specimen cup and is taken to the lab where the ACR (albumin-creatinine ratio) is calculated determining the amount of albumin in the urine which should not exceed 30 mg/g even if the GFR value is safely above 60. This test also makes it clear how likely it is for the kidneys to get worse which is aptly termed as the risk of progression. Higher amounts of albumin points to a higher risk.
Serum creatinine and creatinine clearance rate :
Creatinine found in the bloodstream is known as serum creatinine. The serum creatinine test is a common blood test with usually no preparations prior to the test. It is part of a routine lab report and higher value indicates that the kidneys are not working properly.
Creatinine clearance, however, is the amount of creatinine found in urine. The creatinine clearance rate is the ability of the kidneys to filter creatinine with the urine. It is yet another test to ensure any irregulation in the kidneys. Generally, all the urine over the time period of 24 hours is collected and the rate of creatinine being filtered is determined.
It is noteworthy that normal and abnormal ranges of creatinine level may vary among labs as they use unique measurements and take different samples. Therefore, it is important that the patient discuss the test results with their doctors and only then decide whether they need further testing or treatment is necessary.
GFR and creatinine clearance rate tests deliver unbiased results which are reliable as well as exact, thus drawing a clearer picture of the situation to work with for the team. You may not undo permanent kidney damage but with appropriate treatment and medical attention, you may be able to prevent any further damage.