Creatinine Test

Serum creatinine test is used to measure the levels of creatinine in your blood.

What is Creatinine?

Creatinine is a waste product from the breakdown of creatine found in your muscle. This test is performed to see how well your kidneys are working.

Each kidney is made up of tiny blood-filtering structural units called nephrons. The nephrons filter blood constantly through a very small cluster of blood vessels called glomeruli. These filter waste products, excess water, and impurities of blood. These toxins are stored in the bladder and removed through urination. Creatinine is eliminated through kidney from our body. Hence measuring the level of creatinine in the blood indicate your kidney function. High levels of creatinine in blood show kidney impairment.

Why this test is recommended?

This test may be recommended to you as a part of your regular medical checkup. It is usually given with routine blood tests. Your doctor may recommend this test to you if you have signs and symptoms like less appetite, swelling of feet and ankle, dry itchy skin, puffy eyes, frequent tiredness, muscle cramps, frequent or painful urination, blood or protein in the urine, etc.

Factors like age, gender, race, health history and glomerular filtration rate (GFR) are also considered in measuring the functioning of the kidney. Usually, blood urea nitrogen (BUN) is also done along with your serum creatinine test.

Creatinine level depends on the muscle mass you have. It varies in men, women and children depending on their age. Your test results may not always indicate a problem with your kidney. Ask your healthcare provider about your results.

Precaution:

Some factors might affect the results of your serum creatinine test like having a lot of meal before the test, administering large doses of vitamin C, pregnancy, taking certain medicines like antibiotics (trimethoprim, cephalexin, cefuroxime), cimetidine, ranitidine, famotidine, aspirin, ibuprofen, chemotherapy medications, etc. Hence inform your doctor or technician about all your current medications and medical conditions prior to the test.

If the serum creatinine levels are more than the normal level then it may indicate kidney disease, obstruction in your urinary system, congestive heart failure, dehydration, diabetes, shock, overactive thyroid gland, problems during pregnancy like such as seizures due to eclampsia or high blood pressure caused by preeclampsia etc.

If the serum creatinine levels are less than the normal level then it may be due to severe liver disease, muscle loss, not enough protein in your diet, etc.

If you get abnormal test results consult your doctor immediately. Your doctor may recommend other tests depending on your results.