Creatinine Test

Muscles help in the movement of our bodies, but they need creatine to function, which is an organic acid that supplies energy to cells. When it breaks down, creatinine is produced as a waste by-product. It is then carried to the kidney via blood. This creatinine later tells physicians whether or not our kidneys are working properly.  

Improper functioning of kidneys is shown by symptoms like fatigue, loss of appetite, lower back pain, change in the amount and frequency of urine, nausea, and vomiting. The consulting doctor will ask you to check the creatinine levels, which are tested through a creatinine test. And the test tells the doctors whether the kidneys are working properly.

High levels of creatinine show the kidney is not working properly. It can be due to bacterial infection, kidney stones, diabetes, or dehydration.

The creatinine test is also performed as a part of other tests like the Blood Urea Nitrogen (BUN) test, Kidney function test and Basic Metabolic Panel (BMP).

Other Names of Creatinine Test

• Blood Creatinine
• Serum Creatinine
• Creatinine test as part of Basic Metabolic Panel (BMP)
• Creatinine test as part of Comprehensive Metabolic Panel (CMP)

What does the test detect/measure, and who is this prescribed for?

The creatinine test measures the amount of creatinine in the blood.

The abnormal levels of creatinine indicate there is some problem with the kidneys. The body will show symptoms of kidney damage like:

• Change in the amount, appearance and frequency of urine
• Nausea
• Chest pain
• Vomiting
• Cramps in muscles
• Swelling in face, ankles, wrist and stomach
• Fatigue
• Loss of appetite
• Itchiness
• Pain in the lower back

The consulting physician will prescribe the creatinine test if the person shows such symptoms along with other signs of kidney damage or to check the level of fitness before surgery or any procedure, like a CECT scan.

Some disease conditions for which a creatinine test is prescribed are:

• Malnutrition
• Dehydration
• Diabetes
• High blood pressure
• Chronic kidney disease
• Kidney stones
• Prostate disease
• Glomerulonephritis
• Bacterial infection in kidney
• Congestive heart failure
• Pregnancy
• Family history of kidney disease
• Procedures like CECT
• Check  fitness for surgery

In the above-mentioned conditions, creatinine level is measured along with other parameters. Once doctors arrive at a diagnosis, they begin the treatment. The doctors may prescribe the creatinine test at regular intervals to assess kidney health and the effect of treatment.

The creatinine test is also prescribed as a routine physical test in healthy adults. It is examined in the basic metabolic panel. The test also helps in the early detection of kidney damage. Therefore, it is also prescribed for screening kidney disease.

The creatinine test is suitable for all men and women. Some medications can interfere with the results of creatinine test results. If you are taking any medicine, ask your doctor about it.

A simple venous blood sample is sufficient to test blood levels of creatinine. The creatinine levels are detected in the serum, which is a component of the blood.

Test Preparation

The creatinine test does not require fasting or any specific preparation. The serum creatinine level is measured by using a blood sample. It is collected through a prominent vein of the forearm using a needle or syringe. The collected blood is sent to a laboratory for results.

Test inclusions: What parameters are included?

The creatinine test considers the following parameters:

• The value of creatinine in the blood. It is expressed as milligrams per deciliter (mg/dL) of blood.
• The result of the creatinine test is expressed as normal, high or low. High levels indicate the improper working of kidneys due to some underlying health conditions. A low level indicates malnutrition or muscle loss.

Glomerulitis, Kidney stones, Prostate disease, Chronic Kidney Disease(CKD)

The reference range for serum creatinine level is:

• For children 3 to 18 years of age, the normal serum creatinine level is 0.5-1.0mg/dL.
• The creatinine level range may vary but typically lies between the above-mentioned values.
• The creatinine value also depends upon age, race, and body mass.
• Women have lower creatinine levels due to less muscle mass.
• Pregnant women may have abnormal levels of creatinine due to some complications.

The normal values, parameters, and reference ranges of the test may vary from lab to lab. Please refer to the ranges mentioned in the report and consult a doctor to understand the interpretation of lab reports.

The results of the creatinine test depend upon many factors like age, diet, body weight, muscle mass, and even race. The consulting doctor can guide you better with the results in your specific context. The test interpretation will also depend upon the symptoms for which you took the test.

Interpretation of serum creatinine test:

Normal- The serum creatinine level is between the range of 0.9-1.3 mg/dL for adult males and 0.6-1.1mg/dL for adult females.

A high level of creatinine is seen in certain conditions like:

• High blood pressure
• Diabetes
• Dehydration
• Complications in pregnancy
• Infections in kidney
• Kidney stones
• Urinary tract infection
• Prostate disease
• Consumption of large amounts of meat.
• Certain medications like ibuprofen and aspirins
• Chronic kidney disease
• Autoimmune conditions like lupus nephritis

The low level of creatinine is seen in certain conditions like:

• Low muscle mass
• Old age
• Malnutrition
• Bed-bound patients or those who have been ill for a long time.

Any abnormal level of creatinine is not a problem in itself. Instead, it shows there is some other problem that needs to be diagnosed and treated. Low levels of creatinine are not considered any serious health issue, but high levels are a matter of concern.