When to do the test c

Definition

What is c-peptide?

The C-peptide test measures the level of peptides in the blood. Peptides are usually found in the same amount as insulin, because insulin and C-peptides are bound when they are first produced by the pancreas. Insulin helps the body use and control the amount of sugar (glucose) in the blood. Insulin allows glucose to enter the body's cells which are then used for energy. The level of C-peptide in the blood can indicate the amount of insulin produced by the pancreas. C-peptide does not affect blood sugar levels in the body.

A C-peptide test can be done when diabetes is found, but it is not certain that the type of diabetes you have is type 1 or type 2. A person whose pancreas does not produce insulin (type 1 diabetes) has low levels of insulin and C-peptides. A person with type 2 diabetes has normal or high levels of C-peptide.

A C-peptide test can also help find the cause of low blood sugar (hypoglycemia), such as overuse of drugs to treat diabetes or a non-cancerous growth (tumor) in the pancreas (insulinoma). Because man-made (synthetic) insulin does not have C-peptide, a person with low blood sugar levels from using too much insulin will have low C-peptide levels but high insulin levels. Insulinoma causes the pancreas to release a lot of insulin, which results in decreased blood sugar levels (hypoglycemic). A person with an insulinoma will have high levels of C-peptide in the blood when their insulin levels are high.

When should I take c-peptide?

The C-peptide test can be done for the following reasons:

differentiate the type of diabetes you have, whether type 1 or type 2
to investigate whether you have insulin resistance
to ascertain the cause of hypoglycemia (low blood glucose level)
to monitor insulin production after removal of a pancreatic tumor (insulinoma)

Precautions & warnings

What should I know before taking c-peptide?

A person newly diagnosed with type 2 diabetes often has normal or high levels of C-peptide in the blood. Over time, people with type 2 diabetes can produce low levels of C-peptide.

There are few C-peptide tests performed and may not be readily available in every laboratory. If a series of C-peptide tests are to be carried out, it should be done in the same laboratory and using the same method.

Even though they are produced at the same rate, C-peptide and insulin exit the body via different routes. Insulin is mostly processed and eliminated by the liver, while C-peptide is excreted by the kidneys. Since the lifespan of C-peptides is about 30 minutes compared to insulin which is only 5 minutes, it is not surprising that C-peptides are 5 times more in blood than insulin.

Process

What should I do before taking c-peptide?

You will be asked not to eat or drink (certain fluids) for 8 to 12 hours before the test. If you are taking any blood glucose-lowering drugs, you will usually be asked to stop using this medicine until the test takes place.

How is the c-peptide process?

The medical personnel in charge of drawing your blood will do the following:

wrap an elastic band around your upper arm to stop blood flow. This makes the blood vessel under the bundle enlarge making it easier to insert the needle into the vessel
clean the area to be injected with alcohol
inject a needle into a vein. More than one needle may be required.
Insert the tube into the syringe to fill it with blood
untie the knot from your arm when enough blood is drawn
sticking gauze or cotton on the injection site, after the injection is complete
apply pressure to the area and then put a bandage on

What should I do after taking c-peptide?

An elastic band is wrapped around your upper arm and will feel tight. You may not feel anything when you get the injection, or you may feel like you are stung or pinched.

If you have questions related to this test process, please consult your doctor for a better understanding.

Explanation of the Test Results

What do my test results mean?

Normal scores on this list (called references range) only serves as a guide. Range this varies from laboratory to laboratory, and your laboratory may have different normal scores. How much your lab report will usually contain range they use. Your doctor will also check your test results based on your health condition and other factors. This means if your test results go into range abnormal in this manual, it could be in your laboratory the score belongs to range normal.

The level of C-peptide in the blood should be read with the results of a blood glucose test. These two tests will be carried out at the same time. Tests to measure insulin levels may also be done.

Normal value

Fasting: 0.51-2.72 nanograms per milliliter (ng / mL) or 0.17-0.90 nanomoles per liter (nmol / L).

High marks

High levels of C-peptide and blood glucose are usually found in people with type 2 diabetes or insulin resistance (such as Cushing's syndrome).

High C-peptide levels with low blood glucose levels can indicate the presence of an insulin-producing tumor from the pancreas (insulinoma) or due to the use of certain drugs such as sulfonylureas (for example, glyburide) that cause high C-peptide levels.

If the C-peptide level is high after an insulinoma is removed, this likely means the tumor has returned or the tumor has spread to other parts of the body (metastasized).

Low marks

Low levels of C-peptide and blood glucose can be found in liver disease, severe infection, Addison's disease, or insulin therapy. Low C-peptide levels with high blood glucose levels are found in people with type 1 diabetes.

Removal of the entire pancreas (pancreatectomy) causes the C-peptide level to be so low that it cannot be measured. The blood glucose level will be high, and insulin will be needed for the person to survive.

Depending on your chosen laboratory, the normal range of the C-peptide test may vary. Discuss any questions you have about your medical test results with your doctor.