What Is Plasma Amylase?

Plasma amylase is a measurement of how much amylase, an enzyme produced by the pancreas and salivary glands, is present in the bloodstream. This test may be used as part of a diagnostic workup for a patient with suspected abdominal trauma or kidney disease. It can also be part of follow-up to determine how well a patient is responding to treatment, and to check for transplant rejection in patients who have received donor kidneys. The test is minimally invasive and comes with low risk for the patient.

To determine plasma amylase values, it is necessary to take a small blood sample and send it to a lab. Elevated levels of the enzyme indicate that something is wrong, and the patient may be in need of medical attention. Reference ranges can depend on the lab and the equipment it uses; the lab typically notes its reference ranges on test results for the benefit of medical professionals. Patients who are tested at two different labs may have variable results.

When the kidneys are inflamed, stressed as a result of trauma, or not functioning properly because of disease, amylase levels can be elevated. This can be seen in patients with issues like alcoholism and kidney infections, as well as in some people who have recently been in car accidents. Conditions like congestive heart failure can also lead to elevated plasma amylase because they cause organs to slowly shut down over time. In a patient with unexplained abdominal pain, a blood test to check for this enzyme and other markers may be recommended to rule various causes in or out.

Patients receiving treatment for a specific issue may receive a follow-up plasma amylase test to see if they are responding. The levels should drop over time, indicating that kidney function is improving. If the kidneys don’t get better, another course of treatment may need to be considered to address the problem. For transplant patients, regular checks on kidney function are critical to confirm that the donor organ is working right, without issues like rejection or inflammation that might cause problems for the patient.

Results on a plasma amylase test may take varying lengths of time depending on the facility and the level of busyness at the lab. Patients who want to learn more about their results can ask for an explanation of this and other levels on the lab test. In the event the plasma amylase is unexpectedly high, the doctor may want to order more tests and take a more detailed patient history to find out why.