Prolidase, Serum or Plasma

What Is Prolidase?

Prolidase is an enzyme that helps break down certain protein building blocks, particularly dipeptides that contain the amino acid proline. This enzyme is important for normal recycling of collagen and for many cellular processes. It is found in tissues throughout the body and small amounts can be measured in blood.

Why This Test Is Ordered

Doctors may order a prolidase level when a person has signs that could suggest prolidase deficiency, a rare inherited disorder. Features can include long-lasting skin ulcers, frequent infections, distinctive facial features, and developmental problems. Testing may also be used to help confirm a suspected diagnosis or to monitor someone known to have the condition.

How the Test Is Performed

This test uses a blood sample, typically drawn from a vein in your arm. The sample is collected into a tube and then sent to a laboratory that measures enzyme activity in serum or plasma. In some cases, testing may also be done on other samples, such as skin cells, but the serum or plasma test is one way to look at prolidase.

What the Results Mean

A low prolidase level can support a diagnosis of prolidase deficiency, while a normal level generally makes that diagnosis less likely. Results are interpreted together with symptoms, family history, and other tests, and sometimes genetic testing is needed to confirm the diagnosis. Because this is a specialized test, your care team will explain what your specific result means for you.