C3a desArg Fragment Test
This test measures C3a desArg, a fragment formed when the C3 complement component is activated, in a plasma sample. Quest describes elevated levels as reported in several conditions involving immune or inflammatory activation.
About this test
The complement system is part of the body's immune response, and C3 is one of its components. Quest describes this test as measuring the level of C3a desArg, a cleavage product formed when C3 is activated, in plasma.
Quest notes that elevated levels of C3a have been reported in patients with acute lyme disease, acute pancreatitis, systemic lupus erythematosus, and adult respiratory distress syndrome. Because C3a can rise in several different conditions, a single result is read together with a person's symptoms, history and other findings rather than on its own.
Test details
| Collection | Quest patient service center |
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Quest resources
Additional details
What this test looks at
The test reports one value: the level of C3a desArg in plasma. It is a different measurement from a direct C3 protein level, since it reflects a fragment produced only after the complement pathway has been activated.
This test isn't part of the Celio Health store at the moment, so it can't be ordered or requested here. The test menu lists everything that can.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does this test measure?
It measures C3a desArg, a fragment produced when the C3 complement protein is activated, in a plasma sample, using enzyme immunoassay.
How is the sample collected?
The test uses plasma collected in EDTA (lavender-top) tubes, which is then frozen before analysis.
Do I need to prepare for this test?
No preparation instructions are listed for this test, though people follow any instructions their ordering clinician provides.
Why might a clinician look at C3a desArg levels?
Quest notes that elevated C3a levels have been reported in conditions including acute lyme disease, acute pancreatitis, systemic lupus erythematosus, and adult respiratory distress syndrome. A clinician interprets the result in the context of a person's symptoms and other findings.