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HelpTest Code FC4AL C4 Level by RIA
Additional Codes
| Test Name in EPIC | EPIC Test Code | Mnemonic | Mayo Test ID |
| C4A LEVEL | LABC4A | FC4AL | FC4AL |
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Container/Tube: Lavender top (plasma gel tubes are not acceptable)
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL plasma
Collection Instructions:
1. Mix well.
2. Within 30 minutes of collection (preferably immediately after venipuncture), centrifuge at ambient temperature, aliquot 1.5mL of plasma into a plastic vial and freeze immediately on dry ice or at -60 C or below in an ultra-low freezer.
3. Ship frozen.
Method Name
Radioimmunoassay (RIA)
Reporting Name
C4a LevelSpecimen Type
Plasma EDTASpecimen Minimum Volume
Plasma: 0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Plasma EDTA | Frozen | 365 days |
Reject Due To
| Hemolysis | Mild OK; Gross reject |
Reference Values
0-2830 ng/mL
Performing Laboratory
National Jewish HealthTest Classification
The performance characteristics for this test have been validated by National Jewish Health. It has not been cleared or approved by the U.S. Food and Drug Administration. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. This laboratory is certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88) as qualified to perform high complexity clinical laboratory testing.CPT Code Information
86160
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| FC4AL | C4a Level | Not Provided |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| FC4AL | C4a Level | Not Provided |
Day(s) Performed
Monday through Friday
Report Available
9 to 14 daysClinical Information
The complement system is part of our innate immune response. It is vital to our defense against invasive microorganisms. Complement activation can occur through the classical, lectin and alternative pathway, which then converge to a common terminal pathway. Activation of the complement pathway(s) results in the generation of biologically active peptides, also known as complement split products, and referred to as anaphylatoxins (C4a, C3a, C5a) which protect us from invasive microorganisms by enhancing inflammation, facilitating the clearance of immune complexes and apoptotic cells, enhancing cellular and antibody immune responses and altering vascular permeability, as well as smooth muscle contractility.
The anaphylatoxin C4a can be elevated above normal levels in many conditions associated with inflammation, including chronic fatigue syndrome, multiple sclerosis, immune complex diseases such as antiphospholipid syndrome and autoimmune conditions such as lupus. C4a is also an early marker of acute Lyme disease.
Interpretation
Elevated C4a levels are indicative of classical and/or lectin pathway activation.