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HelpTest Code C2 Func C2 Complement, Functional, Serum
Reporting Name
C2 Complement, Functional, S, NRClinical System Name: C2 Complement, Functional
Useful For
Investigation of a patient with a low (absent) hemolytic complement
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
Serum RedOrdering Guidance
The total complement assay (COM / Complement, Total, Serum) should be used as a screen for suspected complement deficiencies before ordering individual complement component assays. A deficiency of an individual component of the complement cascade will result in an undetectable total complement level.
To evaluate for complement C2, C3, and C4 in one orderable, consider ordering C2 / C2 Complement, Functional, with Reflex, Serum.
Specimen Required
Patient Preparation: Fasting preferred but not required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Collection Container/Tube: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Immediately after specimen collection, place the tube on wet ice.
2. Centrifuge and aliquot serum into plastic vial.
3. Immediately freeze specimen.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum Red | Frozen | 21 days |
Reference Values
25-47 U/mL
Day(s) Performed
Monday through Friday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86161
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| C2FXN | C2 Complement, Functional, S, NR | 93977-7 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| C2FX | C2 Complement,Functional,S | 93977-7 |
| INT53 | Interpretation | 69048-7 |
Method Description
C2 complement activity is measured by mixing patient serum with a C2-deficient serum. The lytic activity of the serum mixture is tested against sensitized, labeled liposomes. If lysis occurs, the patient serum must be the source of the C2. The target liposomes are a commercial reagent (WAKO total complement CH50), and the assay is performed on a Siemens Advia XPT.(Unpublished Mayo method)
Report Available
1 to 3 daysReject Due To
| Gross hemolysis | OK |
| Gross lipemia | Reject |
| Gross icterus | OK |
Method Name
Automated Liposome Lysis Assay