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HelpOrder Code LAB1897 C2 Complement, Functional, with Reflex, Serum
Reporting Name
C2 Complement,Functional,w/Reflex,SUseful For
Investigation of a patient with a low (absent) hemolytic complement, with reflex testing to C3 and C4, if appropriate
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| C4 | Complement C4, S | Yes | No |
| C3 | Complement C3, S | Yes | No |
Testing Algorithm
If the C2 result is less than 15 U/mL, then complement C3 and C4 will be performed at an additional charge.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
Serum RedOrdering Guidance
This test is for assessment of complement C2 and includes assessment of C3 and C4 as reflex testing. Unless a deficiency has already been identified, initial assessment should begin with the total complement assay (COM / Complement, Total, Serum), which is a screen for suspected complement deficiencies and should be performed before ordering individual complement component assays. A deficiency of an individual component of the complement cascade will result in an undetectable total complement level.
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
CPT Code Information
86161
86160 x 2 (if appropriate)
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liposomes are a commercial reagent (WAKO total complement CH50) and the assay is performed on a Siemens Advia XPT.(Unpublished Mayo method)
Reject Due To
| Gross hemolysis | OK |
| Gross lipemia | Reject |
| Gross icterus | OK |
Method Name
Automated Liposome Lysis Assay