Test Code C9 C9 Complement, Functional, Serum
Reporting Name
C9 Complement, Functional, SUseful For
Diagnosis of C9 deficiency
Investigation of a patient with a low total (hemolytic) complement level
Ordering 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.
Specimen Required
Patient Preparation: Fasting preferred
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Immediately after specimen collection, place the tube on wet ice and allow specimen to clot.
2. Centrifuge at 4° C and aliquot serum into a plastic vial.
3. Within 30 minutes of centrifugation, freeze specimen. Specimen must be placed on dry ice if not frozen immediately.
NOTE: If a refrigerated centrifuge is not available, it is acceptable to use a room temperature centrifuge, provided the sample is kept on ice before centrifugation, and immediately afterward, the serum is aliquoted and frozen.
Specimen Type
SerumSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Frozen | 14 days |
Day(s) Performed
Monday through Friday
TAT: 3 - 5 days
Performing Laboratory
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Method Name
Automated Liposome Lysis Assay
Method Description
Complement 9 (C9) activity is measured by mixing patient serum with a C9-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 C9. The target liposomes are a commercial reagent (WAKO total complement CH50), and the assay is performed on an Advia XPT.(Unpublished Mayo method)
Reference Values
37-61 U/mL
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 |
---|---|---|
C9FX | C9 Complement, Functional, S | 87727-4 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
C9FX | C9 Complement, Functional, S | 87727-4 |
Report Available
1 to 3 daysReject Due To
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |