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Test Code Epic LAB5438 C2 Complement, Functional, with Reflex, Serum

Additional Codes

SQ code C2CMPM

Mayo code C2

Reporting Name

C2 Complement,Functional,w/Reflex,S

Useful 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 Red


Ordering 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

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

86160 x 2 (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
C2 C2 Complement,Functional,w/Reflex,S 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 days

Reject Due To

Gross hemolysis OK
Gross lipemia Reject
Gross icterus OK

Method Name

Automated Liposome Lysis Assay

Secondary ID

81835