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25519 C2 Complement, Functional, with Reflex, Serum (C2)

C2 Complement, Functional, with Reflex, Serum (C2)
Test Code: C2SO
Synonyms/Keywords
C2 Functional
Test Components

If the C2 result is <15 U/mL, then complement C3 and C4 will be performed at an additional charge.

Useful For
The investigation of a patient with a low (absent) hemolytic complement (CH50), with reflex testing to C3 and C4, if appropriate.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
 Fasting preferred, but not required ​Serum ​Red Top Tube (RTT) ​1 mL ​0.5 mL
Collection Processing 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 Stability Information
Specimen Type Temperature Time
Serum​ ​Frozen ​21 days
Rejection Criteria
Gross lipemia
Interference
As with all complement assays, proper sample handling is of utmost importance to ensure that the complement system is not activated before clinical testing.
 
Absent (or low) C2 functional levels in the presence of normal C2 antigen levels should be replicated with a new serum specimen to confirm that C2 inactivation has not occurred during shipping.
Performing Laboratory Information
Performing Location Day(s) Test Performed Report Available Methodology/Instrumentation
Mayo Clinic Laboratories​ ​Monday through Friday ​1 to 2 days ​Automated Liposome Lysis Assay
Reference Lab
Reference Range Information
Performing Location Reference Range
​Mayo Clinic Laboratories ​25 - 47 U/mL
Interpretation

Low levels of complement may be due to inherited deficiencies, acquired deficiencies, or due to complement consumption (eg, as a consequence of infectious or autoimmune processes).

Absent (or low) C2 levels in the presence of normal C3 and C4 values are consistent with a C2 deficiency.

Low C2 levels in the presence of low C3 and C4 values are consistent with a complement-consumptive process.

Low C2 and C4 values, in the presence of normal values for C3 is suggestive of C1 esterase inhibitor deficiency.

Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
86161​ ​1
​86160 ​2 ​If needed
Synonyms/Keywords
C2 Functional
Test Components

If the C2 result is <15 U/mL, then complement C3 and C4 will be performed at an additional charge.

Ordering Applications
Ordering Application Description
​COM ​C2 Complement w/Reflex
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)
Pediatric Minimum Volume
(no repeat)
 Fasting preferred, but not required ​Serum ​Red Top Tube (RTT) ​1 mL ​0.5 mL
Collection Processing

1. Immediately after specimen collection, place the tube on wet ice.

2. Centrifuge and aliquot serum into plastic vial.

3. Immediately freeze specimen.

Specimen Stability Information
Specimen Type Temperature Time
Serum​ ​Frozen ​21 days
Rejection Criteria
Gross lipemia
Interference
As with all complement assays, proper sample handling is of utmost importance to ensure that the complement system is not activated before clinical testing.
 
Absent (or low) C2 functional levels in the presence of normal C2 antigen levels should be replicated with a new serum specimen to confirm that C2 inactivation has not occurred during shipping.
Useful For
The investigation of a patient with a low (absent) hemolytic complement (CH50), with reflex testing to C3 and C4, if appropriate.
Test Components

If the C2 result is <15 U/mL, then complement C3 and C4 will be performed at an additional charge.

Reference Range Information
Performing Location Reference Range
​Mayo Clinic Laboratories ​25 - 47 U/mL
Interpretation

Low levels of complement may be due to inherited deficiencies, acquired deficiencies, or due to complement consumption (eg, as a consequence of infectious or autoimmune processes).

Absent (or low) C2 levels in the presence of normal C3 and C4 values are consistent with a C2 deficiency.

Low C2 levels in the presence of low C3 and C4 values are consistent with a complement-consumptive process.

Low C2 and C4 values, in the presence of normal values for C3 is suggestive of C1 esterase inhibitor deficiency.

For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Report Available Methodology/Instrumentation
Mayo Clinic Laboratories​ ​Monday through Friday ​1 to 2 days ​Automated Liposome Lysis Assay
Reference Lab
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
86161​ ​1
​86160 ​2 ​If needed
For most current information refer to the Marshfield Laboratory online reference manual.