C2 Complement, Functional, Serum

Alphabetical Test listing

C2 Complement, Functional, Serum-1334

Test name:

Test number:

1334

Excellian order number:

86160.3

Abbreviation:

Alternate names:

C2 Functional
C2 Complement, Functional, S, NR
C2FXN

Useful for:

Investigation of a patient with a low (absent) hemolytic complement

Patient preparation information:

Fasting preferred but not required

Specimen type:

Serum

Collection container:

Red serum vial/tube, 5 mL

Volume:

1 mL

Minimum volume:

0.5 mL

Collection instructions:

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

Processing instructions:

Allow sample to clot on wet ice
Spin within two (2) hours of sample collection
Transfer serum to a Screw cap transfer vial/tube (Mayo T465), labelled as serum
Immediately freeze specimen

Transport container:

Screw cap transfer vial/tube (Mayo T914)

Transport and stability:

Frozen - 21 days

Specimen retention time:

14 days

Reason for rejection:

Gross lipemia

Performing lab:

Mayo Clinic Laboratories (C2FXN); R-NX

Days set up:

Mo - Fr

TAT:

2-4 days

Method:

Automated Liposome Lysis Assay

Reference ranges:

25-47 U/mL

Clinical information:

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.

Cautions:

As with all complement assays, proper sample handling is of utmost importance to ensure that the complement system is not activated before clinical testing.

CPT codes:

86161

Date created:

11/07/2023

Review date:

11/07/2023