Sign in →

Test Code 0232736 C5 Complement, Antigen, Serum

Additional Codes

Mayo Test ID
C5AG

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Useful For

Diagnosis of C5 deficiency

 

Investigation of a patient with an absent total complement (CH50) level

Method Name

Nephelometry

Reporting Name

C5 Complement, Antigen, S

Specimen Type

Serum


Advisory Information


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 but not required

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions: Centrifuge and separate serum from clot.


Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time
Serum Frozen (preferred) 60 days
  Refrigerated  28 days
  Ambient  7 days

Reject Due To

Hemolysis

Mild OK; Gross OK

Lipemia

Mild OK; Gross reject

Icterus

Mild OK; Gross OK

Other

NA

Reference Values

10.6-26.3 mg/dL

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 C5 levels in the presence of normal C3 and C4 values are consistent with a C5 deficiency. Absent C5 levels in the presence of low C3 and C4 values suggests complement consumption.

 

A small number of cases have been described in which the complement protein is present but is nonfunctional. These rare cases require a functional assay to detect the deficiency C5FX / C5 Complement, Functional, Serum).

Day(s) and Time(s) Performed

Monday, Wednesday, Friday

Analytic Time

Same day/1 day

Specimen Retention Time

14 days

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

86160

LOINC Code Information

Test ID Test Order Name Order LOINC Value
C5AG C5 Complement, Antigen, S 4505-4

 

Result ID Test Result Name Result LOINC Value
C5AG C5 Complement, Antigen, S 4505-4