Complement Component C1q

Complement C1Q, C1q Complement, Serum

Test Codes

EPIC: LAB1232038, Beaker: COMPLEMENTC1, Quest: 981

Department

Send Outs

Specimen Collection Criteria

Collect (preferred specimen): One Gold-top SST tube.
Also acceptable: One plain Red-top tube.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells within one hour of collection. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Preparation for Courier Transport

Transport: 1.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 0.1 mL)

Rejection Criteria

• Gross hemolysis.
• Grossly lipemic.
• Received room temperature.
• Specimens not collected and processed as indicated.

In-Lab Processing

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells within one hour of collection. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Transport: 1.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 0.1 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 4 days
Refrigerated (2-8°C or 36-46°F): 10 days
Frozen (-20°C/-4°F or below): 29 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Laboratory

Sent to Quest Diagnostics, Wood Dale, IL.

Performed

Tuesday, Thursday.
Results available in 4-9 days.

Reference Range

5.0-8.6 mg/dL

Test Methodology

Radial Immunodiffusion (RID)

Interpretation

By report.

Clinical Utility

Complement Component C1q - The complement system is critical to the inflammatory response.  C1q concentrations may be decreased in patients with acquired angioedema, immune complex induced vasculitis, and concurrent low concentrations of C1 inhibitor, carcinoma, or lymphoma.

CPT Codes

86160
LOINC:  4478-4

Contacts

Last Updated

12/17/2025