Ordering Recommendation

Follow-up test for complement activity screening when CH50 is normal and AH50 is low.

Mnemonic
COMP FAC B
Methodology

Quantitative Radial Immunodiffusion

Performed

Mon, Wed, Fri

Reported

4-7 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Serum separator tube.

Specimen Preparation

Allow specimen to clot for 30 minutes to one hour at refrigerated temperature. Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube and place on refrigerant pack or freeze immediately. (Min: 0.3 mL)

Storage/Transport Temperature

Frozen.

Unacceptable Conditions

Room temperature specimens. Specimens exposed to repeated freeze/thaw cycles.

Remarks
Stability

After separation from cells: Ambient: Unacceptable; Refrigerated: 48 hours; Frozen: 1 year

Reference Interval

20-51 mg/dL

Interpretive Data



Compliance Category

Laboratory Developed Test (LDT)

Note
Hotline History
N/A
CPT Codes

86160

Components
Component Test Code* Component Chart Name LOINC
0051721 Complement Factor B 2269-9
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Alternative Pathway - Complement
  • Complement alternative pathway
  • Properdin Factor B
Complement Factor B