Test Overview
Test Methodology
Radial Immunodiffusion
Test Usage
Decreased values are seen when the alternate pathway of complement is activated.
Reference Range *
127.6 - 278.5 mcg/mL
Test Details
Analytic Time
4 weeks
Soft Order Code
MMLR
Synonyms
- Factor B level by RID
- PFB
- Complement (C3) Proactivator
- Complement (C3) PA
- Complement (C3) Activator
Laboratory
Sendout
Reference Laboratory
Mayo Wild 85 (ZW85) (National Jewish Health FBL)
Section
Special Testing
Specimen Requirements
Collection Instructions
Collect specimen in a lavender top tube. Centrifuge, aliquot plasma into a plastic vial within 30 minutes of collection, and freeze.
Normal Volume
1 mL EDTA plasma
Minimum Volume
0.5 mL EDTA plasma
Additional Information
Activation via the alternate pathway is facilitated by particulate surfaces such as bacterial cell walls or complex polysaccharides. Alternate pathway activation is associated with nonimmune events. Decreased levels of PFB together with a decrease in serum C3 are indicative of significant and prolonged alternate pathway activation of complement. Test sent to Mayo Medical Laboratories; performed by National Jewish Health.
Billing
CPT Code
86160
Fee Code
21935
NY State Approved
No