Test ID C1INF C1 Esterase Inhibitor, Functional, Serum
Specimen Required
Patient Preparation: Fasting, preferred but not required
Supplies: Sarstedt 5 mL Aliquot Tube (T914)
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Immediately after specimen collection, place the tube on wet ice.
2. Centrifuge at 4° C and aliquot serum into a 5-mL plastic vial.
3. Freeze specimen within 30 minutes.
Useful For
Diagnosing hereditary angioedema
Monitoring response to C1 esterase inhibitor replacement therapy
Method Name
Enzyme Immunoassay (EIA)
Reporting Name
C1 Esterase Inhib, Functional, SSpecimen Type
Serum RedSpecimen Minimum Volume
0.4 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum Red | Frozen | 28 days |
Reference Values
>67% normal (normal)
41-67% normal (equivocal)
<41% normal (abnormal)
Day(s) Performed
Varies
Report Available
3 to 5 daysPerforming Laboratory

Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83520
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
C1INF | C1 Esterase Inhib, Functional, S | 48494-9 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
C1INF | C1 Esterase Inhib, Functional, S | 48494-9 |