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Test Code
CEIQ
Test Name
C1-Esterase Inhibitor Functional
CPT Codes
86161
Expected Turnaround Time
3 - 5 days
Clinical Utility

Esterase inhibitor is decreased in hereditary angioneurotic edema. Functional level will be decreased when concentration of inhibitor is decreased or inhibitor is nonfunctional.
Specimen and Container Info

Specimen Type: Serum

Alternate Specimen Type: Plasma

Collection Container: Red Top, Plain

Alternate Collection Container: Lavender Top (EDTA) 

Desired Specimen Volume: 0.5 mL
Collection Instructions
  1. Collect red top plain tube via venipuncture
Processing and Submission Instructions
  1. Separate serum from cells.
  2. Transfer 0.5 mL of serum to a clear aliquot tube.
  3. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Room Temperature

Serum: 6 hours

Plasma: 24 hours

Frozen

7 days
Causes for Rejection
  • Plasma other than EDTA
  • Thawed or nonfrozen sample
Methodology
Enzyme Immunoassay
Reference Intervals

See patient report.
Alternate Names
  • C1 Esterase Inhibitor
  • C1 Inactivator
  • C1 Inhibitor
  • Esterase Inhibitor
  • Hereditary Angioneurotic Edema Test
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Routine, 3 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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