C1 Esterase Inhibitor Protein

Overview

  • EPIC Code:
  • LAB2522
  • Soft Test Code:
  • C1EST
  • Send Out Test Code:
  • 298
Alternate Names
  • C1 Esterase
  • C1 Esterase Inhibitor, Total
  • C1 Inhibitor Protein
Clinical Significance

The C1 esterase inhibitor protein is a normal constituent of serum which functions as a serine proteinase inhibitor of the serpin family. The C1 esterase inhibitor inhibits the complement proteases C1r and C1s, as well as the proteases kallikrein, factor XIa, XIIa and plasmin of the blood clotting system. The concentration of C1 esterase inhibitor protein is reduced to 10-30% of normal in patients with angioedema secondary to C1 esterase inhibitor deficiency (85% of patients with Hereditary Angioedema (HAE)); In 15% of patients with HAE, the concentrations of the inhibitor protein is normal but function is markedly reduced.


Specimen Collection & Preparation

Specimen Requirements

1.0 mL Serum from a Red Top Tube in a Plastic Vial


Alternate Specimen

1.0 mL Serum in a SST Gold Top Tube


TransportAndStorage

7 days Ambient (Transport)
8 days Refrigerated
1 year Frozen


Collection Instructions

 


Minimum Volume

0.5 mL


Neonatal Volumne

Clinical Interpretation

Reference Range:

21 - 39 mg/dL


Test Comments:

Limitations;Fifteen percent of patient with the inherited form of the disease will test within range.


Methodology:
  • Nephelometry

Clinical Significance

The C1 esterase inhibitor protein is a normal constituent of serum which functions as a serine proteinase inhibitor of the serpin family. The C1 esterase inhibitor inhibits the complement proteases C1r and C1s, as well as the proteases kallikrein, factor XIa, XIIa and plasmin of the blood clotting system. The concentration of C1 esterase inhibitor protein is reduced to 10-30% of normal in patients with angioedema secondary to C1 esterase inhibitor deficiency (85% of patients with Hereditary Angioedema (HAE)); In 15% of patients with HAE, the concentrations of the inhibitor protein is normal but function is markedly reduced.


Production Schedule

Sites Performed
  • Quest - Chantilly
Days Performed
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Departments
  • Sendouts - Clinical
Turn Around Time

3 to 5 days


Coding & Compliance

CDM

01454224


CPT Coding

86160