Hereditary Angioedema (HAE)

Test ID: 

705084

CPT code:

86160 (x2)

Synonyms:

Angioedema Profile
C1 Esterase Inhibitor Deficiency Profile

Clinical Use:

Aid clinicians in obtaining an appropriate diagnosis of hereditary angioedema (HAE). The profile begins with complement C4 and complement C1 esterase inhibitor with reflexing, if required, to complement C1 esterase inhibitor, functional to distinguish HAE type I from type II. If the results are not consistent with HAE consider other types of angioedema and/or retesting during an acute attack.

Test Information:

Rheumatoid factors (>200 IU/mL) significantly increase the apparent C4 concentration. This profile is not intended for the diagnoses of estrogen-dependent, estrogen-associated, drug-induced, or idiopathic angioedema. Also note that patients taking anabolic steroids may have falsely elevated C4 values thus limiting the effectiveness of the profile’s logic. Consider retesting the patient after discontinuation of anabolic steroids.

Specimen Type:

Serum, frozen and room temperature

Requested Volume: 

Three aliquots: one tube 0.5 mL frozen, two tubes 1 mL each at room temperature

Minimum Volume: 

Three aliquots: one tube 0.1 mL frozen, two tubes 0.5 mL each at room temperature

Container Type: 

Gel-barrier tube (preferred) or red-top tube. Note: Since specimen must be drawn on ice, plain red-top tubes will not clot as well as the use of clot-activated gel tubes.

Collection:

Collect sample on ice. Separate serum from cells in a refrigerated centrifuge. If a refrigerated centrifuge is not available, chill centrifuge tube carriers before centrifuging. Transfer aliquots of serum to each of three plastic transport tubes. Freeze the required 0.5 mL frozen aliquot immediately at -20°C.

Storage Instructions:

Frozen sample should not be stored at room temperature (15°C to 30°C) for longer than six hours.

Stability Requirements:

Required room temperature samples are stable for three days, frozen samples for 14 days.

Rejection Criteria

Plasma specimen; specimen not drawn on ice; stored specimen not frozen; gross bacterial contamination; excess lipemia; hemolysis; separate specimens not received (room temperature and frozen)