Ex Vivo Challenge, Cell Culture and Histamine Analysis
Chronic Urticaria
CU Index
FCUIX
Serum
Patient Preparation: Patients taking calcineurin inhibitors should stop medication 72 hours prior to draw. Patients taking prednisone should be off their medication for 2 weeks prior to draw.
Specimen Type: Serum
Collection Container/Tube: Red or SST
Submission Container/Tube: Plastic vial
Specimen Volume: 2 mL
Collection Instructions:
1. Draw 5 mL blood in a serum separator tube (SST) (plain, red-top tube is acceptable).
2. Separate from cells within 2 hours of draw. Send 2 mL of serum ambient in a plastic vial.
0.5 mL
Hemolysis: | NA |
Thawing: | Warm OK; Cold OK |
Lipemia: | NA |
Icterus: | NA |
Other: | NA |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Ambient (preferred) | 14 days | |
Frozen | 14 days | ||
Refrigerated | 14 days |
Patients with a chronic form of urticaria who are positive (>10) with the CU index have an autoimmune basis for their disease. A positive result does not indicate which autoantibody (anti-IgE, anti-FceRI or anti-FCERII) is present.
< 10.0
The CU Index test is the second generation Functional Anti-FceR test. Patient with a CU Index greater than or equal to 10 have basophil reactive factors in their serum which supports an autoimmune basis for disease.
Ex-Vivo Challenge and cell culture: Donor blood cells are incubated with patient serum, a negative control and a positive control. Following the ex-vivo challenge, the cells are centrifuged and the supernatant is recovered for assay of histamine released. Histamine Analysis: Using a quantitative enzyme immunoassay, the histamine released into the supernatant is measured and compared to the total histamine in the basophils.
Monday and Thursday
This test was developed and its performance characteristics determined by Viracor Eurofins. It has not been cleared or approved by the U.S. Food and Drug Administration.
86343
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
FCUIX | CU Index | 63369-3 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
FCUIX | CU Index | 63369-3 |