Urticaria-Inducing Activity
Also known as: UIA
Use
This test helps determine the presence of autoantibodies that stimulate basophils in patients with suspected chronic urticaria. Chronic urticaria (CU) is a complex dermatological condition characterized by persistent hives lasting more than six weeks. In approximately 45% of cases, CU is associated with autoantibodies against basophil or mast cell-associated IgE or the high-affinity IgE-Fc receptor. Detection of histamine-releasing factors provides insight into the autoimmune nature of the condition, potentially guiding treatment approaches.
Special Instructions
Patients should discontinue calcineurin inhibitors 72 hours and prednisone two weeks prior to the specimen collection to ensure accuracy of the results. This test evaluates the presence of autoantibodies by assessing basophil/mast cell activation using a combination of histamine-release assays and serologic markers.
Limitations
The Urticaria-Inducing Activity test has not been cleared or approved by the US Food and Drug Administration and was developed as a Laboratory Developed Test (LDT) at ARUP Laboratories. Hence, while it adheres to CLIA guidelines and is intended for clinical use, its limitations include potential variability in histamine release assays and inherent challenges in standardizing basophil/mast cell activation measurements. It may not identify all cases of autoimmune urticaria due to the complex and varied nature of antibody interactions involved.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 63369-3
Result Turnaround Time
11-14 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Separate serum from cells ASAP or within 2 hours of collection. Freeze immediately.
Patient Preparation
Patients taking calcineurin inhibitors should stop their medication for 72 hours prior to draw. Patients on prednisone should be off medication for 2 weeks prior to draw.
Storage Instructions
CRITICAL FROZEN. Must be submitted in a separate vial if multiple tests are ordered.
Causes for Rejection
Specimens other than serum. Contaminated, grossly hemolyzed, or lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | Unacceptable |
| Frozen | 1 year |