Determine histamine release in suspected chronic urticaria if urticaria may be due to autoimmune antibodies to the basophil IgE receptor or to IgE.
Semi-Quantitative Ex Vivo Challenge/Cell Culture/Quantitative Enzyme-Linked Immunosorbent Assay
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.
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube and freeze immediately. (Min: 0.5 mL)
CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.
Specimens other than serum. Contaminated, grossly hemolyzed, or lipemic specimens.
After separation from cells: Ambient: Unacceptable; Refrigerated: Unacceptable; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Effective November 14, 2011
10 units or less
A value of greater than 10 units suggests the presence of basophil stimulating antibodies (or other serum factors).
Laboratory Developed Test (LDT)
1) Chronic urticaria (CU) is a common and complex dermatological condition that is suspected when patients experience persistent hives for over 6 weeks. No published evidence of an exogenous allergen as the cause of this disorder exists. About 45 percent of cases have autoantibodies directed against either basophil or mast cell-associated IgE or the high affinity IgE-Fc receptor (Fc epsilon R1 alpha) (Clin Exp Allergy 2009; 39: 777-87).
2) The presence of histamine-releasing factors (including but not limited to IgE and Fc epsilon R1 alpha-specific autoantibodies) in the patient serum can be indirectly determined by evaluating basophil/mast cell activation status using histamine-release assays, autologous serum-skin test, and flow cytometric measurement of the basophil and mast cell-specific marker CD203c. Serum from CU patients can activate donor basophils, which induces histamine release and CD203c upregulation (J Allergy Clin Immunol 2006; 117: 1430-4).
|Component Test Code*||Component Chart Name||LOINC|
- CD203c upregulation