Thermal Amplitude

Indications Determination of optimal temperature of reactivity of cold antibodies.  *Special collection procedures are required.
Method Standard test tube methodology, Hemagglutination
Test Information

The thermal amplitude test is performed to determine the reactivity of a cold autoantibody at varying temperatures: 4° C, 22° C, 30° C, and 37° C. Cold autoantibodies that are reactive at temperatures greater than 30° C have the potential to be clinically significant regardless of the antibody titer. When the IgM antibody reactions at greater than 30° C, it may be causing hemolysis (cold agglutinin syndrome, CAS).  Cold antibodies that are reactive at temperatures less than 30° C are not considered to be clinically significant. 

Please see sample information below for specific collection instructions 

Sample Requirements EDTA tube. Serum separator gel tube is not acceptable.
Requested Volume

1 full 7 ml EDTA sample
*Please see sample information below

Minimum Volume or Pediatric volume Minimum volume: 1 full 7 ml EDTA sample
Pediatric: 1 full 3 ml EDTA sample; neonate: 2 full 0.5 ml EDTA microtainers
Sample Information

Please call Immunohemtology Laboratory prior to drawing sample.

Sample drawn and maintained at 37°C. Once sample is separated, immediately transfer the plasma to a plastic tube labeled with patient's name and send to the lab.

Shipping Information Ship plasma at ambient temperature

Send samples to:
Bloodworks Northwest
Immunohematology Reference Laboratory
921 Terry Avenue
Seattle, WA 98104
Requisition Form RFT-Request for Testing Transfusion Services
Transaction Code 3140-00
CPT Codes 86940 and 86941
Test Schedule Monday through Sunday
Turn around Time (analytic time) 24 hours if weekday, 72 hours if weekend. This test is not performed on a STAT basis.
Report/ Results Fax number required to receive report