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Lab Manual for Moffitt-Long and Mount Zion

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IgE, Specific

Item Value
Approval req'd? No
Available Stat? No
Test code IGES, BTRAST
Performed by Quest
Sendout? Yes
Method Pharmacia PCS system (successor to RAST testing)
Container type Gold top
Amount to Collect 1 mL blood per allergen
Sample type Serum
Preferred volume 0.5 mL serum per allergen
Min. Volume 0.3 mL serum for one test
Processing notes Refrigerate serum.

Mark the appropriate Quest # from the test listing on the reference lab request slip, and order the proper Charge Group of the test in the laboratory computer.

Charge group 1 IGE1
Charge group 2 IGE2
Charge group 3 IGE3
Charge group 4 IGE4
Charge group 5 IGE5
Charge group 6 IGE6
Charge group 7 IGE7
Charge group 8 IGE8
Charge group 9 IGE9


Brown and Toland patient s require prior authorization. For B&T patients order "BTRAST" for each allergen. Refer to Labcorp test directory for correct test number.

The free text result should include the name of the allergen, the level of specific IgE, the % binding, the "Class" and the interpretation.

List of Available Allergens
Units KU/L and %
Normal range
Undectectable Ab < 0.35 KU/L
Low level Ab 0.35-0.70 KU/L
Moderate level Ab 0.71-3.50 KU/L
High level Ab 3.51-17.5 KU/L
Very High level Ab > 17.5 KU/L


Asm. % Ref Interpretation
< 70 None detected
70-109 Very low positive
110-219 Low positive
220-599 Moderate positive
60-1999 High positive
2000-5999 Very high positive
> 5999 Extremely high positive


Note: LabCorp Reference range for B&T patrients

< 0.08 KU/L
Synonyms RAST; PCS
Stability Room temperature or refrigerated 2 weeks, frozen at -20C 1 month.
Turn around times Test performed Monday-Friday. Turnaround time: 3-4 days.
Additional information It is generally believed that reactivity of Class 2 or below is not an indication for immunotherapy.

A NEGATIVE RESULT CAN OCCUR IN A SENSITIZED INDIVIDUAL WHO HAS NOT BEEN EXPOSED TO A PARTICULAR ANTIGEN FOR A PROLONGED PERIOD OF TIME, AND MAY ALSO OCCUR IN AN INDIVIDUAL WHO HAS VERY RECENTLY SUFFERED A SEVERE ALLERGIC REACTION.

Due to the rise and fall of circulating antibodies to venoms and to penicillin G or V, specimens should be collected no sooner than 2-3 weeks and no later than 6 months after an insect sting or a penicillin exposure.

See the list of antigens available for testing below, organized both alphabetically overall and by allergen type, e.g., foods, grasses, etc. Common inhalant allergens in Northern California are marked with a *.

List of Available Allergens

Tests must be ordered individually rather than in (more expensive) panels.

Medicare/MediCal will not reimburse testing for specific IgE in a patient who has not previously demonstrated an elevation of total IgE.

Brown & Toland patients require prior authorization for these tests.
Last Updated 7/24/2012 9:26:43 AM
Entry Number 553

If you have additional questions regarding this test, please call: 415-353-1667

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