Peanut components: When it comes to peanut allergy, precision and proteins matter
Tim, a 6-year-old with a presumed history of peanut allergy, visits his healthcare provider because he’s never been tested for allergen sensitization.
Tim’s healthcare provider conducts a full clinical history and physical examination and decides to test using whole peanut allergen with reflex to components.
Find out how specific IgE testing can show if Tim has a clinical peanut allergy.
Patient History
Family History
- None
Tim's Personal History
- Tim experienced itching and tingling of the mouth and lips after eating a granola bar at age five.
- Tim’s parents assumed that reaction was due to peanut allergy.
- His previous healthcare provider recommended strict peanut avoidance.
Tim’s ImmunoCAP™ Test Results
These results, together with this patient's case history and symptoms, help confirm the diagnosis.
| Test | Type | Tim's Results |
Peanut |
Whole Allergen |
1.6 |
Ara h 1 |
Allergen Component |
<0.1 |
Ara h 2 |
Allergen Component |
<0.1 |
Ara h 3 |
Allergen Component |
<0.1 |
Ara h 8 |
Allergen Component |
2.79 |
Ara h 9 |
Allergen Component |
<0.1 |
Differential Diagnosis
Tim’s sensitization to Ara h 8 is associated with localized reactions, like itching and tingling of the mouth and lips, but low risk of systemic reaction. Tim may actually be sensitized to birch pollen, which is cross-reactive and responds similar to Ara h 8. Tim shows no detectable sensitization to three nut storage proteins associated with severe reactions.1-3
REFINED DIAGNOSIS
- Possible birch pollen allergy.
HEALTHCARE PROVIDER MANAGEMENT PLAN
- Tim’s healthcare provider advises that an oral challenge with peanut might reduce the fear of severe reactions based on his history.
- Tim passes the peanut oral food challenge without any symptoms.
FOLLOW UP
- Tim with his mother are seen by his healthcare provider one year later. Tim has had no further issues and is doing well.
The people, places, and events depicted in these case studies and photographs do not represent actual patients, nor are they affiliated in any way with Thermo Fisher Scientific.
- Asarnoj A, Nilsson C, Lidholm J, et al. Peanut component Ara h 8 sensitization and tolerance to peanut. J Allergy Clin Immunol. 2012;130(2):468-472
- Peeters KA, Koppelman SJ, van Hoffen E, et al. Does skin prick test reactivity to purifed allergens correlate with clinical severity of peanut allergy? Clin Exp Allergy. 2007;37(1):108-115.
- Asarnoj A, Movérare R, Östblom E, et al. IgE to peanut allergen components: relation to peanut symptoms and pollen sensitization in 8-year-olds. Allergy. 2010;65(9):1189-1195.
