Good prognosis, clinical features, and circumstances of peanut and tree nut reactions in children treated by a specialist allergy center
Received 26 February 2008; received in revised form 12 May 2008; accepted 12 May 2008. published online 01 July 2008.
Background
The diagnosis of nut allergy causes anxiety. Few studies exist that estimate risk of reactions and inform management.
Objective
To describe frequency and circumstances of reactions after the institution of a management plan.
Methods
Prospective study of children with peanut/nut allergy with an allergist's management plan. Severity and circumstances of worst reaction before diagnosis (index) and follow-up reactions were evaluated.
Results
A total of 785 children were followed for 3640 patient-years from diagnosis. Index reactions were mild in 66% (516), moderate in 29% (224), and severe in 5% (45). Fourteen percent (114/785) had follow-up reactions (3% annual incidence rate). Ninety percent had the same/reduced severity grade, and 1 of 785 (0.1%) had a severe reaction. Preschool children (n = 263) had a low incidence of reactions, and none were severe. There was a 3-fold reduction in injected epinephrine use from that used in the index reaction, required in 1 severe reaction, never twice; 14% (16/114) required no medication, 78% only oral antihistamines. Forty-eight percent reacted to the index nut type, 19% to a different nut (55% sensitized at diagnosis, 14% not sensitized, 31% not tested). Accidental versus index reactions were 4-fold more likely to be a result of contact exposure rather than ingestion. Contact reactions were always mild. Most (53%) reactions occurred at home, 5% in school, 21% at other sites (21% not recorded). The nut was given by a parent/self in 69 (61%) reactions or teacher in 5 (4%).
Conclusion
With a comprehensive management plan, accidental reactions were uncommon and usually mild, most requiring little treatment; 99.8% self-treated appropriately and 100% effectively.
Cambridge University Hospitals National Health Service Foundation Trust, Cambridge, United Kingdom
Reprint requests: Andrew T. Clark, MD, Cambridge University Department of Medicine, Box 157 Addenbrooke's Hospital, Cambridge CB2 2QQ, United Kingdom.
Disclosure of potential conflict of interest: A. T. Clark and P. W. Ewan both have received research support from the Food Standards Agency, United Kingdom government.
ABSTRACT