Long-term prospective observational study of patients with peanut and nut allergy after participation in a management plan.

摘要

BACKGROUND: Peanut and nut allergy is common and the most frequent cause of severe or fatal reactions to foods. Current advice is poor--doctors give an epinephrine injector to patients, without training or advice on nut avoidance--so that further reactions are common and deaths occur. We devised and assessed a management programme providing advice on nut avoidance and emergency medication. METHODS: Unselected referrals with confirmed peanut or tree-nut allergy were recruited. Severity of nut allergy was graded 1-5 and emergency medication allocated accordingly: oral antihistamine with or without inhaled or injected epinephrine. Patients, parents, and school staff received verbal and written advice on nut avoidance as well as training in recognition and self-treatment of reactions, with a written treatment plan. At follow-up (more than 13610 patient months) retraining was given and details of further reactions obtained. FINDINGS: 88 (15%) of 567 patients had a follow-up reaction of reduced severity. 62 of 88 were mild (grades 1-3, mainly cutaneous) and 49 patients used oral antihistamine, six inhaled adrenaline, and ten took no treatment. 12 of 12 patients with a moderate follow-up reaction improved after inhaled epinephrine. Only three (0.5%) of 567 patients, aged 27-40 years, had a severe follow-up reaction (involving dyspnoea) compared with 12% initially. Only one of 567 changed from a mild index reaction to a severe follow-up reaction. Patients with a moderate/severe (grade 4-5) reaction were older (median 18 years vs 9 years; p=0.03) and nine of 26 received injected epinephrine which was always effective. 85% of patients had no further reactions. Severity was related to the amount of nut eaten. INTERPRETATION: Self-treatment was effective (inhaled epinephrine for early laryngeal oedema and an epinephrine injector for severe reactions) but provision of this treatment, including who should carry epinephrine, required assessment of allergy severity. Our management plan was effective, and our results indicate that patients should be referred to specialist allergy centres for advice on nut avoidance.