The stung schoolboy — long case on insect-sting hypersensitivity

The story

Eight-year-old Liam was stung on the neck by a wasp during lunch break. Within three minutes he was flushed and scratching, then wheezy and distressed, and then he went grey and slumped against the wall. A teacher called an ambulance; paramedics found him hypotensive and wheezy with lip and tongue swelling, gave intramuscular adrenaline (300 micrograms) with oxygen and a fluid bolus, and he recovered fully. He was observed overnight and discharged with a provisional diagnosis of systemic anaphylaxis to wasp venom. He has mild asthma, well controlled on a preventer and a reliever, and no prior sting reactions. Six weeks later he and his parents attend your allergy clinic for the workup and the prevention plan. [2]

The history to take

Establish the timeline of the reaction (sting to collapse in minutes, multisystem), the absence of prior reactions, and the culprits he is exposed to at home and school (wasps near the lunch area, a hive-keeping neighbour). Confirm his asthma control and medication (no beta-blockers), his atopic background, and any family history of sting allergy. Explore the parents' understanding and their specific worries. [1]

The workup findings

Venom-specific immunoglobulin E is strongly positive to yellowjacket (Vespula) and weakly positive to honeybee; baseline serum tryptase is normal at 6 micrograms per litre; skin-prick and intradermal testing confirm genuine yellowjacket sensitisation with Ves v 5 positive on component-resolved diagnostics. There is no clinical or laboratory evidence of mastocytosis. The conclusion is a systemic anaphylactic reaction to yellowjacket venom in a sensitised, atopic child with a normal baseline tryptase and no clonal mast-cell disease. [1] [5]

The management decision

The acute event is resolved. The task now is prevention. Because Liam had a systemic anaphylactic reaction, the indication for venom immunotherapy with the yellowjacket extract is clear. Explain that venom immunotherapy builds up to a maintenance dose over weeks and then continues as maintenance injections every four to six weeks for three to five years, giving around 90 to 98 per cent protection against a systemic reaction to a subsequent sting. The normal baseline tryptase means a standard build-up is appropriate and the course can be time-limited rather than lifelong. [3] [4]

The discharge package

Prescribe an adrenaline autoinjector (300 micrograms) — two devices given his rural school — and a written anaphylaxis action plan. Provide medical identification, and arrange school education so staff can recognise a reaction and use the device. Optimise his asthma control, because asthma magnifies the bronchospasm of venom anaphylaxis. Review avoidance advice: footwear outdoors, avoiding nests and picnic areas, and not flailing at flying insects. Book the venom immunotherapy schedule and a clear follow-up plan. [2] [11]

Answering the family

Will he grow out of it? Children with venom allergy are somewhat more likely than adults to lose their reactivity over time, but a child who has had a systemic anaphylactic reaction retains a real risk of another severe reaction on re-sting; venom immunotherapy is the treatment that actively reduces that risk, which is why it is recommended rather than watchful waiting. [11]

Does the school need an autoinjector? Yes — he should carry one and the school should hold a second, with staff trained to use it and a copy of the action plan, exactly as for any child with anaphylaxis. [2]

Is venom immunotherapy worth three to five years of injections? For a systemic reaction, yes. It is the closest thing allergy has to a cure: it converts a dangerous, unpredictable risk into a near-negligible one, it removes the anxiety of every subsequent summer, and the protection persists after the course finishes. [4] [3]