Epidemiology
Sensitisation to wasp venom can occur after a single sting.
Most common in the late summer and early autumn.
Clinical features
Oedema, erythema and pain at the site of the sting which is a non-allergic reaction to the venom. This usually develops over hours and settles within a few days.
May cause blistering and secondary infection.
Mild reactions result in urticaria, pruritis and/or angio-oedema.
More severe reactions may cause anaphylaxis and can develop within 10 minutes.
Investigations
Wasp specific IgE (RAST) or skin-prick testing.
Management
Oral antihistamines for local reactions, with steroids reserved for more severe localised reactions
Adrenaline IM if any life-threatening features and systemic steroids.
Advice on avoidance.
Immunotherapy is effective and should be considered in patients with a history of severe generalised reactions.
Advice on avoiding wasp stings includes avoiding walking barefooted on grass, avoiding orchards, and not drinking directly from a can.
Contributed by Dr Sangeeta Dhami, GP Locum, Edinburgh, and Professor Aziz Sheikh, division of community health sciences, University of Edinburgh
