دکتر افشین شیرکانی فوق تخصص آسم و آلرژی و بیماری های نقص ایمنی عضو آکادمی آسم و آلرژی و ایمونولوژی آمریکا استادیار دانشگاه
Anaphylaxis is an acute onset, potentially fatal, systemic allergic or non-allergic reaction Lifetime prevalence=0.05%-2%. Largest number of cases in children and/or adolescents Anaphylaxis( IgE-Mediated) Anaphylactoid reaction (Non-IgE-Mediated)
Intermittent admin Age Atopy Time since reaction Gender
Signs and Symptoms : Urticaria and/or angioedema Shortness of breath Syncope and/or dizziness Diarrhea Flushing Laryngeal edema Nausea and/or emesis Hyportension Rhinitis Periorbital edema Chest pain Pruritus Headache
Cutaneous (90%) Respiratory (70%) Gastrointestinal (30%-45%) Cardiovascular (10%-45%) Central nervous system (10%-15%) Patients who do not experience skin manifestations may experience profound shock immediately
Asthma Ingested allergen Prior personal history of biphasic reaction Receiving less epinephrine Receiving less corticosteroid
Clinical History : More than one target organ is involved (GI, RT,Skin, Cardiovascular);and, history often involves provocation by known food, drug, or insect allergen exposure
Check serum histamine minutes: levels begin to rise by five minutes but remain elevated only minutes Check serum tryptase minutes: peaks minutes after the onset of symptoms and can remain elevated as long as five hours Check urinary histamine later: metabolites may remain elevated as long as 24 hours tryptease may not be elevated in food-induced anaphylaxis
Investigate suspected allergens or triggers for specific IgE by skin prick test (SPT) or in vitro methods. SPT is often performed at least four to six weeks after the episode due to refractory period of mast cells that can create false negatives. Selection of foods for testing should be guided by the history
1.Short term: Epinephrine at dose of 0.01 mg/kg (often as mL of 1:1000) IM ABCs, supine positioning, and establishment of an airway. Skin inspection Supplemental oxygen, insertion of one or more large-bore IVs for fluids Even if on β-blockers, administer epinephrine first but consider glucagon. (Also, recall IV fluids are particularly important for patients unresponsive to epinephrine.)
2.Long term: Epinephrine auto-injector Emergency action plan and medical alert bracelet Relevant and specific preventive treatment