Presentation on theme: "ANAPHYLAXIS The first documented case of anaphylaxis was in 2641 B.C., when Pharaoh Menes of Egypt died from a Wasp sting. While the first fatal reaction."— Presentation transcript:
ANAPHYLAXIS The first documented case of anaphylaxis was in 2641 B.C., when Pharaoh Menes of Egypt died from a Wasp sting. While the first fatal reaction to peanuts was described by a Canadian researcher Dr Evans in 1988. Allergy to venom from wasp stings can cause anaphylaxis as can allergy to latex and drugs such as penicillin and aspirin. Bee sting allergy is less common in the UK.
ANAPHYLAXIS The most common cause of anaphylaxis in the community is from eating a food to which you are allergic such as nuts, peanuts, eggs, mammalian milk, soya, wheat, fish and shellfish. These 8 foods account for 90% of cases of food induced anaphylaxis. Peanuts and tree nuts (such as Brazil nuts, Hazelnuts, Almonds and Walnuts) are the foods most likely to provoke a reaction.
ANAPHYLAXIS Some people may develop anaphylaxis after eating certain foods such as celery, shrimps, wheat, apple, hazelnut, squid and chicken and then exercising shortly after ingesting the food – triggering Exercise Induced Anaphylaxis.
SYSTEMIC ANAPHYLAXIS * Most extreme over-reaction of immune system * Caused by allergens which reach bloodstream * Venomous insect stings * IV and IM drugs * PO drugs (rapid absorption and high bioavailability)
Anaphylaxis- IgE-mediated Antibiotics and other medications Penicillins, β-lactams, tetracyclines, sulfas, vaccines, immunotherapy Foreign proteins Latex, hymenoptera venoms, heterologous sera, protamine, Foods Shellfish, peanuts, and tree nuts Exercise induced
SYSTEMIC ANAPHYLAXIS * Mechanism is widespread activation of mast cells throughout body resulting in * Vascular permeability (circulatory collapse / anaphylactic shock) * Constriction of smooth muscles * Death by constriction of airways and swelling of epiglottis
ANAPHYLAXIS The most common symptoms were urticaria and angioedema, occurring in 88% of patients. The next most common manifestations were respiratory symptoms, such as upper airway edema, dyspnoe and wheezing. Cardiovascular symptoms of dizziness, syncope, and hypotension, were less common, but it is important to remember that cardiovascular collapse may occur abruptly, without the prior development of skin or respiratory manifestations. Other symptoms of rhinitis, headache, substernal pain, and pruritus without rash were less commonly observed.
Most Common Clinical Manifestations of Anaphylaxis Symptom… How often? Urticaria /Angioedema 88% Upper airway oedema 56% Dyspnoe / bronchospasm 50% Flushing 51% Cardiovascular collapse “Anaphylactic shock” 30% GI 30%
ANAPHYLAXIS TREATMENT Prevention- avoid the allergen People with asthma and/or allergy have the risk of anaphylaxis, especially those with un- controlled asthma and/or severe allergy risk. These people should consult to an allergy specialist. When the anaphylaxis trigger has been identified by allergy testing, you must avoid the allergen very carefully.allergy testingallergen
TREATMENT OF SYSTEMIC ANAPHYLAXIS * Epinephrine is drug of choice * Sympathicomimetic drug acting on * Alpha receptors of vascular endothelium * Beta receptors of bronchial smooth muscles * Administered by I.M. injection into antero - lateral thigh * Do not inject into buttock * Do not inject I.V. * Cerebral hemorrhage * Epinephrine Auto-Injector (EpiPen) * Adult (0.3 mg) and pediatric (0.15)
Use of Epi Pen…. No contraindications in anaphylaxis !!! Failure or delay associated with fatalities I. M. may produce more rapid, higher peak levels vs S. C. Must be available at all times
ADMINISTRATION OF intramuscular ADRENALINE Intramuscular injection of epinephrine into the tigh – more effective than injection into the arm or subcutaneous administration
When to Repeat Epinephrine? Practice Parameter Update - US – Repeat every 5 minutes as needed to control symptoms and blood pressure – Some guidelines suggest liberalizing the frequency if deemed necessary – no absolute contraindication for epinephrine UK Consensus Panel on emergency Guidelines and International consensus guidelines for emergency cardiovascular care – May judiciously be repeated as often as every 5 minutes
Who Should Get Epinephrine? Everyone with rapid progression of symptoms Laryngeal edema Bronchospasm Severe GI symptoms Hypotension Highest fatality rates when epinephrine is delayed Age is not a limiting factor
Anaphylaxis Treatment –First Line ESTABLISH AIRWAY and supplemental O2 I.V. fluids Pulmonary symptoms: Albuterol by nebulization or MDI Deterioration of pulmonary symptoms : Racemic epinephrine by nebulization; Consider intubation or tracheostomy
After The Epi –Second Line Therapy For Everyone Antihistamines: H1 + H2 blockers Diphenhydramine 25-50 mg IV/IM/PO 1 mg/kg PO/ IM/ IV (kids) Ranitidine 50 mg IV…….. 4 mg/kg PO up to 300 mg 1.5 mg/kg IM/IV up to 50 mg (kids)
What About Non-Sedating H-1 blockers? Cetirazine (Zyrtec) 10 mg po q day Loratidine (Claritin) 10 mg po q day Desloratadine (Clarinex) 5 mg po q day Fexofenadine (Allegra)180 mg po q day Only available in oral form, long record of efficacy with urticaria
Other Second Line Considerations Inhaled beta-agonists - if wheezing Corticosteroids – 1-2 mg/kg prednisone PO – 1-2 mg/kg methylpredisolone IV (max 250 mg) Not helpful acutely ? Prevent recurrent anaphylaxis Glucagon ( if beta blocked) 1-5 mg slow IV, 1-5 ug/min
Treatment of Anaphylaxis… Observe for a minimum 8-12 hours Rebound or persitant symptoms Repeat epinephrine, repeat antihistamine ± H 2 blocker
This is a simple instruction of injecting EpiPen: Pull the seal cover. Put the black tip on your upper thigh (no need to undress the patient, unless the fabrics is too thick). Strongly press the EpiPen into your thigh until you feel the injection done. Hold the EpiPen for 10 seconds. Release the EpiPen while slowly massage the injected area. Call for medical help/ambulance. If the symptoms have not reduced after 30 minutes while you are waiting for medical help, give the second injection.
Anaphylaxis Fatalities Estimated 500–1000 deaths annually 1% risk Risk factors: Failure to administer epinephrine immediately Peanut, Soy & tree nut allergy (foods in general) Beta blocker, ACEI therapy Asthma Cardiac disease Rapid IV allergen Atopic dermatitis (eczema) Miller RL. Epidemiology of anaphylaxis. Presented at: Anaphylaxis: Safely Managing Your Patients at Risk for Severe Allergic Reactions. Postgraduate Institute for Medicine; October 8, 1999; Washington, DC.Bocher BS. Anaphylaxis. N Engl J Med 1991:324:1785–1790
Food-induced Anaphylaxis: Incidence 35%–55% of anaphylaxis is caused by food allergy 6%–8% of children have food allergy 1%–2% of adults have food allergy Incidence is increasing Accidental food exposures are common and unpredictable Kemp SF, et al. Anaphylaxis. A review of 266 cases. Arch Intern Med 1995; 155:1749–54. Pumphrey RSH, et al. The clinical spectrum of anaphylaxis in northwest England. Clin Exp Allergy 1996; 26:1364–1370. Bock SA. Prospective appraisal of complaints of adverse reactions to foods in children during the first 3 years of life. Pediatrics 1987;79:683–688.
Food-induced Anaphylaxis: Common Symptoms Oropharynx: Oral pruritus, swelling of lips and tongue, throat tightening GI: Crampy abdominal pain, nausea, vomiting, diarrhea Cutaneous: Urticaria, angioedema Respiratory: Shortness of breath, stridor, cough, wheezing
Food-induced Anaphylaxis: Fatal Reactions Fatal reactions are on the rise ~150 deaths per year ( in US ) Usually caused by a known allergy Patients at risk: Peanut and tree nut allergy Asthma Prior anaphylaxis Failure to treat promptly epinephrine Many cases exhibit biphasic reaction Anaphylaxis Committee, AAAAI. Anaphylaxis. Teaching Slides. 2000.
Venom-induced Anaphylaxis: Incidence 0.5%–5% (13 million) Americans are sensitive to one or more insect venoms Incidence is underestimated Incidence increasing due Incidence rising due to more outdoor activities At least 40–100 deaths per year
Venom-induced Anaphylaxis: Common Culprits Hymenoptera Bees Wasps Hornets
Venom-induced Reactions: Common Symptoms Normal: Local pain, erythema, mild swelling Large local: Extended swelling, erythema Anaphylaxis: Usual onset within 15–20 minutes Cutaneous: urticaria, flushing, angioedema Respiratory: dyspnoe, stridor Cardiovascular: hypotension, dizziness, loss of consciousness 30%–60% of patients will experience a systemic reaction with subsequent stings
Venom-induced Anaphylaxis: Prevention Risk Management Keep EpiPen or EpiPen Jr on hand at all times Educate and train on EpiPen use Develop emergency action plan Wear a MedicAlert bracelet Consult an allergist to determine need for venom immunotherapy
Venom-induced Anaphylaxis: Immunotherapy Medical criteria Venom immunotherapy is medically indicated in any adult with a history of a systemic reaction to an insect sting, and in children who have had life- threatening sting reactions. Positive venom skin test & sIgE 97% effective Can be discontinued in most after 3–5 years;
Exercise-Induced Anaphylaxis First reported in 1979 Mechanism of action is unclear Predisposing factors: ASA, Food, including: shell fish, cheese, dense fruits, snails. Triggered by almost any physical exertion Most common in very athletic children
Exercise-Induced Anaphylaxis Four Phases Prodromal phase is characterized by fatigue, warmth, pruritus, and cutaneous erythema The early phase: urticarial eruption that progresses from giant hives may include angioedema of the face, palms, and soles. Fully established phase: hypotension, syncope, loss of consciousness, choking, stridor, nausea, and vomiting ( 30 minutes to 4 hours.) Late or postexertional phase, Prolonged urticaria and headache persisting for 24-74 hours.
NON-IgE ANAPHYLAXIS Drugs Opiates NSAIDs ACE inhibitors Foods Strawberries Fish e.g. Tuna (Scrombotoxin)
Diagnosing Anaphylaxis Based on clinical presentation, exposure Cutaneous, respiratory symptoms most common Some cases may be difficult to diagnose Vasovagal syncope Systemic mastocytosis
Diagnosing Anaphylaxis Careful history to identify possible causes Can be confirmed by serum tryptase Specific for mast cell degranulation Remains elevated for up to 6-12 hours Serum histamine - rises w/in 5 minutes, returns to baseline after 30-60 minutes Other labs to rule out other diagnoses Refer to allergist for specific testing