Anaphylaxis is a rapid onset, IgE-mediated systemic allergic reaction affecting two or more organ systems including the skin, respiratory tract, gastrointestinal tract, and circulatory system. Common allergens that can trigger anaphylaxis in children are foods like peanuts, tree nuts, eggs, and shellfish, as well as insect bites, medications like beta-lactams, and exercise. Initial management of anaphylaxis involves administering epinephrine intramuscularly, providing supportive care, establishing IV access, administering antihistamines and steroids, and monitoring for potential recurrence of symptoms over 72 hours.

1. ANAPHYLAXIS
Noora Al-Suwaidi
Pediatrics Resident

2. DEFINITION
• A rapid onset of Ig-E mediated systemic allergic reaction involving multiple
organ systems, including 2 or more of the following :
a. Cutaneous/mucosal ( flushing, urticaria, pruritus, angioedema) seen in 90%
of cases
b. Respiratory ( laryngeal edema, bronchospasm, dyspnea, wheezing, stridor,
hypoxemia) seen in 70% of cases
c. GI ( vomiting, nausea, diarrhea, crampy abdominal pain ) seen in 40%-50%
d. Circulatory ( tachycardia, hypotension, syncope) seen in 30-40% of cases
• Initial reaction maybe delayed for several hours AND symptoms may recur
after 72 hours after initial recover
NB: so patients need to be observed for at least 6-72 hours from the initial
symptoms

3. COMMON ALLERGENS
• Common causes of anaphylaxis in children include:
• Foods - Peanut, tree nuts, cow milk, eggs, soy, shellfish, fish, wheat
• Bites/stings - Bee, wasp, jack jumper ants
• Medications- Beta-lactams
• Other - exercise, idiopathic

4. RISK FACTORS FOR FATAL ANAPHYLAXIS
• Poorly controlled asthma
• Allergy to nuts, shellfish, drugs and insect stings
• Adolescence
• Delay to administration of adrenaline or emergency response services
• Pre-existing cardiac and respiratory conditions

5. INITIAL MANAGEMENT
• Remove/stop exposure to precipitating antigen
• Epinephrine ( while performing ABCs, immediately give a dose of
epinephrine IM 0.01 mg/kg which is equivalent to 0.01 ml/kg of 1:1000 )
repeat every 5 minutes as needed at the lateral surface of the thigh
• Establish airway and give oxygen and PPV as needed
• Obtain an IV access, Trendelenburg position with head 30 degrees
below feet, administer fluid boluses followed by pressers as needed

6. • H-1 receptor antagonist such as diphenhydramine, 1-2 mg/kg IM,IV or
oral
• Corticosteroids- help to prevent the late phase of the allergic response.
Administer methylprednisolone in a 2mg/kg IV bolus followed by
2mg/kg/day divided 6qh or prednisolone 2mg/kg OD
• Albuterol 2.5 mg for < 30 kg, 5 mg >30 kg for bronchospasm or wheeze
every 15 minutes as needed
• Racemic epinephrine 0.5 ml of 2.25% solution inhaled for signs of upper
respiratory obstruction
• Discharge on Epi-pen and with anaphylaxis action plan