Anaphylaxis%20(pediatric) Management

Patient Observation

• Considered in post-anaphylactic patients due to risk of biphasic reaction or possible recurrence as the effect of Epinephrine wears off
• Biphasic reaction is the recurrence of symptoms after the initial episode of anaphylaxis has resolved without any further exposure to the trigger
  
  • Occurs in 1-23% of anaphylaxis cases
  • Onset of the 2nd phase of reaction ranges from 1-72 hour after the initial reaction
  • Risk factors include: More severe initial presentation of anaphylaxis, initial reaction requiring >1 dose of Epinephrine, delay in Epinephrine administration

• Children <16 years old should be admitted for observation; young people ≥16 years old should be observed for 6-12 hours from onset of symptoms
• The period of observation will vary from 4-24 hours depending on the clinical situation
  • Patients with respiratory symptoms would require 6-8 hours of observation
  • Patients with hypotension/shock require 12-24 hours of observation in ICU
  • Longer period of observation may be provided to patients with risk factors for developing severe anaphylaxis, those who required >1 dose of Epinephrine, or protracted anaphylactic episode

• Patients should be followed up for 7 days after the observational period for occurrence of biphasic reactions

Allergy and Anaphylaxis Prevention

• In the history, take note of allergy record of patient’s parents, siblings, relatives on maternal or paternal side
  • Predictive family score may be used to identify patients at-risk of developing allergy
  • A family history of asthma and allergy identifies children at high risk for developing allergic disease

Avoidance Management

• Should be individualized based on factors such as age, occupation, activity, hobbies, environment, patient’s level of anxiety and access to medical care
• Avoidance of co-triggers (eg food, NSAIDs, alcohol) and exercise during extreme weather can help prevent exercise-induced anaphylaxis and food-dependent exercise-induced anaphylaxis
• Delaying of food ingestion 2-4 hours prior to exercise may prevent food-dependent exercise-induced anaphylaxis
• Patient education is the most important strategy since avoidance measures may not always be successful
  • Educating patients or caregivers on self-management of anaphylaxis is important
  • Should include emphasis on hidden allergens, risk of future anaphylaxis, cross-reactivity between drugs and various allergens

• Know the possible risk factors contributing to severe anaphylaxis resulting from injections of immunotherapy with measures for prevention and management of severe systemic allergic reactions

Other Approaches

• Pharmacologic prophylaxis (eg antihistamines, glucocorticosteroids)
  • May help prevent idiopathic anaphylaxis, recurrent anaphylaxis to radiographic materials

• Venom immunotherapy (VIT)
  • Recommended as therapy for venom allergy in children
  • Found to be effective in up to 98% of patients with history of venom-induced anaphylaxis
  • Studies show that a 3- to 5-year course of SC immunotherapy with insect venom can prevent recurrences of insect venom anaphylaxis

• Drug desensitization
  • An alternative therapy for drug-induced anaphylaxis of patients unresponsive/intolerant to traditional therapies
  • Done by continuously administering the drug allergen at increasing doses over a short period of time, until the therapeutic dose is reached

Breastfeeding and Milk Formulas

• Exclusive breastfeeding of infants until 4-6 months is recommended, especially in children at high risk of allergic disease
  • Reported protection against allergic disease in the early years of life is relatively small, and some studies suggest an increased risk of disease in later life

• Evidence to support dietary changes for breastfeeding mothers to prevent food allergy in their child is also lacking
• If breastfeeding is not possible in high-risk infants, a hydrolyzed formula is recommended
• Extensively hydrolyzed casein and partially hydrolyzed whey formulas have been shown to have preventive effects
  • These effects have only been demonstrated in high-risk infants with atopic heredity

• Prospective studies have shown that soy formula and other milks (eg goat’s formula) are not recommended for the reduction of food allergy risk
• More studies are needed to support the use of probiotics/prebiotics for infant diet supplementation

Solid Food

• It is recommended that introduction of solid food, including those with potential allergens, should be done at the age of 4-6 months, without delay
  • There is insufficient evidence that dietary restriction should be done for high-risk patients, thus not recommended
• Introduction of peanuts into the diet of ≥6-month-old infants with mild-moderate atopic dermatitis is recommended
  • For infants aged 4-6 months with severe atopic dermatitis, egg allergy, or both, consider IgE measurement prior to introduction of peanut-containing foods

• Patients should be referred to age-specific allergy specialist at the earliest possible time after the reaction
• Referral to an allergist-immunologist is indicated in the following circumstances:
  • To take a full allergy-focused history
  • To perform tests to determine the cause of anaphylaxis and confirm the diagnosis
  • To develop an individualized management plan and be able to train the patient and caregivers to ensure implementation of management plan
  • To offer information on avoidance and control of confirmed trigger factors
  • If symptoms are recurrent or difficult to control
  • If patient is a candidate for immunotherapy or desensitization
  • If daily medications for prevention is required