Anaphylaxis — Child with Suspected Anaphylaxis — Clinical Pathway: Outpatient

Anaphylaxis Clinical Pathway — Outpatient Specialty Care and Primary Care

Child with Suspected Anaphylaxis

This pathway is intended for infants and children > 2 months old or weighing more than 5 kg. Providers should use individual clinical decision-making when caring for infants with suspected anaphylaxis < 2 months old or weigh < 5 kg.

Clinical Criteria for Diagnosing Anaphylaxis

Anaphylaxis is highly likely when one of the following three criteria is fulfilled within minutes to 2-3 hours following possible allergen exposure
Criteria 1

Acute onset of an illness with involvement of the skin, mucosal tissue, or both
(e.g., generalized hives, pruritis or flushing, swollen lip-tongue-uvula)

And at least one of the following:
  • Respiratory compromise
  • Reduced BP or associated symptoms of end-organ dysfunction
  • Persistent GI symptoms, significant abdominal pain and/or significant vomiting
Criteria 2

Two or more of the following that occurs rapidly after exposure to a likely allergen for that child:

  • Involvement of the skin-mucosal tissue
  • Respiratory compromise
  • Reduced BP or associated symptoms
  • Persistent gastrointestinal symptoms
Criteria 3 Reduced BP after exposure to known allergen for that child

Anaphylaxis Caveats

  • A child who presents with hypotension alone after exposure to known allergen meets anaphylaxis criteria
  • While the majority of anaphylaxis cases involve skin symptoms, 10% of children do not have hives or other skin manifestations; these children often have the most severe symptoms
  • Isolated skin findings alone (generalized hives) should not automatically be defined as anaphylaxis
  • In a child with exposure to a known allergen that has previously caused anaphylaxis that presented with hives alone, threshold should be low for the diagnosis of anaphylaxis
  • The above signs/symptoms obviously can be due to non-allergic causes
  • The absence of exposure to a known allergen should never preclude the diagnosis of anaphylaxis
  • Children on beta blockers should get glucagon if the first dose of epinephrine is ineffective

Examples of Anaphylaxis

  • Child with history of peanut allergy presents with acute onset of generalized hives and wheezing after possible or known exposure to peanut
  • Child with history of milk allergy presents with acute onset of lip/tongue swelling and vomiting after possible or known exposure to milk
  • Child with history of shellfish allergy presents with acute onset of persistent cough, rhinorrhea, and crampy abdominal pain after possible or known exposure to shellfish
  • Child with no history of allergies presents with acute onset of hives, wheezing, and vomiting soon after eating peanuts
  • Child with history of tree nut allergy presents with acute onset hypotension after accidentally eating almonds