Table 1 Clinical criteria for diagnosing anaphylaxis
From: CSACI position statement: transition recommendations on existing epinephrine autoinjectors
WAO 2020 Criteria [3]: anaphylaxis is likely when any one of the following 2 criteria are fulfilled: | NIAID/FAAN Criteria [4]: fulfilling any 1 of the following 3 criteria indicates anaphylaxis is highly likely |
|---|---|
Criterion 1: | Criterion 1: |
Acute onset of an illness (minutes to several hours) with simultaneous involvement of the skin, mucosal tissue, or both (ex: generalized hives, pruritus or flushing, swollen lips-tongue-uvula) and at least one of the following: | Sudden onset of an illness (minutes to several hours), with involvement of the skin, mucosal tissue, or both (ex: generalized hives, itching or flushing, swollen lips-tongue-uvula) and at least one of the following: |
(i) Respiratory compromise (ex: dyspnea, wheeze-bronchospasm, stridor, reduced peak expiratory flow, hypoxemia) | (i) Sudden respiratory symptoms and signs (ex: shortness of breath, wheeze, cough, stridor, hypoxemia) |
(ii) Reduced BP or associated symptoms of end-organ dysfunction (ex: hypotonia, syncope, incontinence) | (ii) Sudden reduced BP or symptoms of end-organ dysfunction (ex: hypotonia, incontinence) |
(iii) Severe gastrointestinal symptoms (ex: severe crampy abdominal pain, repetitive vomiting), especially after exposure to non-food allergens | Criterion 2: |
Criterion 2: | Two or more of the following that occur suddenly after exposure to a likely allergen or other trigger for that patient (minutes to hours) |
Acute onset of hypotension or bronchospasm or laryngeal involvement after exposure to a known or highly probably allergen for that patient (minutes to several hours), even in the absence of typical skin involvement | (i) Sudden skin or mucosal symptoms and signs (ex: generalized hives, itch-flush, swollen lips-tongue-uvula) |
(ii) Sudden respiratory symptoms and signs (ex: shortness of breath, wheeze, cough, stridor, hypoxemia) | |
(iii) Sudden reduced BP or symptoms of end-organ dysfunction (ex: hypotonia, incontinence) | |
Sudden gastrointestinal symptoms (ex: cramping abdominal pain, vomiting) | |
Criterion 3: | |
Reduced blood pressure (BP) after exposure to a known allergen for that patient (minutes to hours) | |
(i) Infants and children: low systolic BP (age specific) or greater than 30% decrease in systolic BP | |
(ii) Adults: systolic BP of less than 90 mm Hg or greater than 30% decrease from that person’s baseline |