Table 1.

Clinical criteria for diagnosing anaphylaxis

Anaphylaxis is highly likely when any one of the following three criteria are fulfilled:

1. Acute onset of an illness (over minutes to several hours) with involvement of the skin, mucosa, or both (e.g., generalized hives, pruritus or flushing, swollen lips-tongue-uvula)

And at least one of the following

(a) Respiratory compromise (e.g., dyspnea, wheeze-bronchospasm, stridor, reduced PEF, hypoxemia)

(b) Reduced BP or associated symptoms of end-organ dysfunction [e.g., hypotonia (collapse), syncope, incontinence]

2. Two or more of the following that occur rapidly after exposure to a likely allergen for that patient (within minutes to several hours):

(a) Involvement of the skin-mucosal tissue (generalized hives, itch-flush, swollen lips-tongue-uvula)

(b) Respiratory compromise (e.g., dyspnea, wheeze-bronchospasm, stridor, reduced PEF, hypoxemia)

(c) Reduced BP or associated symptoms (e.g., hypotonia [collapse], syncope, incontinence)

(d) Persistent gastrointestinal symptoms (e.g., cramping abdominal pain, vomiting)

3. Reduced BP after exposure to a known allergen for that patient (within minutes to several hours):

(a) Infants and children: low systolic BP (age specific) or greater than 30 % decrease in systolic BPa

(b) Adults: systolic BP of less than 90 mmHg or greater than 30 % decrease from that person’s baseline

Modified from Sampson et al. [4]

PEF, peak expiratory flow; BP, blood pressure

^*Low systolic blood pressure for children is defined as less than 70 mmHg from 1 month to 1 year, less than [70 mmHg + (2× age)] from 1 to 10 years, and less than 90 mmHg from 11 to 17 years