The majority of infants and children who presented with food-induced anaphylaxis (FIA) did not have eczema or food allergies, indicating that those who lack a personal history of atopy are nonetheless still at risk for sensitization at an early age, according to the results of a recent retrospective review published in the Annals of Allergy, Asthma & Immunology.1
Anaphylaxis was defined with the use of 3 criteria outlined in the Second Symposium on the Definition and Management of Anaphylaxis.2 Hypotension was defined as a systolic blood pressure <70 mm Hg in infants and <70 mm Hg+2 times age in children aged 1 to 10 years. Participants were included if they met 1 of the following conditions: an anaphylaxis smart phrase (a templated note used to collect necessary information for patients with anaphylaxis) was used in their medical record by an emergency department (ED) physician, or their medical records included ICD-9/10 codes for anaphylaxis.
Patient charts were reviewed using a standardized collection form to verify the clinical presentation of anaphylaxis, including vital signs, prior medical history, clinician’s examination findings, and disposition from the ED. Infants were assigned a symptom if healthcare providers chose that symptom in the smart phrase for anaphylaxis or described that symptom in their notes. If a caretaker noted a respiratory or skin finding that was described before ED arrival but was no longer present during the ED examination, these symptoms were assigned to a general category, such as “rash” or breathing difficulty.”
During the 2-year study period, 414 cases of anaphylaxis were diagnosed and were treated in the ED. Of these cases, 86% (357 of 414) were considered to be FIA and were included in the final analysis. Of the FIA cases reported, 47 occurred in infants, 43 in toddlers, 96 in young children, and 171 in school-aged children. No significant differences were reported among the 4 age groups with respect to sex, race, or ethnicity. School-aged children were significantly more likely to have public insurance compared with infants (27% vs 13%, respectively; P =.02).
Infants and toddlers presented with skin involvement more often than school-aged children (94% and 91% vs 62%, respectively; P <.001). Hives, which were the most common skin manifestation, were observed in significantly more infants than school-aged children (70% vs 54%, respectively; P =.001). Moreover, infants presented with gastrointestinal (GI) involvement significantly more often than other age groups (GI symptoms: 89% of infants vs 63% of toddlers [P =.003], 60% of young children [P =.006], and 58% of school-aged children [P <.001]). Vomiting was reported in 83% of infants with FIA.
Respiratory symptoms were more common in the older cohorts (17% of infants vs 54% of young children [P <.001] vs 49% of school-aged children [P <.001]). Wheezing was reported in 2% of infants vs 31% of young children (P <.001) and 22% of school-aged children (P =.001).
Eggs and cow’s milk were the most common foods that caused anaphylaxis in infants. Conversely, infants had significantly lower rates of anaphylaxis caused by peanuts and tree nuts than older patients.
The investigators concluded that considering the fact that most infants in the study experienced less severe reactions and had no atopic history compared with older children, all children might benefit from the early introduction of allergenic foods into their diet. This is the largest report to date to describe the symptomatology of FIA in infants <12 months of age compared with older patient populations.
1. Samady W, Trainor J, Smith B, Gupta R. Food-induced anaphylaxis in infants and children [published online May 31, 2018]. Ann Allergy Asthma Immunol. doi:10.1016/j.anai.2018.05.025
2. Sampson HA, Muñoz-Furlong A, Campbell RL, et al. Second symposium on the definition and management of anaphylaxis: summary report–Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium. J Allergy Clin Immunol. 2006;117(2):391-397.