Peanut (PN) and tree nuts (TNs) are well-recognized as major causes of anaphylaxis in Western countries but no information is available in Korea. The purpose of this study was to feature clinical characteristics of anaphylaxis caused by PN, TNs and seeds in Korean children and adolescents.
A retrospective medical record review was performed on patients (0~18 years old) diagnosed with anaphylaxis from PN, TNs (walnut, almond, hazelnut, pine nut, cashew nut, pistachio, pecan and macadamia) and seeds (sunflower, sesame and perilla) between 2009 and 2013 in fourteen university hospitals in Korea.
One hundred and twenty-six cases of anaphylaxis from PN, TNs and seeds were identified (64.3% in male patients) and the mean age was 4.9 years (0.8-18.9 years), with 81.7% of subjects under seven years old. The number of patients increased from 9 cases in 2009 to 57 cases in 2013. PN accounted for 32.5%, walnut (WN) accounted for 41.3%, pine nut accounted for 7.1%, and other TNs and seeds accounted for 19.1%. The most common system involved was cutaneous (96.0%), followed by respiratory (87.3%) and gastrointestinal (26.2%). The proportion of patients with cardiovascular symptoms was significantly higher in older patients than in younger children (p = 0.001). The time intervals between ingestion of triggering food and onset of symptoms were immediate in 19.0% and less than two hours in 42.9%. Among 104 cases (82.5%) in which serum levels of specific IgE (sIgE) to corresponding allergens were measured, the median values of sIgE to PN, WN and pine nut were 10.50 (0.39-100.00) kUA/L, 8.74 (0.04-100.00) kUA/L and 4.61 (0.60-4.61) kUA/L, respectively. Among 50 cases managed in the emergency department, patients were treated with intramuscular epinephrine in 52.0%, with systemic steroid in 66.0%, with antihistamine in 94.0%, with oxygen in 36.0%, and with bronchodilator in 48.0%. The overall percentage of patients prescribed an epinephrine auto-injector was 48.4%, with no significant differences between age groups.
Among anaphylaxis caused by PN, TNs and seeds in Korea, WN, PN and pine nut were the 3 most common triggers in order, and 9 other kinds of TNs and seeds were also identified as triggers. About 82% of cases were in children under the age of seven. The median levels of sIgE to PN and WN were 10.50 kUA/L and 8.74 kUA/L, respectively, and some of cases showed remarkably low sIgE levels, and < 0.35 kUA/L in three subjects.
* This study was done by Food Allergy and Atopic Dermatitis Study Group in the Korean Academy of Pediatric Allergy and Respiratory Diseases.