Clinical Characteristic And Risk Factors For Prognosis Of Egg Allergy In Infant And Young Children

Part Ⅰ Clinical Characteristics of egg allergy in infants and young childrenObjectiveTo explore the clinical characteristics of egg allergy in infants and young children,and to provide the basis for the diagnosis of egg allergy in children.MethodsChildren aged 0-3 years with confirmed IgE-mediated egg allergy from October 2019 to October 2021 at the outpatient clinic of the Capital Institute of Pediatrics,regardless of gender,were sequentially included for questionnaire collection,including demographic characteristics,clinical history,personal history and family history;routine blood tests,serum-specific IgE tests,skin prick tests and egg protein fraction tests were completed;the clinical characteristics of the enrolled children were summarized and analyzed by combining the above baseline data.Results1.A total of 119 children with egg allergy were enrolled,74 males(74/119,62.2%)and 45 females(45/119,37.8%).The mean age was(16.3± 13.6)months;the mean age of first egg allergy was(7.2 ± 3.3)months,with statistically significant differences between the male and female ratios in the different age groups(P<0.05);2.107 children(107/119,90%)developed typical allergic symptoms after first ingestion of eggs or its products,59(59/119,49.6%)after skin contact and 13(13/119,10.9%)after ingestion of breast milk(the mother’s diet did not avoid eggs).The fastest onset of symptoms was by skin contact,followed by direct ingestion of eggs or egg products,with statistically significant differences between groups(p<0.01);3.Skin symptoms were the most common clinical manifestation,followed by gastrointestinal,respiratory and neurological symptoms;34 children had had at least one egg-induced anaphylaxis;4.116 children had a previous history of eczema,45 had a history of wheezing,71 had a history of rhinitis and 97 had a history of other food allergies;95 children had a family history of allergic diseases;5.The baseline tIgE level was 493(47.4,792.5)kU/L and the baseline egg white sIgE level was 10.5(0.82-57.8)kUA/L,of which 31(26.1%)were mildly sensitized,44(37%)were moderately sensitized and 44(37%)were severely sensitized;89 children underwent egg SPT,of which 81(91%)were positive.The baseline value of the head of wind was 8.5(3.0,13.0)mm and the baseline value of the length of redness was 19.0(10.0,31.0).6.Ovomucin(Gal d 1)positivity was 63.9%with a baseline mean level of 5.4± 13.7 IU/ml,ovalbumin(Gal d 2)positivity was 89.9%with a baseline mean level of 10.2± 17.4 IU/ml and lysozyme(Gal d 4)positivity was 29.4%with a baseline mean level of 3.7±7.9 IU/ml.7.There was a significant correlation between the baseline levels of serum sIgE,SPT and CRD tests and the severity of clinical symptoms(p<0.05).ConclusionThe onset of egg allergy in infants and young children is early and rapid,mostly triggered by ingestion and exposure,and the clinical presentation is varied,with skin symptoms predominating.A high proportion of children with egg allergy have multiple food allergies,a history of other allergic diseases and family history.Serum sIgE,SPT and CRD tests are predictive of the diagnosis of egg allergy and the severity of clinical symptoms,with children with high levels of sensitisation being more likely to develop anaphylaxis.Part Ⅱ Analysis of the prognosis of egg allergy in infants and young children and its risk factorsObjectiveTo understand the outcomes of egg allergy in infants and young children 1 year after follow-up and analyze the risk factors affecting their prognosis to help their long-term clinical management.MethodsThe children enrolled were prospectively analysed for a follow-up period of 1 year and their outcomes was assessed by elimination test.The children were divided into three groups,tolerant at 6-month follow-up,tolerant at 12-month follow-up and persistently allergic,to analyse the risk factors affecting the regression of egg allergy in infants and young children.Results1.116 children completed follow-up with a mean age of(17.2± 14.1)months,of whom 72(62.1%)were male and 44(37.9%)were female,and the age of first occurrence of egg allergy was(7.3±2.9)months.the tolerance rate at the 6-month follow-up was 15.5%(18/116)and at the 12-month follow-up was 40.5%(47/116);2.Cox risk regression multifactorial analysis showed that initial onset involved multiple systems(HR=5.1,95%CI:2.3-12.4,P<0.05),previous history of egg-induced anaphylaxis(HR=4.1,95%CI:1.3-11.2,P<0.05),history of wheezing(HR=2.5,95%CI:1.1-72.3,P<0.05),time to introduction of solid complementary foods>6 months(HR=2.9,95%CI:1.2-7.2,P<0.05),size of egg SPT wind mass diameter(HR=2.7,95%CI:1.1-7.5,P<0.05)and Gal d 1 baseline sIgE(HR=2.4,95%CI:1.3-9.9)were the independent risk factors for persistent egg allergy in children 1 year after diagnosis.Conclusion15.5%of the children with egg allergy were tolerant after 6 months of enrolment and 40.5%after 12 months of enrolment;multi-system involvement at first onset,previous history of egg-induced anaphylaxis,history of wheezing,introduction of solid complementary foods>6 months,size of egg SPT wind mass diameter and Gal d 1 baseline sIgE were the independent risk factors for persistent egg allergy 1 year after diagnosis.