Natural history and risk factors of IgE-mediated cow's milk protein allergy in infants / 中华儿科杂志

Objective: To investigate the natural history and risk factors for continued allergy in infants with IgE-mediated cow's milk protein allergy (CMPA). Methods: This was a prospective cohort study that included 72 infants under 24 months of age diagnosed with IgE-mediated CMPA in the allergy clinic of the Children's Hospital, Capital Institute of Pediatrics from October 2019 to November 2020. General information, clinical manifestations, serum total IgE, cow's milk specific IgE, and cow's milk protein component specific IgE were collected. Follow-ups were conducted at 24 and 36 months of age, and the patients were divided into the persistent allergy group and the tolerance group based on whether they developed cow's milk tolerance at 36 months of age. Mann-Whitney U test, chi-square test, and binary Logistic regression were used for intergroup comparison and multivariate analysis. Results: Among the 72 CMPA children, there were 42 boys and 30 girls, with an age of 10 (7, 15) months at enrollment. Cow's milk protein tolerance was observed in 32 cases (44%) and 46 cases (64%) at 24 and 36 months of age, respectively. There were 26 cases in the persistent allergy group and 46 cases in the tolerance group. The proportion of respiratory symptoms, history of wheezing, positive specific IgE for α-lactalbumin and the total IgE level in the persistent allergy group were higher than that in the tolerance group (7 cases (27%) vs. 0, 6 cases (23%) vs. 2 cases (4%), 67% (14/21) vs. 26% (10/39), 225 (151, 616) vs. 48 (21, 185) kU/L, χ2=10.82, 4.16, 9.57, Z=4.07, all P<0.05). Multivariate Logistic regression analysis showed that anaphylaxis (OR=21.14, 95%CI 2.55-175.14, P=0.005), a history of allergic rhinitis (OR=5.94, 95%CI 1.54-22.86, P=0.005), elevated milk specific IgE (OR=1.04, 95%CI 1.01-1.08, P=0.024), and positive casein specific IgE (OR=6.64, 95%CI 1.39-31.69, P=0.018) were risk factors for continuous CMPA. Conclusions: Most infants with IgE-mediated CMPA can achieve tolerance within 3 years. Anaphylaxis, a history of allergic rhinitis, elevated milk specific IgE levels, and casein sensitization are risk factors for continuous allergy.

Clinical characteristics of IgE-mediated cow's milk protein allergy in children / 中华儿科杂志

Objective: To analyze the clinical features of IgE-mediated cow's milk protein allergy (CMPA) in children aged 0-5 years. Methods: This cross-sectional study collected the data on children diagnosed with CMPA in the Department of Allergy at the Children's Hospital of the Capital Institute of Pediatrics from October 2019 to November 2020 and improved peripheral blood routine,total IgE defection, milk specific IgE (sIgE) defection,SPT and milk component defection,diagnosis of severe anaphylaxis based on clinical manifestations. Rank-sum test and chi-square test are used for statistical analysis of clinical characteristics between groups. Results: A total of 106 children (67 boys and 39 girls) were enrolled with the age of 15 (8, 34) months, including 42 cases (≤ 1 year of age), 39 cases (>1-<3 years of age) and 25 cases(≥3 years of age), the onset age of 6 (5, 8) months. Among them, 95 cases (89.6%) were reacted after consuming milk or its products, 42 cases (39.6%) had reaction due to skin contact and 11 cases (10.4%) reacted after exclusive breastfeeding. The onset time of milk product consumption was 45 (1, 120) min, skin contact pathway was 10 (5, 30) min and symptoms in breastfeeding pathway was 121 (61, 180) min. There was statistical difference among the time of symptoms (χ2=77.01, P<0.001).The cutaneous reaction was most common (100 cases, 94.3%), followed by digestive (20 cases, 18.9%) and respiratory (16 cases, 15.1%), and the nervous symptoms (1 case, 0.9%) were uncommon and 24 cases (22.6%) had at least one episode of anaphylaxis. There were 87 cases (82.1%) also diagnosed with other food allergies, 94 cases (88.7%) with previous eczema, 57 cases (53.8%) with history of rhinitis, and 23 cases (21.7%) with history of wheezing. The total IgE level was 191.01 (64.71, 506.80) kU/L, and the cow's milk sIgE level was 3.03 (1.11, 15.24) kU/L. The maximum diameter of the wheal in SPT was 8.2 (4.0, 12.0) mm. Component resolved diagnosis showed that 77 cases (81.9%) were sensitized to at least one out of 4 main components, including casein, α lactalbumin, β lactoglobulin and bovine serum albumin.The possibility of anaphylaxis in children with milk sIgE grade Ⅳ-Ⅵ was higher than that in children with grade 0-Ⅲ (57.7% (15/26) vs. 12.5% (10/80), OR=9.545, 95%CI 3.435-26.523). Children with milk SPT ≥+++ had a higher probability of anaphylaxis than those with milk SPT ≤++ (34.4% (11/32) vs. 11.5% (3/26), OR=4.016, 95%CI 0.983-16.400). Anaphylaxis were more common in α lactalbumin positive children than in negative children (34.3% (13/38) vs. 14.2% (8/56), χ2=1.23，P=0.042). Conclusions: CMPA in children has early onset and diversified clinical manifestations, which are mainly cutaneous symptoms. Most children are sensitized to at least one allergen component. Serum sIgE level, SPT reaction and allergen components play important roles in the diagnosis and evaluation of CMPA, and higher milk sIgE level may predict a higher risk of anaphylaxis.