Purpose: This study aimed to evaluate the feasibility, safety, and immunological outcomes of low-dose cow’s milk oral immunotherapy (CM OIT) in school-aged children and adolescents with severe, persistent cow’s milk allergy (CMA), a group typically considered at a high risk for OIT. Methods: We conducted a retrospective study involving 12 patients (median age, 11.4 years) with immunoglobulin E (IgE)-mediated CMA, who underwent individualized low-dose CM OIT in the outpatient setting at a single tertiary hospital. Baseline and longitudinal clinical and immunological data, including casein-specific IgE and immunoglobulin G4 (IgG4) levels, were analyzed. Patients were classified as either desensitized or unsuccessful based on treatment outcomes. Results: Of the 12 patients with severe CMA, 6 achieved desensitization up to the target dose, while the remaining 6 discontinued treatment because of intolerance or poor adherence. The desensitized and unsuccessful groups showed no significant differences in baseline age, OIT starting dose, or serum casein-specific IgE level. Immunological evaluation revealed a significantly greater increase in serum casein-specific IgG4 (0.87 vs. -0.37 mg/L, P = 0.004) and a significantly lower natural log-transformed fold change in the IgE/IgG4 ratio (-1.38 vs. 0.44, P = 0.008) in the desensitized group. None of the patients required epinephrine during OIT, and adverse events were generally mild. Conclusion In selected high-risk pediatric populations with severe CMA, outpatient-based low-dose OIT using individualized flexible protocols may provide a relatively safe approach that improves tolerability and adherence. Increased casein-specific IgG4 levels and a reduced casein-specific IgE/IgG4 ratio may serve as valuable biomarkers for treatment response.

Background: Precautionary allergen labeling (PAL) is mandatory and legally regulated in Korea. This study aims to investigate the frequency of PAL use in food products, evaluate its competence, and seek direction for improvement. Methods: Cow’s milk (CM) and hen’s egg white (EW) protein concentrations were measured using an enzyme-linked immunosorbent assay (ELISA). The results validated PAL using the Voluntary Incidental Trace Allergen Labeling ® 3.0 program. A survey was conducted on guardians to compare preferences and understanding of the current and the arbitrarily revised PAL. Results: PAL was used in 91.8% (280/305) of baby food products. ELISA results using randomly selected baby food products showed that only 16.7% (5/30; No PAL with no contamination, n = 4; PAL with real-contamination risk, n = 1) were validated to PAL. A detectable CM was found in two products (2/26, 7.7%), with one product exceeding the reference dose (10.3 ± 0.17 ppm). EW was not detected at all (0/16). A total of 207 surveys from guardians were collected and categorized into three groups: food allergy (FA, n = 103), diseases other than food allergies (Others, n = 52), and no disease (Control, n = 52). The FA group exhibited the highest frequency of checking food allergen labeling (“always”: 78.6%, “often”: 9.7%), with a similar PAL adherence (“always”: 58.3%, “often”: 10.4%). None of the groups were satisfied with the current PAL. The ‘allergen-free’ statement was mostly preferred across all groups. The FA group notably preferred PAL with concentration statements. Conclusion PAL is excessively prevalent and insufficient in ensuring the safety of children with FAs, necessitating a revision towards a more patient-friendly, evidence-based system for affected individuals and their families.

Background: There is increasing evidence that probiotics are effective in treating allergic rhinitis (AR), while some controversies remain. This study was performed to evaluate the therapeutic effect and safety of a mixture of Bifidobacterium longum and Lactobacillus plantarum (NVP-1703) in children with AR. Methods: In a randomized, double-blind, placebo-controlled study, children aged 6 to 19 years with perennial AR were treated with NVP-1703 at a dose of 1 × 1010 CFU/day or placebo once a day for 4 weeks. Total nasal symptom score (TNSS), nasal symptom duration score (NSDS), quality of life (QoL), allergic inflammatory markers, and safety parameters were evaluated. Results: After 4 weeks of treatment, the TNSS in the NVP-1703 group significantly decreased compared to that in the placebo group (P = 0.011), both in the morning and the evening (P = 0.031 and P = 0.004, respectively). The NSDS also significantly decreased in the NVP-1703 group compared to that in the placebo group (P = 0.018). QoL scores, particularly those related to mouth breathing and itchy nose, showed a significant improvement in the NVP-1703 group compared to the placebo group. The ratios of interleukin (IL)-4/IL-22 and IL-5/IL-22 were significantly reduced in the NVP-1703 group after the treatment compared to the baseline values. No notable adverse events were reported in the NVP-1703 group. Conclusion Oral administration of a mixture of B. longum and L. plantarum (NVP-1703) improved both AR symptoms and QoL in children with perennial AR, accompanied by decreases in the ratios of T helper 2 cytokines to IL-22.

Purpose: Fish allergy is rare in children, and there have been few studies on childhood fish allergy. This study aims to investigate the clinical characteristics and laboratory findings of white meat fish (WMF) allergy in Korean children. Methods: In this study, we enrolled 150 children with a history of WMF consumption who underwent serum specific immunoglobulin E to cod (cod-sIgE) at Ajou University Hospital from January 2019 to December 2022. The demographic characteristics, clinical symptoms, history of consuming 6 major Korean WMF (cod, cutlass, yellow croaker, brown sole, olive flounder, and anchovy), and cod-sIgE were investigated. Results: Sixty-five subjects (43.3%) had clinical responses to at least 1 of the 6 WMF (WMF-allergic), and 85 subjects had no allergic reaction to all 6 WMF (WMF-tolerant). The median age of first symptom onset in the WMF-allergic group was 15 months. Major causative WMF were yellow croaker (30.6%), cutlass (28.7%), cod (26.1%), brown sole (20.4%), anchovy (14.7%), and olive flounder (6.5%). Twenty-three of 65 WMF-allergic children (35.4%) had anaphylaxis. The median level of cod-sIgE was 4.61 kUA/L (range, 0.04–100.10 kUA/L) in the WMF-allergic group, and this value was significantly higher (P < 0.001) than that of the WMF-tolerant group (0.04 kUA/L; range, 0.04–3.08 kUA/L). The positive rates ( ≥ class 2, 0.7 kUA/L) of cod-sIgE for the 6 individual WMF ranged from 69% to 90%. Conclusion We propose that WMF allergy can develop in young children, with 35.4% experiencing anaphylaxis. Cod-sIgE is considered a useful tool for diagnosing not only cod allergy but also other WMF allergy in children.

Purpose: Fish allergy is the ninth common food allergy, and cutlassfish is one of the common allergenic fishes in Korean children.However, there is no commercial diagnostic tool for testing cutlassfish allergy in the world. We evaluated the usefulness of serum cod specific IgE (cod-sIgE) to diagnose cutlassfish allergy and cross-reaction between cutlassfish and cod. Methods: Nineteen children who experienced immediate type reactions after consumption of cutlassfish were enrolled. Cod-sIgE was measured by ImmunoCAP, and serum samples were obtained from 11 allergic patients and 11 controls. Using our own homemade crude extracts, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), anti-parvalbumin (PV) immunoglobulin G immunoblot, enzyme-linked immunosorbent assay (ELISA), and ELISA inhibition were performed. Results: Thirteen patients were clinically allergic to both cutlassfish and cod, and 6 were allergic to cutlassfish alone. The median age and cod-sIgE concentrations were not significantly different between the 2 groups. The clear fish protein bands and PVs were identified on SDS-PAGE and immunoblotting. Serum cod-sIgE was positive in 4 out of 6 cutlassfish mono-allergic patients, however, there was no significant correlation between cod-sIgE by ImmunoCAP and cutlassfish-specific IgE by ELISA. The cutlassfish IgE ELISA was profoundly inhibited by cutlassfish, while the cod IgE ELISA was profoundly inhibited by cod but partially inhibited by cutlassfish. Conclusion We found a potential diagnostic value of cod-sIgE to diagnose cutlassfish allergy and the asymmetric cross-reaction between cutlassfish and cod. These results could help diagnose and provide a dietary guidance in cutlassfish allergic children.

Background: Hen’s egg white (HEW) is the most common cause of food allergy in children which induces mild to fatal reactions. The consultation for a proper restriction is important in HEW allergy. We aimed to identify the changes in HEW allergenicity using diverse cooking methods commonly used in Korean dishes. Methods: Crude extract of raw and 4 types of cooked HEW extracts were produced and used for sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE), enzyme-linked immunosorbent assay (ELISA), and ELISA inhibition assays using 45 serum samples from HEW allergic and tolerant children. Extracts were prepared; scrambled without oil for 20–30 seconds in frying pan without oil, boiled at 100°C for 15 minutes, short-baked at 180°C for 20 minutes, and long-baked at 45°C for 12 hours with a gradual increase in temperature up to 110°C for additional 12 hours, respectively. Results: In SDS-PAGE, the intensity of bands of 50–54 kDa decreased by boiling and baking.All bands almost disappeared in long-baked eggs. The intensity of the ovalbumin (OVA) immunoglobulin E (IgE) bands did not change after scrambling; however, an evident decrease was observed in boiled egg white (EW). In contrast, ovomucoid (OM) IgE bands were darker and wider after scrambling and boiling. The IgE binding reactivity to all EW allergens were weakened in short-baked EW and considerably diminished in long-baked EW. In individual ELISA analysis using OVA+OM+ serum samples, the median of specific IgE optical density values was 0.435 in raw EW, 0.476 in scrambled EW, and 0.487 in boiled EW. Conversely, it was significantly decreased in short-baked (0.406) and long-baked EW (0.012). Significant inhibition was observed by four inhibitors such as raw, scrambled, boiled and short-baked HEW, but there was no significant inhibition by long-baked HEW (IC50 > 100 mg/mL). Conclusion We identified minimally reduced allergenicity in scrambled EW and extensively decreased allergenicity in long-baked EW comparing to boiled and short-baked EW as well as raw EW. By applying the results of this study, we would be able to provide safer dietary guidence with higher quality to egg allergic children.