Three-year prognosis after low-dose oral food challenge for children with wheat allergy.

BACKGROUND: Low-dose oral food challenge (LD-OFC) is an approach to avoid complete elimination in high-risk patients with wheat allergy (WA). We examined the 3-year prognosis after LD-OFC among patients who passed and failed LD-OFC. METHODS: Children with immediate-type WA aged ≤6 years with a history of reaction to ≤390 mg of wheat protein underwent their first LD-OFC with 52 mg (baseline LD-OFC). After passing the LD-OFC, children stepped up to 390, 1300, and 5200 mg step-by-step every 3-6 months. After failing LD-OFC, children repeated LD-OFC every 6-12 months. We assessed wheat tolerance defined as consuming 5200 mg without symptoms for 3 years after baseline LD-OFC. RESULTS: The median age of 124 children was 2.4 years, and the wheat- and ω-5-gliadin-specific immunoglobulin E (IgE) levels (kUA/L) were 23.6 and 2.1, respectively. Upon baseline LD-OFC, 57% passed (LD-tolerant), whereas 43% failed (LD-reactive). Within 3 years, 38% of the LD-reactive group passed re-administered LD-OFC, and 70% of all participants avoided complete elimination. The percentage of the participants who became capable of consuming 390 mg (87% vs. 18%), 1300 mg (78% vs. 13%), and acquired tolerance (70% vs. 13%) was significantly higher in the LD-tolerant group than in the LD-reactive group (p < 0.001). Predictors of persistent WA in the LD-tolerant group were older age (adjusted odds ratio, 1.63), ω-5-gliadin-specific IgE level (1.62 per 10-fold increase), and other food allergies (1.94). CONCLUSIONS: LD-tolerant patients frequently acquired wheat tolerance within 3 years. Even if once positive, one-third could pass the re-administered LD-OFC within 3 years.

Long-term follow-up of fixed low-dose oral immunotherapy for children with severe cow's milk allergy.

BACKGROUND: The efficacy and safety of cow's milk (CM) low-dose oral immunotherapy (LOIT) at one-year follow-up have been previously reported. We investigated the outcome of fixed long-term LOIT in children with severe CM allergy. METHODS: Children with positive reactions to oral food challenge (OFC) with 3 mL CM were included. The LOIT group (n = 33) ingested up to 3 mL CM for 1 year. After a two-week CM avoidance, 3 and 25 mL OFCs were performed. Children with positive reactions continued with 3 mL ingestion, with OFCs repeated yearly. Regular home consumption of 25 mL CM after passing the OFCs was defined as 25 mL short-term unresponsiveness (25 mL STU). The historical control group (n = 16) with reactions to 3 mL OFC eliminated daily CM ingestion. RESULTS: The proportion of 25 mL STU in the LOIT group was 27%, 52%, and 61% after 1, 2, and 3 years, respectively, and the 3-year percentage was significantly higher than that in the historical control group (13%, P = .002). In the LOIT group, only one child developed severe symptoms. Furthermore, in this group, CM- and casein-specific immunoglobulin E (sIgE) levels decreased significantly and casein-specific IgG and IgG4 levels increased significantly after 3 years, whereas the historical control group presented no significant change in these parameters. Baseline sIgE levels were significantly low in children achieving 25 mL STU. CONCLUSION: Continued fixed LOIT yields immunologic improvement and may be effective and safe for severe CM allergy.

Safe egg yolk consumption after a negative result for low-dose egg oral food challenge.

BACKGROUND: Hen's egg is one of the most common allergens causing infantile food allergy. Consuming heated egg yolk slightly contaminated with egg white (EY with scEW) improves diet quality. Most children with egg allergies can safely consume 1/25 of a heated whole egg (low-dose egg). Although low-dose egg has similar antigenicity to EY with scEW, clinical reproducibility is unknown. We aimed to examine the safety of EY with scEW consumption after a negative result of low-dose egg oral food challenge (OFC). METHODS: In this prospective study, children aged <18 years with a history of immediate reaction to eggs were enrolled. We advised children and guardians to consume EY with scEW after a negative result of low-dose egg OFC and to record symptoms, if any. RESULTS: We evaluated 276 children with negative results for low-dose egg OFC who had previously shown reactivity to eggs. Their median age was 1.2 years. Boys accounted for 188 (68%) of the children. The median egg white-specific immunoglobulin E level was 11.7 kUA /L. At home, six children experienced mild symptoms. Skin symptoms were the most common. Among the six children, five were confirmed to continue the consumption of EY with scEW and one developed mild respiratory symptoms and continued to avoid eating eggs. CONCLUSION: Although a few children with egg allergies experience mild symptoms, most of them can ultimately consume EY with scEW. Consumption of EY with scEW after low-dose egg OFC seems safe and may improve their quality of life by making egg yolk products available.

A randomized trial of oral immunotherapy for pediatric cow's milk-induced anaphylaxis: Heated vs unheated milk.

BACKGROUND: Severe reactions may develop during cow's milk (CM) oral immunotherapy (OIT). We investigated the safety and efficacy of low-dose OIT with heated milk (HM) or unheated milk (UM) in children with anaphylaxis. METHODS: Children with symptom onset after ingestion of 3-mL HM on a double-blind, placebo-controlled food challenge were randomly assigned to the HM (n = 17) or UM (n = 16) group. HM group ingested milk powder heated at 125°C for 30 seconds, whereas the UM group used UM. Patients were hospitalized for 5 days; the HM or UM was gradually increased to 3 mL/day; 3-mL/day ingestion was continued at home. One year later, the patients underwent 2-day consecutive 3- and 25-mL HM-oral food challenges (OFCs) after 2-week avoidance. RESULTS: At baseline, milk- and casein-specific immunoglobulin E (IgE) levels were 56.0 and 51.4 kUA/L in the HM group, and 55.2 and 65.6 kUA/L in the UM group, respectively. One year later, 35% and 18% in the HM group and 50% and 31% in UM group passed the 3 and 25 mL OFCs, respectively. Rates of moderate or severe symptoms and respiratory symptoms per home dose were significantly lower in the HM than in the UM group (0.7% and 1.2% vs 1.4% and 2.6%, respectively, P < .001). ß-lactoglobulin-specific IgG4 levels significantly increased from baseline only in the UM group, whereas casein-specific IgG4 levels significantly increased from baseline in both groups. CONCLUSIONS: HM-OIT induced immunological changes more safely than the UM-OIT. The possibility of lower treatment efficacy with HM-OIT needs to be evaluated in larger studies.

Formation of IgE-Allergen-CD23 Complex Changes in Children Treated with Subcutaneous Immunotherapy for Japanese Cedar Pollinosis.

BACKGROUND: Subcutaneous immunotherapy (SCIT) is used to treat Japanese cedar (JC) pollinosis. The formation of IgE-allergen-CD23 complex after SCIT for JC pollinosis has not yet been fully elucidated. OBJECTIVE: The objective of this study was to investigate the formation of IgE-allergen-CD23 complex after SCIT for JC pollinosis. METHODS: Eleven patients were treated with 3-year SCIT for JC pollinosis at Sa-gamihara National Hospital from 2013 to 2014. Nasal and ocular symptoms (in terms of symptom scores) during the scattering of JC pollen and immunological changes were investigated. Levels of JC pollen-specific antibodies (IgE and IgG4) were measured by ImmunoCAP assays. To detect the changes in allergen-presenting ability of B cells, the levels of IgE-allergen-CD23 complexes in serum were measured by a cell-free, enzyme-linked immunosorbent-facilitated antigen-binding assay. RESULTS: The median (interquartile range) age of the subjects was 8 (6-10) years. Three patients (27%) had comorbid atopic dermatitis, and 5 patients (45%) had comorbid bronchial asthma. Before starting SCIT, the total IgE level was 373 (75-2,870) kU/L, and the level of JC pollen-specific IgE was 77.2 (15.4-528) kUA/L. Symptom scores improved significantly from the year after treatment. JC pollen-specific IgE levels did not change after 3 years of treatment. JC pollen-specific IgG4 levels increased significantly throughout the treatment period. The levels of IgE-allergen-CD23 complexes decreased significantly after 3 years of treatment. CONCLUSION: The ability of IgE-allergen complexes to bind to CD23 decreased after SCIT, suggesting that increasing levels of IgE-blocking antibodies, including IgG4, may play an important role in the mechanism of SCIT.

[EFFICACY, SAFETY AND IMMUNOLOGICAL RESPONSE WITH SQ HOUSE DUST MITE SUBLINGUAL IMMUNOTHERAPY-TABLET BY BODY WEIGHT IN CHILDREN].

BACKGROUND: Sublingual immunotherapy-tablet (SLIT-tablet) treatment includes the same dose regardless of the patients' age or body weight. We investigated the efficacy, safety and immunological response of SQ house dust mite (HDM) SLIT-tablet treatment in relation to body weight in children. METHODS: Total combined rhinitis score (TCRS), adverse events (AEs), adverse drug reactions (ADRs) and immunological response (IgE, IgG4) were evaluated post hoc in three subgroups (body weight < 30kg, 30-44kg, ≥ 45kg) of patients from a clinical trial for Japanese children with HDM allergic rhinitis (JapicCTI-152953). RESULTS: No apparent differences in TCRS were observed between the three subgroups. No differences in the frequency or nature of AEs were detected between the subgroups but the incidence of ADRs was decreased in the lower body weight subgroup. The most common ADRs occurred locally in the oral cavity and were categorized as mild. The levels of HDM specific IgE and IgG4 were increased compared to baseline in all subgroups. CONCLUSION: There were no influences of body weight for efficacy, safety, and immunological response in treatment with SQ HDM SLIT-tablet. These results indicated that SLIT dosage in children is same as adults without any concern in safety.

Novel insights regarding anaphylaxis in children - With a focus on prevalence, diagnosis, and treatment.

Anaphylaxis is a serious allergic reaction that occurs rapidly and causes a life-threatening response involving the whole body. This reaction often leads to difficulty in breathing and can result in death. The estimated prevalence of anaphylaxis is 0.05%-2%, which is reported to be increasing in children. Although drugs and venom are the most common causes of anaphylaxis in adults, food is the most common cause of anaphylaxis in children. An interesting association between food-dependent exercise-induced anaphylaxis (FDEIA) and oral immunotherapy (OIT) has recently been reported. A provocation test to determine the diagnostic and augmenting factors of FDEIA has been reported in recent years. Remarkably, several articles showed allergic symptoms without exercise in children with FDEIA and in those with FDEIA development after OIT. Regarding OIT, full-dose OIT poses a risk of adverse reactions, including anaphylaxis. Recent trials have shown the efficacy and safety of low-dose OIT in patients with food-induced anaphylaxis. In this review, we summarized the novel insights regarding anaphylaxis in the pediatric population.

Regular intake of cow's milk with oral immunotherapy improves statures of children with milk allergies.

BACKGROUND: Children who avoid cow's milk (CM) because of food allergy may show disturbed growth. Calcium insufficiency, in particular, was reported among those who completely avoided dairy products. We retrospectively examined whether oral immunotherapy (OIT) affected the stature of patients who had completely avoided CM owing to their severe CM allergy. METHODS: The CM-OIT group included subjects who had completely avoided milk their entire lives and were administered OIT between 2009 and 2013. The complete milk avoidance (CM-Avoid) group included subjects who were diagnosed with a CM allergy using oral food challenges between 2013 and 2014 who subsequently avoided CM completely. By examining clinical records and questionnaires, we investigated patient height changes over time. We calculated age- and sex-stratified height standard deviation scores (HtSDS) and analyzed changes in HtSDS retrospectively. The observation period was 1-2 years. To exclude pubertal growth spurts, we set the age criteria as less than 11 years in boys and less than 9 years in girls. RESULTS: We recruited 29 patients (19 boys) for the CM-OIT group and 20 (9 boys) for the CM-Avoid group. The patients' median ages at the start of the observation period were 7.5 years (6.1-9.6) for boys and 6.8 years (5.8-7.8) for girls in the CM-OIT group, and 5.4 years (5.0-7.5) for boys and 5.7 years (5.0-7.1) for girls in the CM-Avoid group. The initial HtSDS in the CM-OIT group was -0.31 (median) and increased to -0.22 (median) after OIT (p = 0.016). In contrast, there was no significant change in HtSDS for the CM-Avoid group. CONCLUSIONS: Physical growth of pediatric patients with severe CM allergies, who have avoided CM completely, could be improved by OIT for CM allergy.

Low-dose-oral immunotherapy for children with wheat-induced anaphylaxis.

BACKGROUND: Oral immunotherapy (OIT) use in patients with wheat anaphylaxis is not well studied. We assessed the efficacy of low-dose OIT for patients with wheat-induced anaphylaxis. METHODS: Eligible subjects were aged 5-18 years with a history of wheat anaphylaxis and confirmed symptoms during oral food challenge (OFC) to 53 mg of wheat protein. After admission to the hospital for a 5-day buildup phase, patients in the OIT group gradually increased wheat ingestion to 53 mg/day and then ingested 53 mg daily at home. One year later, they underwent 53- and 400-mg OFCs after OIT cessation for 2 weeks. The historical control group was defined as patients who avoided wheat during the same period. RESULTS: Median wheat- and ω-5 gliadin-specific immunoglobulin E (sIgE) levels were 293 and 7.5 kUA /L, respectively, in the OIT group (16 children). No patients dropped out. Within 1 year, 88% of patients in the OIT group reached 53 mg. After 1 year, 69% and 9% patients passed the 53-mg OFC and 25% and 0% passed the 400-mg OFC in the OIT and control groups (11 children), respectively (P = .002 and 0.07, respectively). In the OIT group, wheat- and ω-5 gliadin-sIgE levels significantly decreased to 154 and 4.1 kUA /L, respectively, at 1 year, and wheat- and ω-5 gliadin-specific IgG and IgG4 levels significantly increased at 1 month. Anaphylaxis developed 7 times and promptly improved without adrenaline. CONCLUSION: For patients with wheat anaphylaxis, low-dose OIT safely induces immunologic changes, achieves low-dose desensitization, and may allow for a 400 mg dose.

Predictors of Persistent Wheat Allergy in Children: A Retrospective Cohort Study.

BACKGROUND: Wheat allergy is the third most common food allergy that develops during infancy in Japan. To identify factors associated with persistent wheat allergy, we assessed the rate of tolerance acquisition among Japanese children aged less than 6 years with an immediate-type wheat allergy using the oral food challenge (OFC) method. METHODS: This retrospective cohort study included 83 children (born in 2005-2006) who had a history of immediate-type allergic reaction to wheat and were followed until 6 years of age. The subjects were divided to form "tolerant" (n = 55; tolerance acquired by 6 years of age) and "allergic" (n = 28; tolerance not acquired by 6 years of age) groups based on their OFC results. RESULTS: The rates of tolerance acquisition to 200 g of udon noodles at 3, 5, and 6 years of age were 20.5% (17/83), 54.2% (45/83), and 66.3% (55/83), respectively. The total number of anaphylactic reactions experienced prior to 3 years of age in response to all foods (p < 0.01) and to wheat (p = 0.043) was significantly higher in the allergic than in the tolerant group. Wheat- and ω-5 gliadin-specific immunoglobulin E (IgE) levels were significantly higher in the allergic group than in the tolerant group (p < 0.01), and wheat-specific IgE levels were more likely to increase after infancy in the allergic group. CONCLUSIONS: A history of anaphylaxis to all foods including wheat and/or a high level of wheat- or ω-5 gliadin-specific IgE antibodies were identified as risk factors for persistent wheat allergy.

Low-dose oral immunotherapy for children with anaphylactic peanut allergy in Japan.

BACKGROUND: Oral immunotherapy (OIT) is a promising treatment for persons with allergy; however, it can also cause adverse allergic reactions. In this study, we investigated the efficacy of low-dose OIT for anaphylactic peanut allergy. METHODS: Twenty-four children (median age, 9.6 years) with anaphylaxis to peanuts were hospitalized for 5 days and then gradually fed increasing amounts of peanut powder up to 133 mg/day. One year later, they underwent an oral food challenge after 2 weeks of peanut avoidance. Those who were asymptomatic after ingesting 795 mg of peanut protein were defined as having achieved sustained unresponsiveness. We measured peanut- and Ara h2-specific immunoglobulin (Ig) E, IgG, and IgG4 levels at 0, 1, 3, 6, and 12 months in the OIT group and at 0 and 12 months in the control group. RESULTS: At baseline, all children in the OIT group and 8 in the control group had a history of anaphylaxis. The median peanut-/Ara h2-specific IgE levels in the OIT and control groups were 55.4/48.6 and 58.2/38.1 kUa/L, respectively. One year later, 8 (33.3%) children in the OIT group exhibited sustained unresponsiveness, while none in the control group did. In the OIT group, the median peanut-specific IgE levels significantly increased to 194.0 kUa/L, after 1 month and then significantly decreased to 57.5 kUa/L at 12 months. Meanwhile, the median peanut- and Ara h2-specific IgG and IgG4 levels increased significantly after 1 month. CONCLUSION: Low-dose OIT induces immunological changes and has the capability of achieving sustained unresponsiveness in children with peanut anaphylaxis.

Oral food challenge using different target doses and time intervals between doses.

PURPOSE OF REVIEW: The oral food challenge (OFC) is a specific and vital tool used in clinical practice to identify the level of tolerance a person exhibits toward certain foods while diagnosing food-related allergies. OFC methods differ among countries. The aim of this review is to evaluate different target doses and determine the time interval between doses used for OFC. RECENT FINDINGS: We analyzed recent articles on target doses and time between doses, and noted that some papers reported low target doses and less time between doses. A low-dose OFC appears to be a useful strategy; a time interval of 15 min between doses is short and that of at least 1 h is appropriate. SUMMARY: Low-dose OFCs appear to be well tolerated and effective to avoid complete elimination of the consumption of foods causing allergies. For the safety of the OFC method, the time interval between doses should be more than 30 min.