Is perceived intolerance to milk and wheat associated with the corresponding IgG and IgA food antibodies? A cross sectional study in subjects with morbid obesity and gastrointestinal symptoms

Association between Food-Specific Immunoglobulin G4 Antibodies in Adults with Self-Reported Signs and Symptoms Attributed to Adverse Reactions to Foodstuffs

Signs and symptoms attributed to adverse reactions to foodstuffs (ARFS) need tools for research and evaluation in clinical practice. The objectives of this study were (a) to evaluate the most frequent self-reported signs and symptoms attributed to ARFS in Spanish adults, (b) to determine the prevalence of food-specific IgG4 antibody reactions (AbRs), and (c) to investigate the association between self-reported ARFS symptomatology and food-specific IgG4 AbRs. Food-specific IgG4 AbRs against 57 common food and beverages (AESKUCARE-T2FA® in vitro point-of-care test kit, Aesku.Diagnostics GmbH, Germany) were determined in capillary blood samples of 205 volunteers living in the Region of Madrid (Spain). The most frequent self-reported signs and symptoms were related to skin (43%), digestive (41%), and nervous system (NS, 33%) problems. The prevalence of food-specific IgG4 AbRs was cow's milk (73%), sheep's milk (70%), casein (66%), and goat's milk (56.10%). Positive IgG4 AbRs against tomato had a profile consisting of 3/4 of skin problems, more than half of digestive, and 2/5 of NS self-reported signs and symptoms. In conclusion, at least 1/3 of the studied sample reported skin, digestive, and NS signs and symptoms. The most frequent food-specific IgG4 AbRs were related to dairy. Skin problems were more frequent in positive tomato IgG4 AbRs.

Specific Immunoglobulin E and G to Common Food Antigens and Increased Serum Zonulin in IBS Patients: A Single-Center Bulgarian Study

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder whose pathogenesis is considered multifactorial, including abnormal gut motility, visceral hyperreactivity, psychological factors, disturbances in the brain-gut axis, leaky gut, oxidative stress, etc. We aimed to investigate serum levels of specific immunoglobulin E and G to common food antigens and zonulin and to assess their use in clinical practice for patients with IBS. Material and methods. We included 23 participants, 15 with IBS (diagnosed according to the Rome IV criteria) and 8 healthy controls. We investigated serum levels of specific IgG antibodies to 24 food antigens, specific IgE antibodies to 20 food antigens, anti-celiac antibodies, fecal calprotectin and serum zonulin by ELISA. Results. Food-specific positive IgG antibodies were significantly higher in patients with IBS than in controls (p = 0.007). IgE-mediated allergic reactions were found in five patients with IBS; no one had anti-TG antibodies. One-third of IBS patients demonstrated a low degree of chronic inflammation (positive fecal calprotectin test > 50 ng/mL) without specific bacterial infection. Serum levels of zonulin in IBS patients were higher than in healthy controls (0.378 ± 0.13 vs. 0.250 ± 0.14 ng/mL, p = 0.0315). However, no correlations between clinical symptoms and zonulin levels were found. Conclusion. The mechanisms of IgG hypersensitivity and low degree inflammation in IBS and elevated zonulin may contribute to multifactor pathogenesis in IBS.

Food Allergy: Unproven diagnostics and therapeutics

Food allergy or intolerance is often attributed by patients as the cause of many symptoms unknown to be directly related to food ingestion. For immunoglobulin E (IgE) mediated food allergy, diagnostic modalities are currently limited to the combination of clinical history, evidence of sensitization with food-specific IgE testing and skin-prick testing, and oral food challenge. Many patients find an appeal in the promise of identification of the etiology of their symptoms through alternative food allergy or intolerance diagnostic modalities. These patients may seek guidance from allergists or their general providers as to the legitimacy of these tests or interpretation of results. These tests include food-specific serum IgG or IgG4 testing, flow cytometry to measure the change in leukocyte volume after exposure to food, intradermal or sublingual provocation-neutralization, electrodermal testing, applied kinesiology, hair analysis, and iridology. In addition, there are some unconventional therapeutic modalities for adverse reactions to foods, including rotary diets. None of these have been supported by scientific evidence, and some even carry the risk of severe adverse reactions. It is important that we offer our patients evidence-based, accurate counseling of these unproven modalities by understanding their methods, their paucity of credible scientific support, and their associated risks.

Study on Aberrant Eating Behaviors, Food Intolerance, and Stereotyped Behaviors in Autism Spectrum Disorder

Objective: To investigate the aberrant eating behaviors (EBs), gastrointestinal (GI) symptoms, and food intolerance in children with autism spectrum disorder (ASD) and their association with clinical core symptoms of ASD. Method: A total of 94 preschool children with ASD treated at the Child Mental Health Research Center of Nanjing Brain Hospital between October 2016 and April 2018 were enrolled. In addition, 90 children with typical development (TD) in the community during the same period were recruited. The conditions of aberrant EBs and GI symptoms in children were investigated using questionnaire surveys. Serum specific IgG antibodies against 14 kinds of food were detected using enzyme-linked immunosorbent assays (ELISAs). Results: The detection rate of aberrant EBs in the ASD group was significantly higher than that in the TD group (67.39 vs. 34.94%), and the rate of GI symptoms was also higher in the ASD group than that in the TD group (80.22 vs. 42.11%). Detection of food intolerance in children with ASD showed that the positive rate was 89.89% and that the majority of children had multiple food intolerances. The correlation analysis results showed that the severity of aberrant EBs positively correlated with stereotyped behavior of children with ASD (r = 0.21, P = 0.04) and that food-specific IgG antibodies concentrations positively correlated with high-level stereotyped behavior in children with ASD (r = 0.23, P = 0.03). Conclusion: ASD with aberrant EBs or high food-specific IgG antibodies concentrations had more severe stereotyped behavior, which may have implications for exploring the immune mechanism of ASD. Clinical Trial Registration: ChiCTR-RPC-16008139.