Genetic predictors of celiac disease, lactose intolerance, and vitamin D function and presence of peptide morphins in urine of children with neurodevelopmental disorders

Serum binding folate receptor autoantibodies lower in autistic boys and positively-correlated with folate

Folate receptor autoantibody (FRAA) has caught increasing attention since its discovery in biological fluids of patients with autism spectrum disorder (ASD), but quantification and understanding of its function are still in their infancy. In this study, we aimed to quantify serum binding-FRAA and explore its relation with serum folate, vitamin B12 (VB12) and ferritin. We quantitated serum binding-FRAA in 132 ASD children and 132 typically-developing (TD) children, as well as serum levels of folate, VB12 and ferritin. The results showed that serum binding-FRAA in the ASD group was significantly lower than that in the TD group (p < 0.0001). Further analysis showed that the difference between these two groups was attributed to boys in each group, not girls. There was no statistically significant difference in folate levels between the ASD and TD groups (p > 0.05). However, there was significant difference in boys between these two groups, not girls. Additionally, the combination of nitrite and binding-FRAA showed potential diagnostic value in patients with ASD (AUC > 0.7). Moreover, in the ASD group, the level of folate was consistent with that of binding-FRAA, whereas in the TD group, the binding-FRAA level was high when the folate level was low. Altogether, these differences revealed that the low serum FRAA in autistic children was mediated by multiple factors, which deserves more comprehensive investigation with larger population and mechanistic studies.

Association of Vitamin D, Zinc and Selenium Related Genetic Variants With COVID-19 Disease Severity

Background: COVID-19 pandemic has proved to be an unrelenting health threat for more than a year now. The emerging amount of data indicates that vitamin D, zinc and selenium could be important for clinical presentation of COVID-19. Here, we investigated association of genetic variants related to the altered level and bioavailability of vitamin D, zinc and selenium with clinical severity of COVID-19. Methods: We analyzed variants in genes significant for the status of vitamin D (DHCR7/NADSYN1 rs12785878, GC rs2282679, CYP2R1 rs10741657, and VDR rs2228570), zinc (PPCDC rs2120019) and selenium (DMGDH rs17823744) in 120 Serbian adult and pediatric COVID-19 patients using allelic discrimination. Furthermore, we carried out comparative population genetic analysis among European and other worldwide populations to investigate variation in allelic frequencies of selected variants. Results: Study showed that DHCR7/NADSYN rs12785878 and CYP2R1 rs10741657 variants were associated with severe COVID-19 in adults (p = 0.03, p = 0.017, respectively); carriers of DHCR7/NADSYN TG+GG and CYP2R1 GG genotypes had 0.21 and 5.9 the odds for developing severe disease, OR 0.21 (0.05-0.9) and OR 5.9 (1.4-25.2), respectively. There were no associations between selected genetic variants and disease severity in pediatric patients. Comparative population genetic analysis revealed that Serbian population had the lowest frequency of CYP2R1 rs10741657 G allele compared to other non-Finish Europeans (0.58 compared to 0.69 and 0.66 in Spanish and Italian population, respectively), suggesting that other populations should also investigate the relationship of CYP2R1 variant and the COVID-19 disease course. Conclusion: The results of the study indicated that vitamin D related genetic variants were implicated in severe COVID-19 in adults. This could direct prevention strategies based on population specific nutrigenetic profiles.

Measures of gluten-related reactivity in children with autism spectrum disorders in the absence of overt gastrointestinal symptoms: a pilot study from the United Arab Emirates

Objectives

The aetiology of autism spectrum disorder (ASD) is multifactorial, sometimes genetic, and may be associated with abnormal immunological responses to peptides from proteins such as gluten. These peptides may cross the blood-brain barrier and affect neurotransmission, resulting in behavioural symptoms consistent with ASD. The aim of this study was to screen for markers of gluten-related immune reactivity in the absence of overt gastrointestinal symptoms in patients with ASD in the United Arab Emirates, a country associated with a high prevalence of ASD but lacking this type of research.

Methods

Patients diagnosed with ASD (using Diagnostic and Statistical Manual of Mental Disorders-IV-based criteria and Autism Diagnostic Observational Schedules) were compared with controls, regarding anti-tissue transglutaminase (tTG) immunoglobulin (Ig) A and anti-deamidated gliadin peptide (DGP) IgA levels.

Results

Sixty-six patients with ASD and 101 controls were included. Patients with ASD showed statistically significant lower anti-DGP IgA levels, but no significant difference in anti-tTG IgA levels, versus healthy controls. Correlations between immunological data and clinical symptoms were synergistic, but not statistically significant.

Conclusion

ASD may be associated with reduced levels of anti-DGP IgA.

Psychiatric Manifestations of Coeliac Disease, a Systematic Review and Meta-Analysis

Background: Coeliac disease (CD) is increasingly prevalent and is associated with both gastrointestinal (GI) and extra-intestinal manifestations. Psychiatric disorders are amongst extra-intestinal manifestations proposed. The relationship between CD and such psychiatric disorders is not well recognised or understood. Aim: The aim of this systematic review and meta-analysis was to provide a greater understanding of the existing evidence and theories surrounding psychiatric manifestations of CD. Methodology: An online literature search using PubMed was conducted, the prevalence data for both CD and psychiatric disorders was extracted from eligible articles. Meta analyses on odds ratios were also performed. Results: A total of 37 articles were included in this review. A significant increase in risk was detected for autistic spectrum disorder (OR 1.53, 95% CI 1.24–1.88, p < 0.0001), attention deficit hyperactivity disorder (OR 1.39, 95% CI 1.18–1.63, p < 0.0001), depression (OR 2.17, 95% CI 2.17–11.15, p < 0.0001), anxiety (OR 6.03, 95% CI 2.22–16.35, p < 0.0001), and eating disorders (OR 1.62, 95% CI 1.37–1.91, p < 0.00001) amongst the CD population compared to healthy controls. No significant differences were found for bipolar disorder (OR 2.35, 95% CI 2.29–19.21, p = 0.43) or schizophrenia (OR 0.46, 95% CI 0.02–10.18, p = 0.62). Conclusion: CD is associated with an increased risk of depression, anxiety, eating disorders as well as ASD and ADHD. More research is required to investigate specific biological explanations as well as any effect of gluten free diet.

HLA-DQ Genotyping, Duodenal Histology, and Response to Exclusion Diet in Autistic Children With Gastrointestinal Symptoms

OBJECTIVES

A correlation between autism spectrum disorders (ASDs) and gastrointestinal (GI) problems, and a possible link between gluten consumption and ASD have been increasingly reported. Gluten/casein-free diet (GCFD) is often undertaken, with conflicting results. This study aimed at evaluating the distribution of human leukocyte antigen (HLA)-DQ2/DQ8 typing among patients with ASD with GI symptoms, together with its correlation with duodenal histology and response to GCFD.

METHODS

Between 2002 and 2015 all patients with ASD with GI symptoms referred to our outpatient clinic, displaying clinical, laboratory, or ultrasound findings suggestive of organic disease, underwent endoscopy, celiac disease (CD) serum antibodies testing and HLA-DQ2/DQ8 genotyping. Patients were prescribed a 6-month GCFD, and then clinically reassessed.

RESULTS

Among 151 enrolled patients, 134 (89%) were negative for CD-specific antibodies; 72 (48%) were positive for HLA-DQ2/DQ8; and 56 (37%) showed duodenal microscopic inflammation. Clinical improvement was observed in non-CD patients irrespective of the rigorous or partial adherence to the diet, being the difference nonstatistically significant. Response to diet was related to the presence of histological duodenal alterations at baseline (odds ratio 11.323, 95% confidence interval 1.386-92.549 for Marsh 2 pattern), but not to HLA-DQ2/DQ8 positivity (odds ratio 1.120, 95% confidence interval 0.462-2.716).

CONCLUSIONS

Our data suggest that children with ASD with GI symptoms have a high prevalence of duodenal intraepithelial lymphocytic infiltration, which seems to be linked to a mechanism other than autoimmune response to gluten consumption. Alteration of duodenal histology, but not the HLA-DQ2/DQ8 status, was associated with clinical response to the diet.