Clinical signs of type 1 diabetes are associated with type 2 diabetes marker transcription factor 7-like 2 polymorphism.

AIMS/INTRODUCTION: We aimed to assess the distribution of transcription factor 7-like 2 gene TCF7L2 (rs7903146) polymorphism and to find possible associations between TCF7L2 and the characteristics of type 1 diabetes. MATERIALS AND METHODS: We studied 190 newly diagnosed type 1 diabetes patients (median age 12.7 years, range 2.0-72.5) and 246 controls (median age 23.8 years, range 1.4-81.5) for TCF7L2 single nucleotide polymorphism. We determined anti-islet autoantibodies, random C-peptide levels, diabetes associated HLA DR/DQ haplotypes and genotypes in all patients. RESULTS: There were no differences in the distribution of TCF7L2 single nucleotide polymorphism between patients and controls. However, patients with in type 1 diabetes, after adjusting for age and sex, subjects carrying C allele were at risk for a C-peptide level lower than 0.5 nmol/L (OR 5.65 [95% CI: 1.14-27.92]) and for zinc transporter 8 autoantibody positivity (5.22 [1.34-20.24]). Participants without T allele were associated with a higher level of islet antigen-2 autoantibodies (3.51 [1.49-8.27]) and zinc transporter 8 autoantibodies (2.39 [1.14-4.99]). CONCLUSIONS: The connection of TCF7L2 polymorphism with zinc transporter 8 and islet antigen-2 autoantibodies and C-peptide levels in patients supports the viewpoint that TCF7L2 is associated with the clinical signs and autoimmune characteristics of type 1 diabetes. The mechanisms of the interaction between the TCF7L2 risk genotype and anti-islet autoantibodies need to be studied further.

Maternal breast milk microbiota and immune markers in relation to subsequent development of celiac disease in offspring.

The potential impact of the composition of maternal breast milk is poorly known in children who develop celiac disease (CD). The aim of our study was to compare the microbiota composition and the concentrations of immune markers in breast milk from mothers whose offspring carried the genetic predisposition to CD, and whether they did or did not develop CD during follow-up for the first 3 years of life. Maternal breast milk samples [CD children (n = 6) and healthy children (n = 18)] were collected 3 months after delivery. Enzyme-linked immunosorbent assays were used to measure TGF-ß1, TGF-ß2, sIgA, MFG-E8 and sCD14. For microbiota analysis, next generation (Illumina) sequencing, real-time PCR and denaturing gradient gel electrophoresis were used. Phylotype abundance and the Shannon 'H' diversity index were significantly higher in breast milk samples in the CD group. There was higher prevalence of the phyla Bacteroidetes and Fusobacteria, the classes Clostridia and Fusobacteriia, and the genera Leptotrichia, Anaerococcus, Sphingomonas, Actynomyces and Akkermansia in the CD group. The immunological markers were differently associated with some Gram-negative bacterial genera and species (Chryseobacterium, Sphingobium) as well as Gram-positive species (Lactobacillus reuteri, Bifidobacterium animalis). In conclusion, the microbiota in breast milk from mothers of genetically predisposed offspring who presented CD showed a higher bacterial phylotype abundance and diversity, as well as a different bacterial composition, as compared with the mothers of unaffected offspring. These immune markers showed some associations with bacterial composition and may influence the risk for development of CD beyond early childhood.

Decreased Need for Correction Boluses with Universal Utilisation of Dual-Wave Boluses in Children with Type 1 Diabetes.

Insulin pumps offer standard (SB), square and dual-wave boluses (DWB). Few recommendations exist on how to use these dosing options. Several studies suggest that the DWB is more effective for high-fat or high-carbohydrate meals. Our objective was to test whether time in range (TIR) improves in children with type 1 diabetes (T1D) using the universal utilization of the dual-wave boluses for all evening meals regardless of the composition of the meal. This was a 28-day long prospective randomized open-label single-center crossover study. Twenty-eight children with T1DM using a Medtronic 640G pump and continuous glucose monitoring system were randomly assigned to receive either DWB or SB for all meals starting from 6:00 p.m. based solely on the food carbohydrate count. DWB was set for 50/50% with the second part extended over 2 h. After two weeks patients switched into the alternative treatment arm. TIR (3.9−10 mmol/L), time below range (TBR) (<3.9 mmol/L) and time above range (TAR) (>10 mmol/L) and sensor glucose values were measured and compared between the groups. Twenty-four children aged 7−14 years completed the study according to the study protocol. There were no statistically significant differences in mean TIR (60.9% vs. 58.8%; p = 0.3), TBR (1.6% vs. 1.7%; p = 0.7) or TAR (37.5 vs. 39%; p = 0.5) between DWB and SB groups, respectively. Subjects in the DWB treatment arm administered significantly less correction boluses between 6 p.m. and 6 a.m. compared to those in the SB group (1.2 ± 0.8 vs. 1.7 ± 0.8, respectively; p < 0.01). DWB for evening meals in which insulin is calculated solely on the food carbohydrate content did not improve TIR compared to standard bolus in children with T1D. However, DWB enabled to use significantly less correction boluses to achieve euglycemia by the morning compared to the SB.

Growth in Children with HLA-Conferred Susceptibility to Type 1 Diabetes.

The incidence of type 1 diabetes (T1D) is increasing throughout the world. This trend may be explained by the accelerator hypothesis. Our study investigated growth, its biochemical markers, and their associations with the development of diabetes-associated autoantibodies (DAAB) in 219 children with genetic risk for T1D. Subjects were divided into risk groups based on their human leukocyte antigen genotype. Children in the moderate- to high-risk group were significantly taller when corrected to mid-parental height and had a lower insulin-like growth factor 1 (IGF-1)/IGF-1 binding protein (IGFBP-3) molar ratio than those in the low-risk group (corrected height standard deviation score 0.22±0.93 vs. -0.04±0.84, P<0.05; molar ratio 0.199±0.035 vs. 0.211+0.039, P<0.05). Children with DAAB tended to be taller and to have a higher body mass index than those with no DAAB. Our results suggest that the accelerator hypothesis explaining the increasing incidence of T1D may not solely be dependent on environmental factors, but could be partially genetically determined.

Higher circulating EGF levels associate with a decreased risk of IgE sensitization in young children.

BACKGROUND: Decreased exposure to microbial agents in industrialized countries and urban living areas is considered as a risk factor of developing immune-mediated diseases, such as allergies and asthma. Epithelial surfaces in the gastrointestinal and respiratory tracts and in the skin constitute the primary areas in contact with the environmental microbial load. METHODS: We analyzed the levels of 30 cytokines and growth factors in serum or plasma as markers of the immune maturation in the participants in the DIABIMMUNE study from Russian Karelia (n = 60), Estonia (n = 83) and Finland (n = 89), three neighboring countries with remarkable differences in the incidences of allergies, asthma and autoimmune diseases. RESULTS: We observed an upregulation of T helper cell signature cytokines during the first 12 months of life, reflecting natural development of adaptive immune responses. During the first years of life, circulating concentrations of epidermal growth factor (EGF) were significantly higher, especially in Russian children compared with Finnish children. The children who developed IgE sensitization showed lower levels of EGF than those without such responses. CONCLUSION: Our results suggest that low circulating EGF levels associate with the risk of allergies possibly via the effects on the epithelial integrity and mucosal homeostasis.

The 2021 European Training Requirements in Paediatric Endocrinology and Diabetes.

The aims of the 2021 European Training Requirements (ETR) in Paediatric Endocrinology and Diabetes (PED) are to (1) provide standards to harmonize training programmes in PED between different European countries, (2) establish clearly defined standards of knowledge and skills required to practice PED at the tertiary care level, (3) foster the development of a network of competent tertiary care centres for PED in Europe and globally, and (4) improve the quality of care for children and adolescents requiring PED services. This ETR in PED specifies the requirements for training institutions, trainers, and trainees. It also provides the detailed syllabus/core content that trainees are expected to achieve in order to become competent independent clinicians in PED. References to consensus guidelines produced and/or endorsed by ESPE are included. The target users are trainees in PED, trainers, and all involved with quality assurance and accreditation. The process to develop and approve this 2021 ETR has been rigorous and involved trainees and consultants in paediatric and adult Endocrinology, ESPE (Syllabus Task Force, Education and Training Committee, Council), European Academy of Paediatrics (Tertiary Care Council, Assembly), European Board of Paediatrics, and Union of European Medical Specialists. Implementing the ETR will complement professional regulatory requirements for postgraduate training in PED in different countries and allow harmonizing standards across Europe. ETR is publicly available at www.eurospe.org/education/education-training-syllabus and at https://www.uems.eu/__data/assets/pdf_file/0007/133990/UEMS-2021.17-European-Training-Requirement-in-Paediatric-Endocrinology.pdf.

Thyroid peroxidase antibodies are common in children with HLA-conferred susceptibility to type 1 diabetes, but are weakly associated with thyroid function.

Background The need for screening for autoimmune thyroid disease in children who have HLA-conferred susceptibility to type 1 diabetes (T1D), but have not yet been diagnosed with T1D, has not been thoroughly studied. The aim of this study was to describe the prevalence of positive thyroid peroxidase antibodies and its effect on thyroid function in children with genetic susceptibility to T1D as well as to describe the association between thyroid autoimmunity and HLA-DQ genotypes. Methods Cross-sectional study in 223 children (112 boys) aged 7.4-10.5 years with HLA-conferred susceptibility to T1D. TPOAb were measured in all children; thyroglobulin antibodies (TGAb) and thyroid function in TPOAb positive subjects. Results Girls had a significantly higher median TPOAb concentration than boys (12 vs 11 kU/L; p=0.001). Positive TPOAb occurred in 13.9% and positive TGAb in 4% of subjects. Only two children had mild changes in thyroid function. There was no association between HLA risk groups and the prevalence of TPOAb. Conclusions TPOAb are common in children with HLA-conferred susceptibility to T1D, yet are weakly associated with thyroid function, suggesting limited value of thyroid screening in this cohort.

Contrasting microbiotas between Finnish and Estonian infants: Exposure to Acinetobacter may contribute to the allergy gap.

BACKGROUND: Allergic diseases are more common in Finland than in Estonia, which-according to the biodiversity hypothesis-could relate to differences in early microbial exposures. METHODS: We aimed at defining possible microbial perturbations preceding early atopic sensitization. Stool, nasal and skin samples of 6-month-old DIABIMMUNE study participants with HLA susceptibility to type 1 diabetes were collected. We compared microbiotas of sensitized (determined by specific IgE results at 18 months of age) and unsensitized Estonian and Finnish children. RESULTS: Sensitization was differentially targeted between populations, as egg-specific and birch pollen-specific IgE was more common in Finland. Microbial diversity and community composition also differed; the genus Acinetobacter was more abundant in Estonian skin and nasal samples. Particularly, the strain-level profile of Acinetobacter lwoffii was more diverse in Estonian samples. Early microbiota was not generally associated with later sensitization. Microbial composition tended to differ between children with or without IgE-related sensitization, but only in Finland. While land-use pattern (ie green areas vs. urban landscapes around the children's homes) was not associated with microbiota as a whole, it associated with the composition of the genus Acinetobacter. Breastfeeding affected gut microbial composition and seemed to protect from sensitization. CONCLUSIONS: In accordance with the biodiversity hypothesis, our results support disparate early exposure to environmental microbes between Finnish and Estonian children and suggest a significant role of the genus Acinetobacter in the allergy gap between the two populations. The significance of the observed differences for later allergic sensitization remains open.

Immunomodulatory Effects of Rhinovirus and Enterovirus Infections During the First Year of Life.

Early childhood infections have been implicated in the development of immune-mediated diseases, such as allergies, asthma, and type 1 diabetes. We set out to investigate the immunomodulatory effects of early viral infections experienced before the age of one year on the peripheral regulatory T cell population (Treg) and circulating cytokines in a birth-cohort study of Estonian and Finnish infants. We show here a temporal association of virus infection with the expression of FOXP3 in regulatory T cells. Infants with rhinovirus infection during the preceding 30 days had a higher FOXP3 expression in Treg cells and decreased levels of several cytokines related to Th1 and Th2 responses in comparison to the children without infections. In contrast, FOXP3 expression was significantly decreased in highly activated (CD4+CD127-/loCD25+FOXP3high) regulatory T cells (TregFOXP3high) in the infants who had enterovirus infection during the preceding 30 or 60 days. After enterovirus infections, the cytokine profile showed an upregulation of Th1- and Th17-related cytokines and a decreased activation of CCL22, which is a chemokine derived from dendritic cells and associated with Th2 deviation. Our results reveal that immunoregulatory mechanisms are up-regulated after rhinovirus infections, while enterovirus infections are associated with activation of proinflammatory pathways and decreased immune regulation.

Maturation of Gut Microbiota and Circulating Regulatory T Cells and Development of IgE Sensitization in Early Life.

Recent studies suggest that the cross-talk between the gut microbiota and human immune system during the first year of life is an important regulator of the later development of atopic diseases. We explored the changes in the gut microbiota, blood regulatory T cells, and atopic sensitization in a birth-cohort of Estonian and Finnish children followed from 3 to 36 months of age. We describe here an infant Treg phenotype characterized by high Treg frequency, the maturation of Treg population characterized by a decrease in their frequency accompanied with an increase in the highly activated Treg cells. These changes in Treg population associated first with the relative abundance of Bifidobacterium longum followed by increasing colonization with butyrate producing bacteria. High bifidobacterial abundance in the neonatal microbiota appeared to be protective, while colonization with Bacteroides and E. coli was associated with later risk of allergy. Estonian children with lower risk of IgE mediated allergic diseases than Finnish children showed an earlier maturation of the gut microbiota, detected as earlier switch to an increasing abundance of butyrate-producing bacteria, combined with an earlier maturation of Treg cell phenotype and total IgE production. The children with established allergic diseases by age 3 showed a decreased abundance of butyrate producing Faecalibacterium. These results suggest that as well as the maintenance of a bifidobacterial dominated gut microbiota is important during the first weeks of life, the overtake by butyrate producing bacteria seems to be a beneficial shift, which should not be postponed.

Early Detection of Peripheral Blood Cell Signature in Children Developing ß-Cell Autoimmunity at a Young Age.

The appearance of type 1 diabetes (T1D)-associated autoantibodies is the first and only measurable parameter to predict progression toward T1D in genetically susceptible individuals. However, autoantibodies indicate an active autoimmune reaction, wherein the immune tolerance is already broken. Therefore, there is a clear and urgent need for new biomarkers that predict the onset of the autoimmune reaction preceding autoantibody positivity or reflect progressive ß-cell destruction. Here we report the mRNA sequencing-based analysis of 306 samples including fractionated samples of CD4+ and CD8+ T cells as well as CD4-CD8- cell fractions and unfractionated peripheral blood mononuclear cell samples longitudinally collected from seven children who developed ß-cell autoimmunity (case subjects) at a young age and matched control subjects. We identified transcripts, including interleukin 32 (IL32), that were upregulated before T1D-associated autoantibodies appeared. Single-cell RNA sequencing studies revealed that high IL32 in case samples was contributed mainly by activated T cells and NK cells. Further, we showed that IL32 expression can be induced by a virus and cytokines in pancreatic islets and ß-cells, respectively. The results provide a basis for early detection of aberrations in the immune system function before T1D and suggest a potential role for IL32 in the pathogenesis of T1D.

A retrospective analysis of the prevalence of imprinting disorders in Estonia from 1998 to 2016.

Imprinting disorders (ImpDis) represent a small group of rare congenital diseases primarily affecting growth, development, and the hormonal and metabolic systems. The aim of present study was to identify the prevalence of the ImpDis in Estonia, to describe trends in the live birth prevalence of these disorders between 1998 and 2016, and to compare the results with previously published data. We retrospectively reviewed the records of all Estonian patients since 1998 with both molecularly and clinically diagnosed ImpDis. A prospective study was also conducted, in which all patients with clinical suspicion for an ImpDis were molecularly analyzed. Eighty-seven individuals with ImpDis were identified. Twenty-seven (31%) of them had Prader-Willi syndrome (PWS), 15 (17%) had Angelman syndrome (AS), 15 (17%) had Silver-Russell syndrome (SRS), 12 (14%) had Beckwith-Wiedemann syndrome (BWS), 10 (11%) had pseudo- or pseudopseudohypoparathyroidism, four had central precocious puberty, two had Temple syndrome, one had transient neonatal diabetes mellitus, and one had myoclonus-dystonia syndrome. One third of SRS and BWS cases fulfilled the diagnostic criteria for these disorders, but tested negative for genetic abnormalities. Seventy-six individuals were alive as of January 1, 2018, indicating the total prevalence of ImpDis in Estonia is 5.8/100,000 (95% CI 4.6/100,000-7.2/100,000). The minimum live birth prevalence of all ImpDis in Estonia in 2004-2016 was 1/3,462, PWS 1/13,599, AS 1/27,198, BWS 1/21,154, SRS 1/15,866, and PHP/PPHP 1/27,198. Our results are only partially consistent with previously published data. The worldwide prevalence of SRS and GNAS-gene-related ImpDis is likely underestimated and may be at least three times higher than expected.

Early childhood infections and the use of antibiotics and antipyretic-analgesics in Finland, Estonia and Russian Karelia.

AIM: Infections in early childhood are common reasons to seek medical attention. This study compares the prevalence of infections, and the use of antibiotics and antipyretic-analgesics, in children from Finland, Estonia and Russian Karelia. METHODS: Children with a genetically increased risk for type 1 diabetes (N = 797) were observed from birth up to 3 years of age. Illnesses and medications were reported by parents continuously. All reported infections, antibiotics and antipyretic-analgesics were compared between Finland and Estonia, and to a lesser extent with Russian Karelia, due to poor study compliance. RESULTS: Compared with Estonians, Finns reported more infections during the first and second years of life. During the follow-up, Finnish children had 10 infections while Estonians only had 8 (p < 0.001). Finns also used more antibiotics and antipyretic-analgesics in each year during the follow-up. Russian Karelians reported the lowest frequency of infections and the most infrequent use of antibiotics and antipyretic-analgesics in the first two years of life. CONCLUSION: Infections and the use of antibiotics and antipyretic-analgesics in early childhood were most frequent in Finland, where socio-economic conditions are the most developed and microbial encounters are sparse. This may reflect on the hygiene hypothesis, a less effective immune system that allows normally harmless microbes to attack and cause clinical infections.

Rhinoviruses in infancy and risk of immunoglobulin E sensitization.

Previous data about the role of viruses in the development of allergic immunoglobulin E (IgE) sensitization are contradictory. The aim of this study was to determine the possible associations between exposure to different viruses (rhinovirus, enterovirus, norovirus, and parechovirus) during the first year of life and IgE sensitization. Viruses were analyzed from stool samples collected monthly from infants participating in a prospective birth cohort study. From that study, 244 IgE sensitized case children and 244 nonsensitized control children were identified based on their allergen-specific IgE antibody levels at the age of 6, 18, and 36 months. Stool samples (n = 4576) from the case and control children were screened for the presence of rhinovirus, enterovirus, norovirus, and parechovirus RNA by reverse transcription quantitative polymerase chain reaction. The study showed that rhinovirus was the most prevalent virus detected, present in 921 (20%) samples. None of the viruses were associated with IgE sensitization in the full cohort but after stratifying by sex, the number of rhinovirus positive samples was inversely associated with IgE sensitization in boys (odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.69-0.94; P = 0.006). There was also a temporal relation between rhinoviruses and IgE sensitization, as rhinovirus exposure during the first 6 months of life was associated with a reduced risk of subsequent IgE sensitization in boys (OR: 0.76; 95% CI: 0.6-0.94; P = 0.016). In conclusion, early exposure to rhinoviruses was inversely associated with IgE sensitization but this protective association was restricted to boys.

Early-life exposure to common virus infections did not differ between coeliac disease patients and controls.

AIM: Our aim was to compare the presence of various common viruses (rhinovirus, enterovirus, adenovirus, Epstein-Barr virus, cytomegalovirus, norovirus, parechovirus) in stool and nasal swab samples as well as virus-specific antibodies in serum samples between children who developed coeliac disease and controls. METHODS: A case-control study was established based on the DIABIMMUNE Study cohorts. During the study, eight Estonian children and 21 Finnish children aged 1.5 years to five years developed coeliac disease and each was matched with a disease-free control. Nasal swabs and stool samples were taken at the age of three to six months and the serum samples at the time of diagnosis. RESULTS: Rhinovirus ribonucleic acid was detected in the nasal swabs from five coeliac disease children, but none of the control children (p = 0.05). There were no statistically significant differences in the level of viral antibodies between cases and controls. Enterovirus immunoglobulin G class antibodies were found more frequently in the Estonian than in the Finnish children (63% versus 23%, p = 0.02). CONCLUSION: This study did not find any marked overall differences in laboratory-confirmed common viral infections between the children who developed coeliac disease and the controls. However, rhinovirus infections were detected slightly more often in those patients who developed coeliac disease.

Development of atopic sensitization in Finnish and Estonian children: A latent class analysis in a multicenter cohort.

BACKGROUND: The prevalence of atopy is associated with a Western lifestyle, as shown by studies comparing neighboring regions with different socioeconomic backgrounds. Atopy might reflect various conditions differing in their susceptibility to environmental factors. OBJECTIVE: We sought to define phenotypes of atopic sensitization in early childhood and examine their association with allergic diseases and hereditary background in Finland and Estonia. METHODS: The analysis included 1603 Finnish and 1657 Estonian children from the DIABIMMUNE multicenter young children cohort. Specific IgE levels were measured at age 3, 4, and 5 years, respectively, and categorized into 3 CAP classes. Latent class analysis was performed with the statistical software package poLCA in R software. RESULTS: Both populations differed in terms of socioeconomic status and environmental determinants, such as pet ownership, farm-related exposure, time spent playing outdoors, and prevalence of allergic diseases (all P < .001). Nevertheless, we found similar latent classes in both populations: an unsensitized class, a food class, 2 inhalant classes differentiating between seasonal and perennial aeroallergens, and a severe atopy class. The latter was characterized by high total and specific IgE levels and strongly associated with wheeze (odds ratio [OR], 5.64 [95% CI, 3.07-10.52] and 4.56 [95% CI, 2.35-8.52]), allergic rhinitis (OR, 22.4 [95% CI, 11.67-44.54] and 13.97 [95% CI, 7.33-26.4]), and atopic eczema (OR, 9.39 [95% CI, 4.9-19.3] and 9.5 [95% CI, 5.2-17.5] for Finland and Estonia, respectively). Environmental differences were reflected in the larger seasonal inhalant atopy class in Finland, although composition of classes was comparable between countries. CONCLUSION: Despite profound differences in environmental exposures, there might exist genuine patterns of atopic sensitization. The distribution of these patterns might determine the contribution of atopic sensitization to disease onset.

Characterization and non-parametric modeling of the developing serum proteome during infancy and early childhood.

Children develop rapidly during the first years of life, and understanding the sources and associated levels of variation in the serum proteome is important when using serum proteins as markers for childhood diseases. The aim of this study was to establish a reference model for the evolution of a healthy serum proteome during early childhood. Label-free quantitative proteomics analyses were performed for 103 longitudinal serum samples collected from 15 children at birth and between the ages of 3-36 months. A flexible Gaussian process-based probabilistic modelling framework was developed to evaluate the effects of different variables, including age, living environment and individual variation, on the longitudinal expression profiles of 266 reliably identified and quantified serum proteins. Age was the most dominant factor influencing approximately half of the studied proteins, and the most prominent age-associated changes were observed already during the first year of life. High inter-individual variability was also observed for multiple proteins. These data provide important details on the maturing serum proteome during early life, and evaluate how patterns detected in cord blood are conserved in the first years of life. Additionally, our novel modelling approach provides a statistical framework to detect associations between covariates and non-linear time series data.