Celiac disease revealed in 3% of Swedish 12-year-olds born during an epidemic

Decreasing incidence of celiac disease in Southern Sweden

BACKGROUND

The incidence of celiac disease (CD) has increased rapidly in the late 20th and early 21st centuries, but there are recent reports of rates levelling off in countries with a high prevalence. The aim of this study was to investigate current trends in CD in southern Sweden.

PATIENTS AND METHODS

Children and adults diagnosed with CD by biopsy or serology in the region of Skåne, southern Sweden, from 2010-2022 were included. The home address was identified through registers to analyze temporal and geographical trends.

RESULTS

A total of 3218 CD-patients were identified (52.2% children), the vast majority detected in clinical care but a few children by screening studies. The age-standardized incidence rate was 18.6 cases/105. The incidence decreased at a rate of -0.75 cases/105 (95% CI -1.14 to -0.35, p 0.002). The incidence among girls under 18 years almost halved throughout the study period, decreasing by -2.94 cases/105 (95% CI -4.59 to -1.29, p 0.002), while there only were small changes among men. The most common age of onset was 3-9 years. CD incidence varied by place of living and was more common in small towns than urban or rural areas.

CONCLUSIONS

The incidence of CD in southern Sweden is decreasing, primarily in children and women who traditionally have had the highest risk of CD. CD was diagnosed most frequently in children 3-9 years old. There were regional variations in incidence. CD was most common in small towns, pointing to the importance of environmental factors in CD etiology.

Laboratory Testing for Celiac Disease: Clinical and Methodological Considerations

BACKGROUND

Celiac disease (CeD) has an estimated prevalence of 1%-3%. The classical clinical presentation is malabsorption, but now patients may present with more subtle symptoms such as constipation, osteoporosis, or iron deficiency anemia. Children may also present with poor growth.CeD has a strong genetic component, and high-risk groups include first-degree relatives with CeD, patients with co-existing autoimmune diseases, and patients with chromosomal aberrations.

CONTENT

Diagnostic tests for CeD include duodenal histology, serology, and genetic testing. Duodenal histology has traditionally been the gold standard of diagnosis. However, serological tests, especially IgA tissue transglutaminase antibodies (TTG-IgA), are widely used and diagnostic algorithms are based primarily on TTG-IgA as a starting point. Human leukocyte antigen typing may also be incorporated to determine genetic risk for CeD. Guidelines for children endorse biopsy avoidance provided high levels of TTG-IgA, with diagnostic accuracy being comparable to duodenal biopsy. Confirmation may be achieved by identifying IgA endomysial antibodies in a separate blood sample. Subjects with low positive TTG-IgA levels and subjects with IgA deficiency need a biopsy to establish a diagnosis of CeD. The clinical follow-up of CeD usually includes a repeat TTG-IgA examination. In adults, healing may be delayed or incomplete, and a rare consequence of refractory celiac disease is transformation to enteric T-cell lymphoma.

SUMMARY

Laboratory testing, in particular TTG-IgA, plays a central role in the diagnosis and has an accuracy comparable to histology. Diagnostic algorithms utilizing laboratory testing are critical for the development of novel strategies to improve diagnosis.

Home capillary sampling and screening for type 1 diabetes, celiac disease, and autoimmune thyroid disease in a Swedish general pediatric population: the TRIAD study

Objective

To screen a general pediatric population for type 1 diabetes (T1D), celiac disease (CD), and autoimmune thyroid disease (AITD) after home capillary sampling.

Methods

Swedish schoolchildren between 6-9 years and 13-16 years of age were invited to screening by taking a capillary sample at home. Samples were returned by mail and assessed for autoantibodies associated with T1D, CD, and AITD. Persistently autoantibody-positive children were referred for clinical follow-up.

Results

Of 19,593 invited, 3,527 (18.0%) consented to participate and 2,315/3,527 (65.6%) returned a blood sample of sufficient volume. Hemolysis occurred in 830/2,301 (36.1%) samples. After exclusion of 42 children with previously known T1D, CD, or AITD, and two autoantibody-positive children who declined a confirmatory sample, 2,271/19,593 (11.6%) were included. 211/2,271 (9.3%) had persistent autoantibodies: 60/2,271 (2.6%) with T1D autoantibodies, 61/2,271 (2.7%) with CD autoantibodies, and 99/2,271 (4.4%) with AITD autoantibodies; 9/2,271 (0.4%) were autoantibody positive for ≥1 disease. After clinical follow-up, 3/2,271 (0.1%) were diagnosed with T1D, 26/2,271 (1.1%) with CD, and 6/2,271 (0.3%) with AITD. Children with a first-degree relative (FDR) with T1D, CD, and/or AITD, had higher occurrence of autoantibodies compared to children without an FDR (63/344, 18.3%, vs. 148/1,810, 8.2%) (p < 0.0001, OR 2.52, 95% CI 1.83-3.47), and higher occurrence of screening-detected diagnosis (14/344, 4.1%, vs. 21/1,810, 1.2%) (p < 0.0001, OR 3.61, 95% CI 1.82-7.18). Half of these children screened positive for another disease than the FDR.

Conclusion

Screening for T1D, CD, and AITD by home capillary sampling in a Swedish general pediatric population detected autoimmunity in 9.3% and undiagnosed disease in 1.5%.

Measured levels of positive transglutaminase 2 antibodies are not associated with presentation or incidental endoscopic findings at celiac disease diagnosis

OBJECTIVES

It has been suggested that celiac disease could be diagnosed non-invasively in adults with transglutaminase antibody (TGA) levels >10x upper limit of normal (ULN). It is, however, unclear if high values signify more advanced disease and higher risk of co-morbidities. We investigated the association between the TGA levels, clinical characteristics and non-celiac endoscopic findings.

METHODS

Medical data on 450 celiac disease patients at diagnosis were collected. They were further divided into those with high positive (>10x ULN, n = 164), moderately positive (1-10x ULN, n = 219), and negative (n = 67) TGA.

RESULTS

Median age of patients was 50 years and 60% were women. Patients with negative TGA were older (median age 58 vs. 51 vs. 46 years respectively, p = 0.002) and had more often weight loss (27% vs. 10% vs. 9%, p < 0.001) and abdominal pain or dyspepsia (40% vs 27% vs. 22%, p = 0.017) than did those with moderately positive/high TGA. The groups did not differ in sex, BMI, or other symptoms. Major endoscopic findings included one esophageal adenocarcinoma presenting with dysphagia, six esophagitis, three gastric ulcers, and 39 H. Pylori or other active gastritis. High, moderately positive or negative TGA levels were not associated with these findings in crude or age-adjusted analyses.

CONCLUSIONS

Presentation was similar in patients with moderate or high levels of TGA, whereas patients with negative TGA were different. The level of TGA was not associated with incidental endoscopic findings and the only malignancy presented with an alarm symptom atypical to celiac disease.

Could Celiac Disease and Overweight/Obesity Coexist in School-Aged Children and Adolescents? A Systematic Review

Background: Celiac disease (CD) is a multifactorial, immune-mediated enteropathic disorder that may occur at any age with heterogeneous clinical presentation. In the last years, unusual manifestations have become very frequent, and currently, it is not so uncommon to diagnose CD in subjects with overweight or obesity, especially in adults; however, little is known in the pediatric population. This systematic review aims to evaluate the literature regarding the association between CD and overweight/obesity in school-age children. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. An electronic database search of articles published in the last 20 years in English was carried out in Web of Sciences, PubMed, and Medline. The quality of the included studies was assessed by using the STrengthening the Reporting of OBservational studies in Epidemiology statement. Results: Of the 1396 articles identified, 9 articles, investigating overweight/obesity in children/adolescents affected by CD or screening CD in children/adolescents with overweight/obesity, met the inclusion criteria. Overall, the results showed that the prevalence of overweight or obesity in school-age children (6-17 years) affected by CD ranged between 3.5% and 20%, highlighting that the coexistence of CD with overweight/obesity in children is not uncommon as previously thought. Conclusion: Although CD has been historically correlated with being underweight due to malabsorption, it should be evaluated also in children with overweight and obesity, especially those who have a familiar predisposition to other autoimmune diseases and/or manifest unusual symptoms of CD.

Cumulative incidence of type 1 diabetes in two cohorts of children with different national gluten recommendations in infancy

AIMS

Between 1985 and 1996, Sweden experienced an "epidemic" of celiac disease with a fourfold increase in incidence in young children. Timing and amount of gluten introduced during infancy have been thought to explain this "epidemic". We aimed to study whether the cumulative incidence of type 1 diabetes differs between children born during the "epidemic" compared to children born after.

METHODS

This is a national register study in Sweden comparing the cumulative incidence of type 1 diabetes in two birth cohorts of 240 844 children 0-17 years old born 1992-1993, during the "epidemic", and 179 530 children born 1997-1998, after the "epidemic". Children diagnosed with type 1 diabetes were identified using three national registers.

RESULTS

The cumulative incidence of type 1 diabetes by the age of 17 was statistically significantly higher in those born after the "epidemic" 0.77% than in those born during the "epidemic" 0.68% (p < 0.001).

CONCLUSION

The incidence of type 1 diabetes is higher in those born after the epidemic compared to those born during the epidemic, which does not support the hypothesis that gluten introduction increases the incidence of T1D. Changes in gluten introduction did not halt the increased incidence of type 1 diabetes in Sweden.

A Population-Based Cross-Sectional Study of Paediatric Coeliac Disease in Catalonia Showed a Downward Trend in Prevalence Compared to the Previous Decade

(1) Background: Previous studies showed an increased prevalence and incidence of coeliac disease (CD) over time. The objective is to ascertain whether the CD prevalence in Catalonia (a region of Southern Europe) among children aged 1-5 is as high as previously found in 2004-2009; (2) Methods: From 2013 to 2019, 3659 subjects aged 1-5 years were recruited following the previously used methodology. Factors with a potential impact on CD prevalence were investigated; (3) Results: In 2013-2019, 43/3659 subjects had positive serology, giving a standardised seroprevalence of 12.55/1000 (95% CI: 8.92; 17.40), compared to 23.62 (13.21; 39.40) in 2004-2007. The biopsy-proven crude prevalence was 7.92/1000 (95% CI: 5.50; 11.30), and the crude prevalence based on ESPGHAN criteria was 8.74/1000 (95% CI: 6.20-12.30). In contrast to 2004-2009, we did not find differences in the seroprevalence rates between 1 and 2 years vs. 3 and 4 years of age (age percentage of change -7.0 (-29.5; 22.8) vs. -45.3 (-67.5; -8.0)). Rotavirus vaccination was the most remarkable potential protective factor (48% vs. 9% in 2004-2009; p < 0.0001), but not the time of gluten introduction. (4) Conclusion: The present study did not confirm a worldwide CD prevalence increase and emphasizes the need to perform prevalence studies over time using the same methodology in the same geographical areas.

Relationship between gluten availability and celiac disease prevalence: A geo-epidemiologic systematic review

Celiac disease is a global disease requiring genetic susceptibility and gluten exposure to trigger immune-mediated enteropathy. The effect of the degree of gluten-containing grain availability on celiac disease prevalence is unknown. Our objective was to compare country-based gluten availability to celiac prevalence using a systematic literature review. We searched MEDLINE, Embase, Cochrane, and Scopus until May 2021. We included population-based serum screening with confirmatory testing (second serological study or small intestine biopsy) and excluded specific, high-risk, or referral populations. We determined country-specific gluten availability using the United Nations food balance for wheat, barley, and rye. Human leukocyte antigen (HLA) frequencies were obtained from allelefrequencies.net. The primary outcome was association between gluten-containing grain availability and celiac disease prevalence. Generalized linear mixed models method with Poisson's link was used for analysis. We identified 5641 articles and included 120 studies on 427 146 subjects from 41 countries. Celiac disease prevalence was 0-3.1%, median 0.75% (interquartile range 0.35, 1.22). Median wheat supply was 246 g/capita/day (interquartile range 214.8, 360.7). The risk ratio (RR) for wheat availability on celiac disease was 1.002 (95% confidence interval [CI]: 1.0001, 1.004, P = 0.036). A protective association was seen with barley, RR 0.973 (95% CI: 0.956, 0.99, P = 0.003), and rye, RR 0.989 (95% CI: 0.982, 0.997, P = 0.006). The RR for gross domestic product on celiac disease prevalence was 1.009 (95% CI: 1.005, 1.014, P < 0.001). The RR for HLA-DQ2 was 0.982 (95% CI: 0.979, 0.986, P < 0.001), and that for HLA-DQ8 was 0.957 (95% CI: 0.950, 0.964, P < 0.001). In this geo-epidemiologic study, gluten-containing grain availability showed mixed associations with celiac disease prevalence.

The prevalence of having coeliac disease in children with type 1 diabetes was not significantly higher during the Swedish coeliac epidemic

AIM

From 1986 to 1996, there was a four-fold increase in coeliac disease among young Swedish children, known as the Swedish coeliac epidemic. Children with type 1 diabetes have an increased risk of developing coeliac disease. We studied whether the prevalence of coeliac disease differed in children with type 1 diabetes born during and after this epidemic.

METHODS

We compared national birth cohorts of 240 844 children born in 1992-1993 during the coeliac disease epidemic and 179 530 children born in 1997-1998 after the epidemic. Children diagnosed with both type 1 diabetes and coeliac disease were identified by merging information from five national registers.

RESULTS

There was no statistically significant difference in the prevalence of coeliac disease among children with type 1 diabetes between the two cohorts: 176/1642 (10.7%, 95% confidence interval 9.2%-12.2%) in the cohort born during the coeliac disease epidemic versus 161/1380 (11.7%, 95% confidence interval 10.0%-13.5%) in the post-epidemic cohort.

CONCLUSION

The prevalence of having both coeliac disease and type 1 diabetes was not significantly higher in children born during, than after, the Swedish coeliac epidemic. This may support a stronger genetic disposition in children who develop both conditions.

Coronavirus disease 2019 and gastrointestinal disorders in children

During the past 3 years, the coronavirus disease 2019 (COVID-19) pandemic has had a great impact on people all over the world. However, it has become evident that disease manifestations and severity differ across age groups. Most children have a milder disease course than adults but possibly more pronounced gastrointestinal (GI) symptoms. Given the child's developing immune system, the impact of COVID-19 on disease development may differ compared to adults. This study reviews the potential bi-directional relationship between COVID-19 and GI diseases in children, focusing on common pediatric conditions such as functional GI disorders (FGID), celiac disease (CeD), and inflammatory bowel disease (IBD). Children with GI diseases, in general, and CeD and IBD, in particular, do not seem to have an increased risk of severe COVID-19, including risks of hospitalization, critical care need, and death. While infections are considered candidate environmental factors in both CeD and IBD pathogenesis, and specific infectious agents are known triggers for FGID, there is still not sufficient evidence to implicate COVID-19 in the development of either of these diseases. However, given the scarcity of data and the possible latency period between environmental triggers and disease development, future investigations in this field are warranted.

Intervention strategies in early childhood to prevent celiac disease-a mini-review

A higher intake of gluten during childhood is associated with increased risk of celiac disease, and the incidence of celiac disease peaks shortly after the time point when associations with higher gluten intake during the second and third year of life occur. Additional environmental factors are most likely necessary for celiac disease to develop. It is hypothesized that gastrointestinal infections increase gut permeability and exposure to gluten. Alternatively, infections may lead to gut dysbiosis and chronic inflammation, with leakage of self-antigens that mimic gluten peptides that leads to an autoimmune-like response. Different gluten interventions to prevent celiac disease have been proposed. Early clinical studies suggested an optimal time point introducing gluten between 4 and 6 months of age while the infant is being breastfed. However, later clinical trials on reduced gluten intake given to infants have shown no protection from celiac disease if gluten introduction was delayed or if gluten was introduced in small amounts during the child's first year of life. Still, more randomized clinical trials (RCTs) are warranted to answer the question if a reduced amount of gluten, not only at the time of introduction during infancy but also in a longer time frame, will prevent children at genetic risk from having lifelong celiac disease. It needs to be clarified whether dietary interventions are effective strategies to be proposed as future prevention of celiac disease in the general population. The present mini-review provides an overview of ongoing or completed RCTs that have focused on interventions during early childhood with the aim of preventing celiac disease.

Point-of-Care Screening for Coeliac Disease in Schoolchildren Reveals Higher Disease Prevalence in Croatia

Coeliac disease (CD) is an immune-mediated inflammatory disease triggered by dietary gluten and related proteins in genetically predisposed individuals. Point-of-care (POC) methods are non-invasive and easily performed tests, which could help to reduce the diagnostic delay of CD. The aim of our study was to determine the prevalence of CD using rapid POC test in first-grade schoolchildren in Zagreb, Croatia. A rapid qualitative immunoassay POC test designed for detection of immunoglobulin (Ig) A and IgG deamidated gliadin antibodies (DGP), as well as total IgA (to identify IgA deficient patients) in whole blood, was used to test healthy children on gluten containing diet. Out of 1404 tested children (51% female), 85 (6.05%) had a positive rapid POC test result and were referred to paediatric gastroenterologist. Finally, 7 children were diagnosed with CD (0.5%). There was no significant difference in children with CD and children with positive POC but negative serology in sex, BMI, or symptoms. However, children diagnosed with CD complained of abdominal pain significantly more often. The prevalence of CD in first-grade schoolchildren was 1:200 (0.5%), higher than in previous studies performed in Croatia. The results imply the possible benefit of IgA and IgG DGP-based POC tests in population screening.

Celiac disease and upper secondary school achievement in Sweden A retrospective cohort study

BACKGROUND

Both undiagnosed celiac disease and some chronic childhood diseases are associated with lower academic achievement. However, there is little knowledge of achievements in those diagnosed with celiac disease. Our aim was to investigate school achievements in upper secondary school among Swedish adolescents with celiac disease.

METHODS

We performed a retrospective cohort study using register data. We analyzed choice of upper secondary school program, completion of upper secondary school including achievements of basic eligibility for college/university, and final grade in individuals with celiac disease diagnosed before 15 years of age, born 1991-97. We compared with the Swedish population of the same birth years. Analyses were adjusted for sex, year of birth, living region at 17 years of age, and parental education as well as income.

RESULTS

The cohort included 734 074 individuals, whereof 3 257 (62% females) with celiac disease. There was no significant difference in choice of upper secondary school program. No significant difference was found in completion or achieving basic eligibility for college/university in adjusted analyses. The mean final grade in the celiac disease group was 13.34 (standard deviation 4.85) compared to 12.78 (standard deviation 5.01) in the reference population (p < 0.001), out of a maximum of 20. The effect of celiac disease on final grade remained in adjusted analyses (p = 0.012).

CONCLUSIONS

We found that diagnosed celiac disease does not negatively affect school achievements in upper secondary school. This finding suggests the diagnosis, treatment and follow-up programs of celiac disease could reverse potential deleterious academic processes.

Celiac disease screening at a pediatric outpatient clinic: a feasibility study

OBJECTIVES

Celiac disease (CD) is a common yet largely underdiagnosed disease. This study aimed to test the feasibility of incorporating a non-targeted CD screening in a pediatric outpatient setting and evaluate its short-term impact on children with serological evidence of disease.

METHODS

Over five months, 500 children (aged 2-17 years) attending a general pediatric outpatient clinic in Gothenburg, Sweden, were enrolled and surveyed for current symptoms, quality of life, and background characteristics; 481 children were screened for tissue-transglutaminase antibodies (tTGA); repeated tTGA-positivity was defined as CD autoimmunity (CDA). Children with CDA were investigated for CD and for one year monitored for changes in symptoms, and quality of life.

RESULTS

Eleven of 481 (2.3%) screened children had CDA. Children with CDA were younger (median 3.8 years) than those without CDA (8.8 years). No other major between-group differences were reported in background characteristics, symptoms, or quality of life. The screening was well-accepted by the families/participants. During 1-year follow-up, 8 of 11 children with CDA were diagnosed with CD. Children with screening-detected CD reported no significant changes in symptoms and quality of life and the dietary adherence rate was good.

CONCLUSIONS

Non-targeted screening for CD was feasible in a general pediatric outpatient setting. While hampered by small sample size, our results are in line with previous screening studies indicating that symptoms do not differentiate CDA from non-CDA children. Also, among an overall minimal-symptomatic group of children, diagnosing CD and installation of treatment did not significantly change their well-being during 1-year follow-up.

Gut microbiome markers in subgroups of HLA class II genotyped infants signal future celiac disease in the general population: ABIS study

Although gut microbiome dysbiosis has been illustrated in celiac disease (CD), there are disagreements about what constitutes these microbial signatures and the timeline by which they precede diagnosis is largely unknown. The study of high-genetic-risk patients or those already with CD limits our knowledge of dysbiosis that may occur early in life in a generalized population. To explore early gut microbial imbalances correlated with future celiac disease (fCD), we analyzed the stool of 1478 infants aged one year, 26 of whom later acquired CD, with a mean age of diagnosis of 10.96 ± 5.6 years. With a novel iterative control-matching algorithm using the prospective general population cohort, All Babies In Southeast Sweden, we found nine core microbes with prevalence differences and seven differentially abundant bacteria between fCD infants and controls. The differences were validated using 100 separate, iterative permutations of matched controls, which suggests the bacterial signatures are significant in fCD even when accounting for the inherent variability in a general population. This work is the first to our knowledge to demonstrate that gut microbial differences in prevalence and abundance exist in infants aged one year up to 19 years before a diagnosis of CD in a general population.

Review article: Epidemiology of coeliac disease

Coeliac disease is an immune-mediated disease caused by ingestion of gluten in genetically susceptible individuals. Coeliac disease has been thought to affect mainly people of European origin but subsequently many studies revealed that it affects people living in North America, Oceania, South America, Asia as well as Africa. The global pooled seroprevalence and prevalence of biopsy-confirmed coeliac disease are 1.4% and 0.7% respectively. The pooled incidence rates in women and men are 17.4 (95% CI: 13.7-21.1) and 7.8 (95% CI: 6.3-9.2) per 100 000 person-years respectively. The systematic reviews, based on many population-based data, suggest that both the prevalence and the incidence of coeliac disease has increased over past three decades, which may be attributable not only to an increase in the detection rate (improvement in diagnostic tests, simplification of diagnostic criteria and increase in awareness about the disease) but also because of modernisation and globalisation related changes in the dietary practices including increase in the use of convenience food and dietary gluten. In addition to genetic factors, while there are many environmental risk factors, including age at the first introduction of gluten, breastfeeding, caesarean section, exposure to antibiotics and gut microbiome; the amount of gluten ingestion during early part of life, however, has been shown to increase the risk of coeliac disease, and this is relevant from the point of view of primary prevention. In this review, we have reviewed and summarised the literature, up till year 2021, related to the global and continent-wise epidemiology and risk factors associated with coeliac disease.

Two waves of coeliac disease incidence in Sweden: a nationwide population-based cohort study from 1990 to 2015

OBJECTIVES

To assess the incidence of biopsy-verified coeliac disease (CD) in Sweden and examine the incidence of duodenal/jejunal biopsies with normal mucosa over time as a proxy for CD awareness and investigation.

DESIGN

Nationwide population-based cohort study 1990-2015 based on biopsy reports indicating villous atrophy (VA) or normal mucosa in the duodenum/jejunum.

RESULTS

We identified 44 771 individuals (63% females) with a biopsy report specifying VA and 412 279 (62% females) with a biopsy report indicating normal mucosa (without a prior biopsy indicating VA). The median age at diagnosis of CD was 28 years. The mean age-standardised incidence rate during the study period was 19.0 per 100 000 person-years (95% CI 17.3 to 20.8). The incidence reached a peak in 1994 for both sexes and a second higher peak in 2002-2003 for females and in 2006 for males. The lifetime risk of developing CD was 1.8% (2.3% in females and 1.4% in males).Prior to 2015, there was a parallel rise in rates for biopsies showing normal duodenal/jejunal mucosa.

CONCLUSIONS

In Sweden, the incidence of CD increased until 2002-2003 in females and until 2006 in males. Since then, the incidence of CD has declined despite increasing duodenal/jejunal biopsies, suggesting that increased awareness and investigation are unlikely to elevate the incidence of the disease in Sweden. Across a lifetime, 1 in 44 females and 1 in 72 males are expected to be diagnosed with CD in Sweden, indicating a relatively high societal burden of disease.

Five-year follow-up of new cases after a coeliac disease mass screening

OBJECTIVE

We previously performed a population-based mass screening of coeliac disease in children aged 12 years in two birth cohorts resulting in 296 seropositive children, of whom 242 were diagnosed with coeliac disease after duodenal biopsies. In this follow-up study, we wanted to identify new cases in the screening population that tested negative-either converting from potential coeliac disease (seropositive but normal duodenal mucosa) or converting from seronegative at screening to diagnosed coeliac disease.

METHODS

All seropositive children were invited to a follow-up appointment 5 years after the screening with renewed serological testing and recommended endoscopic investigation if seropositive. Seronegative children in the screening study (n=12 353) were linked to the National Swedish Childhood Coeliac Disease Register to find cases diagnosed in healthcare during the same period.

RESULTS

In total, 230 (77%) came to the follow-up appointment, including 34 of 39 with potential coeliac disease. Of these, 11 (32%) had converted to coeliac disease. One new case was found in the National Swedish Childhood Coeliac Disease Register who received the diagnosis through routine screening in children with type 1 diabetes.

CONCLUSIONS

There is a high risk of conversion to coeliac disease among those with potential disease. However, a negative screening test was associated with a very low risk for a clinical diagnosis within a follow-up period of 5 years.

Real-world Follow-up Practice of Children With Coeliac Disease: A Cross-sectional Study From Western Sweden

Coeliac disease (CD) is one of the most common chronic diseases of childhood. Follow-up of CD aims to ensure dietary adherence and prevent disease complications, but there are few real-world data on how its management in children is conducted. This study aimed to survey the follow-up practice of pediatric CD in Western Sweden. Two web-based surveys were distributed to all 22 pediatric outpatient clinics rendering answers from 48 physicians and 12 dietitians. Overall, clinical practice was similar throughout the region and in line with national and international CD guidelines, including an annual to biannually follow-up frequency and dietary adherence assessment through unstructured interviewing and serology measurements. The study identified possible areas of improvement, such as implementing a formal transition process to adult care and the use of validated questionaries to assess dietary adherence. Additionally, a positive attitude towards electronic-health technologies (eHealth) as part of CD follow-up was identified.

High Prevalence of Celiac Disease Among Danish Adolescents: A Population-based Study

OBJECTIVES

The objective of this study was to establish an unselected cohort of Danish adolescents and estimate the prevalence of undiagnosed celiac disease (CeD).

METHODS

The Glutenfunen cohort participants were recruited from an unselected subsample of the Danish National Birth Cohort, defined as participants living in the Island of Funen, Denmark. We invited all 7431 eligible participants in the age range of 15 to 21 years to a clinical visit. CeD diagnosis was based on screening with IgA transglutaminase antibodies (TG2-IgA) and if positive, was followed by duodenal biopsies compatible with CeD (Marsh 2-3). We calculated the prevalence of CeD in the Glutenfunen cohort as the number of CeD cases diagnosed before and during the study divided by the number of participants in the Glutenfunen cohort.

RESULTS

We included 1266 participants in the Glutenfunen cohort (17%, 1266/7431). 1.1% (14 of 1266 participants) had CeD diagnosed before entering the cohort and based on the Danish National Patient Register, 0.2% of the nonparticipants (14 of 6165) had a diagnosis of CeD. In total, 2.6% (33 participants) had TG2 IgA above the upper limit of normal. Nineteen participants had duodenal biopsies compatible with CeD. The prevalence of CeD in the Glutenfunen cohort was 2.6% [(14 + 19)/1266].

CONCLUSIONS

Our study suggests that CeD is much more common than expected among Danish adolescents, comparable to other European countries, and that the majority were asymptomatic or oligosymptomatic and were only found because of the screening procedure.

Compliance to a Gluten-Free Diet in Swedish Children with Type 1 Diabetes and Celiac Disease

Children with type 1 diabetes (T1D) are at increased risk of celiac disease (CD). The replacement of insulin in T1D, and the exclusion of gluten in CD, are lifelong, burdensome treatments. Compliance to a gluten-free diet (GFD) in children with CD is reported to be high, while compliance in children with both diseases has scarcely been studied. To examine compliance to a GFD in children with both T1D and CD, we analyzed tissue transglutaminase IgA-antibodies (tTGA). Moreover, associations between compliance and age, sex, glycemic control, ketoacidosis (DKA), body mass index (BMI), and time of CD diagnosis were investigated. Of the 743 children diagnosed with T1D in southern Sweden between 2005 and 2012, 9% were also diagnosed with CD. Of these, 68% showed good compliance to a GFD, 18% showed intermediate compliance, and 14% were classified as non-compliant. Higher age, poorer HbA1c, and more DKAs were significantly (p < 0.05) associated with poorer compliance. In conclusion, we found that compliance to a GFD in children with T1D and CD is likely be lower than in children with CD only. Our results indicate that children with both T1D and CD could need intensified dietary support and that older children and children with poor metabolic control are especially vulnerable subgroups.

Clinical Presentation of Celiac Disease and Diagnosis Accuracy in a Single-Center European Pediatric Cohort over 10 Years

(1) Background: Changes in the clinical presentation of celiac disease (CD) in children have been reported. The guidelines of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) allow esophagogastroduodenoscopy (EGD) with biopsies to be avoided under specific circumstances. We aimed to assess the clinical picture of pediatric CD patients at diagnosis and to validate ESPGHAN non-biopsy criteria. (2) Methods: Patients with suspected CD or undergoing screening from 2004 to 2014 at the University Hospital in Modena, Italy were enrolled. The accuracy of ESPGHAN non-biopsy criteria and modified versions were assessed. (3) Results: In total, 410 patients were enrolled, of whom 403 were considered for analysis. Of the patients considered, 45 were asymptomatic and diagnosed with CD (11.2%) while 358 patients (88.2%) were symptomatic, of whom 295 were diagnosed with CD. Among symptomatic CD patients, 57 (19.3%) had gastrointestinal symptoms, 98 (33%) had atypical symptoms and 140 (47.4%) had both. No difference was found for the presence of gastrointestinal symptoms at different ages. The non-biopsy ESPGHAN criteria yielded an accuracy of 59.4% with a positive predictive value (PPV) of 100%; 173 out of 308 EGD (56.2%) could have been avoided. The modified 7× and 5× upper limit of normal cut-offs for IgA anti tissue-transglutaminase reached 60.7% and 64.3% of EGD avoided, respectively. (4) Conclusions: Over 10 years, late age at diagnosis and increased rates of atypical CD presentation were found. ESPGHAN non-biopsy criteria are accurate for CD diagnosis and allow half of unneeded EGD to be avoided. Modified versions allowed sparing a greater number of EGD.

Wheat consumption and prevalence of celiac disease: Correlation from a multilevel analysis

Celiac disease (CD) is triggered by both genetic and environmental factors. More than 1% of the world's population is affected by CD. In recent years, studies have confirmed a worldwide rising trend in CD prevalence. "Westernized diet" is one of the main factors of this increasing prevalence. However, the relationship between wheat consumption, its dynamics, and CD has not been adequately investigated on a global scale. This study aimed to perform a multilevel analysis of the association between wheat consumption and CD. Wheat consumption data from countries and continents were obtained from the database. The relative increase/decrease in wheat consumption over a long period (since 1961) and a short period (since 2004) were calculated using various statistical tools. The relationship between wheat consumption and celiac frequency was determined using the R-commander R package version 2.6-2. Pearson's correlation coefficient (r = 0.88) confirmed a high positive correlation between wheat consumption and the prevalence of biopsy-proven CD by estimating continent-wide wheat consumption data, but an insignificant correlation was found when the data were compared country-wide.

Is mass screening for coeliac disease a wise use of resources? A health economic evaluation

Background

Living with undiagnosed symptomatic coeliac disease is connected with deteriorated health, and persons with coeliac disease often wait a long time for their diagnosis. A mass screening would lower the delay, but its cost-effectiveness is still unclear. Our aim was to determine the cost-effectiveness of a coeliac disease mass screening at 12 years of age, taking a life course perspective on future benefits and drawbacks.

Methods

The cost-effectiveness was derived as cost per quality-adjusted life-year (QALY) using a Markov model. As a basis for our assumptions, we mainly used information from the Exploring the Iceberg of Celiacs in Sweden (ETICS) study, a school-based screening conducted in 2005/2006 and 2009/2010, where 13,279 12-year-old children participated and 240 were diagnosed with coeliac disease, and a study involving members of the Swedish Coeliac Association with 1031 adult participants.

Results

The cost for coeliac disease screening was 40,105 Euro per gained QALY. Sensitivity analyses support screening based on high compliance to a gluten-free diet, rapid progression from symptom-free coeliac disease to coeliac disease with symptoms, long delay from celiac disease with symptoms to diagnosis, and a low QALY score for undiagnosed coeliac disease cases.

Conclusions

A coeliac disease mass screening is cost-effective based on the commonly used threshold of 50,000 Euro per gained QALY. However, this is based on many assumptions, especially regarding the natural history of coeliac disease and the effects on long-term health for individuals with coeliac disease still eating gluten.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01737-1.

Family socio-economic status and childhood coeliac disease seem to be unrelated-A cross-sectional screening study

Aim

The aim of our study was to examine whether there is a difference in coeliac disease prevalence in regard to parents' education level and occupation, and whether this differs between screened and clinically diagnosed children at the age of 12 years.

Methods

The study, Exploring the Iceberg of Celiacs in Sweden (ETICS), was a school‐based screening study of 12‐year‐old children that was undertaken during the school years 2005/2006 and 2009/2010. Data on parental education and occupation were reported from parents of the children. Specifically, by parents of 10 710 children without coeliac disease, 88 children diagnosed with coeliac disease through clinical care, and 231 who were diagnosed during the study.

Results

There were no statistically significant associations between occupation and coeliac disease for either the clinically detected (prevalence ratio 1.16; confidence interval 0.76‐1.76) or screening‐detected coeliac disease cases (prevalence ratio 0.86; confidence interval 0.66‐1.12) in comparison with children with no coeliac disease. Also, there were no statistically significant associations for parental education and coeliac disease diagnosis.

Conclusion

There was no apparent relationship between coeliac disease and socio‐economic position. Using parents' socio‐economic status as a tool to help identify children more likely to have coeliac disease is not recommended.

Nonbiopsy Approach for Celiac Disease Is Accurate When Using Exact Duodenal Histomorphometry: Prospective Study in 2 Countries

GOALS

To test the accuracy of serology-based criteria for diagnosing celiac disease utilizing quantitative histomorphometry.

BACKGROUND

The revised European pediatric guidelines allow noninvasive celiac disease diagnosis for a subgroup of children. However, in some of the studies on this issue, the positive predictive value (PPV) of serology has remained suboptimal, possibly because of challenges of histopathology as the reference standard.

STUDY

Prospectively enrolled children with transglutaminase 2 antibodies (TGA) above the upper limit of normal (ULN) underwent blood sampling and duodenal biopsy in Finland and Romania. Those with TGA ≥10× ULN, positive endomysium antibodies (EmA), and disease-associated genetics were considered to fulfill triple criteria for celiac disease. Initial histopathologic analysis was conducted using grouped classification, whereupon centralized morphometry was performed.

RESULTS

Altogether 88 (54%) children were triple positive. In local evaluation, 99% of triple-positive children and 73% of children with TGA <10× ULN had celiac disease. These figures increased to 100% and 85% after more precise morphometric analysis. Triple-positive children had more anemia and higher median EmA and liver enzyme values than those with TGA<10× ULN; the groups were comparable in other clinical features and laboratory parameters.

CONCLUSIONS

When applied as recommended, the nonbiopsy strategy had already yielded excellent PPV regardless of the site of diagnosis or clinical presentation in the local analysis. PPV further increased to 100% with standardized duodenal morphometry.

Serological study of celiac disease in children with dental caries

BACKGROUND

Celiac disease is a common gastrointestinal autoimmune disorder. Studies have shown that the prevalence of tooth decay is high in patients with celiac disease. This study was performed to evaluate the serology of celiac disease in children with dental caries.

METHODS

Children aged 3 to 12 years who referred to the dental clinic with enamel caries were included in the study. Celiac disease was assessed by measuring serum IgA levels and anti-TTG (Anti TTG (IgA)) antibodies. Then, by analyzing the collected data, the prevalence of celiac disease in children with dental caries and its relationship with various variables were investigated.

RESULTS

120 children, 56 girls (46.7%) and 64 boys (53.3%) with dental caries were involved in this study. The positive celiac serology rate of studied population was 14 (11.6%). Based on the results of this study, a significant relationship was obtained between maternal education, sex and place of residence and celiac disease (p< 0.05). There were no significant relationships between celiac positive serology in children with dental caries, the number of decayed teeth, and breastfeeding (p> 0.05).

CONCLUSION

The present study showed that dental caries, might be a red flag indicating possible celiac disease and prevent its complications. On the other hand, pediatricians and dentists should be aware of the oral symptoms of celiac disease. Further studies are needed to plan screening for children with celiac disease.

Differences Between Familial and Sporadic Celiac Disease

BACKGROUND

It is not known if genetic background, characteristics at diagnosis, physical and psychological well-being, and adherence to a gluten-free diet are comparable between patients with familial or sporadic celiac disease. These issues were investigated in a follow-up study.

METHODS

Altogether 1064 patients were analyzed for celiac disease-associated serology, predisposing HLA-DQ, and non-HLA genotypes. Medical data were collected from patient records and supplementary interviews. Current symptoms and quality of life were further evaluated with the Gastrointestinal Symptom Rating Scale (GSRS), the Psychological General Well-Being questionnaire (PGWB), and Short Form 36 (SF-36) questionnaires.

RESULTS

Familial and sporadic groups differed (P < 0.001) in the reason for diagnosis and clinical presentation at diagnosis, familial patients being more often screen-detected (26% vs. 2%, P < 0.001) and having less often gastrointestinal (49% vs. 69%) and severe symptoms (47% vs. 65%). The groups were comparable in terms of histological damage, frequency of malabsorption, comorbidities, childhood diagnoses, and short-term treatment response. At the time of the study, familial cases reported fewer symptoms (21% vs. 30%, P = 0.004) and lower prevalence of all (78% vs. 86%, P = 0.007), neurological (10% vs. 15%, P = 0.013), and dermatological (9% vs. 17%, P = 0.001) comorbidities. Dietary adherence and GSRS scores were comparable, but familial cases had better quality of life according to PGWB and SF-36. High-risk genotype HLA-DQ2.5/DQ2.5 was more frequent among familial cases, and four non-HLA SNPs were associated with familial celiac disease.

CONCLUSIONS

Despite the greater proportion of high-risk genotypes, familial cases had milder symptoms at presentation than did sporadic cases. Worse experience of symptoms and poorer quality of life in sporadic disease indicate a need for intensified support.

Conduct disorder and somatic health in children: a nationwide genetically sensitive study

BACKGROUND

Conduct disorder (CD), a serious behavioral and emotional disorder in childhood and adolescence, characterized by disruptive behavior and breaking societal rules. Studies have explored the overlap of CD with neurodevelopmental problems (NDP). The somatic health of children with NDP has been investigated; however, the prevalence of these problems in children with CD has not been sufficiently studied. Holistic assessment of children with CD is required for establishing effective treatment strategies.

AIMS

(1) Define the prevalence of selected neurological problems (migraine and epilepsy) and gastrointestinal problems (celiac disease, lactose intolerance, diarrhea, and constipation) in a population of twins aged 9 or 12; (2) Compare the prevalence of somatic problems in three subpopulations: (a) children without CD or NDP, (b) children with CD, and (c) children with both CD and NDP; (3) Select twin pairs where at least one child screened positive for CD but not NDP (proband) and map both children's neurological and gastrointestinal problems.

METHOD

Telephone interviews with parents of 20,302 twins in a cross-sectional, nationwide, ongoing study. According to their scores on the Autism-Tics, AD/HD, and Comorbidities inventory, screen-positive children were selected and divided into two groups: (1) children with CD Only, (2) children with CD and at least one NDP.

RESULTS

Children with CD had an increased prevalence of each neurological and gastrointestinal problem (except celiac disease), and the prevalence of somatic problems was further increased among children with comorbid CD and NDP. The presence of CD (without NDP) increased the odds of constipation for girls and the odds of epilepsy for boys. Girls with CD generally had more coexisting gastrointestinal problems than boys with CD. Female co-twins of probands with CD were strongly affected by gastrointestinal problems. Concordance analyses suggested genetic background factors in neurological and gastrointestinal problems, but no common etiology with CD could be concluded.

CONCLUSION

Co-occurring NDP could explain most of the increased prevalence of somatic problems in CD. Our results raise a new perspective on CD in children and adolescents; their CD seems to be linked to a number of other health problems, ranging from neurodevelopmental and psychiatric disorders to somatic complaints.

Prevalence and clinical significance of esophageal abnormalities in children with celiac disease

Variable endoscopic and histological findings of esophageal lining are often detected in celiac disease, with unknown significance. We investigated the frequency and significance of such abnormalities in children. Macroscopic esophageal findings as reported by endoscopist and histological results by pathologist were compared between 316 celiac disease patients and 378 disease controls who had undergone upper gastrointestinal endoscopy with systematic esophageal biopsy sampling. Association between esophageal abnormalities and other clinical and histological characteristics of the disease was evaluated in celiac disease patients. Endoscopic esophageal findings were reported least often (3.8%) of all diseases in celiac disease, whereas histopathologic abnormalities were frequent (16.8%, n = 53). Children with celiac disease and esophageal histopathology reported more reflux than those with normal esophagus (5.7 vs. 0.8%, P = 0.032), whereas the groups were comparable in the frequency and severity of other symptoms, demographic data, prevalence of celiac disease-associated and other coexisting chronic conditions, family history of celiac disease, anthropometric and laboratory parameters, and degree of villous atrophy. Only 2 (3.7%) out of the 53 children with histologic findings had esophageal symptoms at diagnosis, and altogether seven were treated with acid blockers. Four children had increased number (≥15 eosinophils per high-power field) of esophageal eosinophils, but none of them had definite eosinophilic esophagitis. The remaining 45 children had only unspecific inflammation in the esophagus and reported no esophageal problems during a median of 6.9 years follow-up. To conclude, although relatively common, histopathological esophageal findings in celiac disease are mostly unspecific and without major clinical significance even in a long-term follow-up.

Distribution of HLA-DQ risk genotypes for celiac disease in Ethiopian children

Most patients with celiac disease are positive for either HLA‐DQA1*05:01‐DQB1*02 (DQ2.5) or DQA1*03:01‐DQB1*03:02 (DQ8). Remaining few patients are usually DQA1*02:01‐DQB1*02 (DQ2.2) carriers. Screenings of populations with high frequencies of these HLA‐DQA1‐DQB1 haplotypes report a 1% to 3% celiac disease prevalence. The aim was to determine the prevalence of HLA‐DQ risk haplotypes for celiac disease in Ethiopian children. Dried blood spots collected from 1193 children from the Oromia regional state of Ethiopia were genotyped for HLA‐DQA1 and DQB1 genotyping using an asymmetric polymerase chain reaction (PCR) and a subsequent hybridization of allele‐specific probes. As references, 2000 previously HLA‐genotyped children randomly selected from the general population in Sweden were included. DQ2.2 was the most common haplotype and found in 15.3% of Ethiopian children, which was higher compared with 6.7% of Swedish references (P < .0001). Opposed to this finding, DQ2.5 and DQ8 occurred in 9.7% and 6.8% of Ethiopian children, which were less frequent compared with 12.8% and 13.1% of Swedish references, respectively (P < .0001). The DQ2.5‐trans genotype encoded by DQA1*05‐DQB1*03:01 in combination with DQ2.2 occurred in 3.6% of Ethiopian children, which was higher compared with 1.3% of Swedish references (P < .0001). However, when children with moderate high to very high‐risk HLA genotypes were grouped together, there was no difference between Ethiopian children and Swedish references (27.4% vs 29.0%) (P = .3504). The frequency of HLA risk haplotypes for celiac disease is very similar in Ethiopian and Swedish children. This finding of importance will be useful in future screening of children for celiac disease in Ethiopia.

Maternal fibre and gluten intake during pregnancy and risk of childhood celiac disease: the MoBa study

Maternal diet can influence the developing immune system of the offspring. We hypothesized that maternal fibre and gluten intake during pregnancy were associated with the risk of celiac disease in the child. In the Norwegian Mother, Father and Child Cohort Study (MoBa, n = 85,898) higher maternal fibre intake (median 29.5 g/day) was associated with a lower risk of celiac disease in the offspring (adjusted relative risk 0.90, 95% CI 0.83 to 0.98 per 10 g/d increase). Gluten intake during pregnancy (median 13.0 g/d) was associated with a higher risk of childhood CD (adjusted relative risk = 1.21, 95% CI 1.02 to 1.43 per 10 g/d increase). These results were largely unaffected by adjustment for the child’s gluten intake at 18 months. In an independent study of 149 mother/child dyads, maternal fibre intake did not predict concentrations of total or sub-types of short-chain fatty acids in repeated infant stool samples, or fecal microbiome diversity in the mother or child. Our results suggest that high fibre and low gluten intake during pregnancy could be protective factors for celiac disease, although the mechanism is unknown.

Incidence of Celiac Disease in Down Syndrome: A Longitudinal, Population-Based Birth Cohort Study

American Academy of Pediatrics (AAP) guidelines for children with Down syndrome (DS) include assessment for celiac disease (CD), although data to support this recommendation have been inconsistent. We determined the incidence of CD among children with DS in a population-based birth cohort of children born from 1976 to 2000 in Olmsted County, Minnesota. Individuals with karyotype-confirmed DS and CD (using diagnosis codes, positive serology, and duodenal biopsies) were identified. The incidence of CD in DS was compared with the published incidence of CD for Olmsted County residents (17.4 [95% confidence interval = 15.2-19.6] per 100 000 person-years). Among 45 individuals with DS from the birth cohort, 3 (6.7%) were identified with positive celiac serology and confirmatory biopsies at ages 9, 12, and 23 years, for an incidence of 325 per 100 000 person-years. Thus, individuals with DS have more than 18 times the incidence rate of CD compared with the general population, supporting the AAP guidelines.

Persistent Alterations in Plasma Lipid Profiles Before Introduction of Gluten in the Diet Associated With Progression to Celiac Disease

Celiac disease (CD) is a chronic enteropathy characterized by an autoimmune reaction in the small intestine of genetically susceptible individuals. The underlying causes of autoimmune reaction and its effect on host metabolism remain largely unknown. Herein, we apply lipidomics to elucidate the early events preceding clinical CD in a cohort of Finnish children, followed up in the Type 1 Diabetes Prediction and Prevention study.

Should the Glu Be Ten or Twenty? An Update on the Ongoing Debate on Gluten Safety Limits for Patients with Celiac Disease

The only currently accepted and recommended treatment for individuals diagnosed with celiac disease (CD) is a strict life-long gluten-free diet (GFD). While the use of the GFD is well-established, strict adherence to diet is not easy to accomplish. In addition, the administration of a GFD may be compromised by inadvertent exposure to small amounts of gluten. International guidelines define a gluten-free product as one containing less than 20 parts per million (ppm), (20 milligrams of gluten per 1 kg of food) gluten. A number of reports have assessed the safe upper limit for gluten exposure for patients with CD, with general consensus that patients with CD should limit their daily intake to less than 50 mg.

The Impact of Parental Diabetes on the Prevalence of Childhood Obesity

Background: Obesity among children and adolescents is a worldwide public health concern. Type 1 diabetes (T1D) and type 2 diabetes (T2D) incidence are increasing, with heredity and socioeconomic status as possible risk factors. How these factors affect the risk of childhood obesity remains unclear. The aim of this study was to investigate the association between obesity and parental diabetes among 12-year-olds in Sweden, and how it relates to parental education level. Methods: We used data collected within the Exploring the Iceberg of Celiacs in Sweden (ETICS) study, a cross-sectional multicenter national screening study for celiac disease in 12-year-old children. Relative risk (RR) and confidence interval (CI) were calculated for the association between parental diabetes and obesity, also stratifying for gender and highest parental education. Results: Among 11,050 children, for both children with parental T1D and T2D, 31% of the children were overweight or obese, compared with 21% among other children. Comparing those with parental T1D with those without parental T1D within gender, boys had a statistically significant higher risk [RR 1.6 (95% CI 1.3-2.0)], and girls had a nonsignificant increased risk [RR 1.3 (95% CI 0.95-1.8)], of being overweight. For children with parental T2D, both boys and girls had a statistically significant increased risk of 1.5. Parental education showed no sign of influencing the RRs. Conclusions: Parental diabetes is associated with an increased risk of overweight among children, independent of parental education. Concomitant parental diabetes and overweight should be particularly alarming criteria when prioritizing preventive interventions at an early age.

Intestinal Anti-tissue Transglutaminase2 Autoantibodies: Pathogenic and Clinical Implications for Celiac Disease

Celiac disease (CD) is a systemic disease that primarily affects the small intestine. The presence of anti-tissue transglutaminase 2 (anti-TG2) antibodies in the serum, as well as the presence of autoimmune phenomena, account for the inclusion of CD among autoimmune diseases. Anti-TG2 autoantibodies are produced at intestinal level, where they are deposited even before they appear in circulation. The pathogenic events that lead to their production are still not completely defined, but a central role seems to be played by gliadin-specific T cells. Interestingly, limited somatic mutations have been observed in VH and VL genes in TG2-specific plasma cells, another important aspect being the biased use of a heavy chain encoded by the VH5 gene. Conflicting data have been produced over the years on the effect of anti-TG2 antibodies on TG2 function. Although the presence of anti-TG2 antibodies in serum is considered a hallmark of CD and relevant from a clinical viewpoint, the role of these autoantibodies in the development of the celiac lesion remains to be defined. In the years, different technical approaches have been implemented to detect and measure intestinal CD-associated autoantibody production. Two aspects can make intestinal anti-TG2 antibodies relevant: from a clinical viewpoint: the first is their proposed ability in potential coeliac patients to predict the development of a full-blown enteropathy; the second is their possible role in revealing a condition of reactivity to gluten in patients with no circulating CD-associated autoantibodies. In fact, the detection of CD-specific autoantibodies production in the intestine, in the absence of serum positivity for the same antibodies, could be suggestive of a very early condition of gluten reactivity; alternatively, it could be not specific for CD and merely attributable to intestinal inflammation. In conclusion, the role of mucosal anti-TG2 antibodies in pathogenesis of CD is unknown. Their presence, the modalities of their production, their gluten dependence render them a unique model to study autoimmunity.

Incidence of Celiac Disease Is Increasing Over Time: A Systematic Review and Meta-analysis

OBJECTIVES

To conduct a systematic review and meta-analysis that defines the worldwide incidence of celiac disease (CD) and examines temporal trends.

METHODS

MEDLINE and EMBASE were searched for population-based studies reporting the incidence of CD in the overall population, children, or adults. No limits were placed on year or language of publication. Studies solely examining at-risk populations (e.g., patients with type 1 diabetes) were excluded. Random-effects models were performed to meta-analyze sex- and age-specific incidence in the 21st century. Temporal trend analyses assessed the average annual percent change in CD incidence over time.

RESULTS

Of 11,189 citations, 86 eligible studies were identified for inclusion, of which 50 were deemed suitable for analyses. In the 21st century, the pooled female incidence of CD was 17.4 (95% confidence interval [CI]: 13.7, 21.1) (I = 99.5%) per 100,000 person-years, compared with 7.8 (95% CI: 6.3, 9.2) (I = 98.6%) in males. Child-specific incidence was 21.3 per 100,000 person-years (95% CI: 15.9, 26.7) (I = 99.7%) compared with 12.9 (95% CI: 7.6, 18.2) (I = 99.9%) in adults. Pooling average annual percent changes showed the incidence of CD to be increasing by 7.5% (95% CI: 5.8, 9.3) (I = 79.6%) per year over the past several decades.

DISCUSSION

Incidence of CD is highest in females and children. Overall, the incidence has been significantly rising in the latter half of the 20th century and into the 21st century throughout the Western world. Population-based studies in Africa, Asia, and Latin America are needed to provide a comprehensive picture of the global incidence of CD.

Increased Prevalence of Celiac Disease in School-age Children in Italy

BACKGROUND & AIMS

Celiac disease is one of the most common diseases worldwide, with an apparent trend of increasing prevalence. We investigated the prevalence of celiac disease in children in Italy in 2015-2016 and compared that with data from 25 years ago.

METHODS

We screened 4570 children (5-11 years old, 80.1% of the eligible population) from metropolitan areas of Ancona and Verona for HLA genes associated with increased risk of celiac disease, and for total serum levels of IgA and IgA class anti-tissue transglutaminase in HLA positives. Diagnoses of celiac disease were confirmed by detection of anti-endomysial antibody and analysis of intestinal biopsies. The prevalence of celiac autoimmunity and celiac disease were calculated and compared with values from the same geographical area during the years 1993-1995, after adjustment for the different diagnostic algorithm.

RESULTS

We identified 1960 children with celiac disease-associated haplotypes (43% of children screened; 95% CI, 40.8%-45.2%). The prevalence of celiac disease autoimmunity in the HLA-positive subjects was 96/1706 (5.62%; 95% CI, 4.53%-6.71%) and 54 of these children satisfied the diagnostic criteria for celiac disease. In the eligible population there were other 23 known cases of celiac disease. The overall estimated prevalence of celiac disease was 1.58% (95% CI, 1.26%-1.90%); this value is significantly higher than the 1993-1995 adjusted prevalence (0.88%; 95% CI, 0.74%-1.02%).

CONCLUSIONS

We found the prevalence of celiac disease in children in Italy to be greater than 1.5%; this value has increased significantly over the past 25 years. Studies are needed to determine the causes of this large increase.

Prevalence and diagnostic outcomes of children with duodenal lesions and negative celiac serology

BACKGROUND

Celiac disease diagnostics begin by measuring autoantibodies, which may fail to identify seronegative patients. Duodenal lesion in the absence of antibodies is scarcely studied, especially in children.

AIMS

To investigate the prevalence and diagnostic outcomes of children with seronegative duodenal lesion in two countries with different disease profiles.

METHODS

Medical data, including the results of histology and transglutaminase (tTGab) and endomysium (EmA) antibody measurements were collected from 1172 Finnish and 264 Romanian children with systematic duodenal sampling. Database of 509 Finnish children with celiac disease was examined to identify earlier seronegative patients.

RESULTS

Celiac disease was diagnosed in 307 Finnish and 83 Romanian children in the endoscopy cohorts. No seronegative patients were found among 899 celiac disease patients, although some were only tTGab or EmA positive. Non-celiac duodenal lesion was detected in eight Finnish and 32 Romanian children, their most common diagnoses being inflammatory bowel disease and infections, respectively. Six children with morphological lesion received no diagnosis. None of them developed celiac disease during a follow-up of 3-11 years.

CONCLUSION

Pediatric seronegative celiac disease is exceptional in the era of modern autoantibodies. Other reasons for duodenal lesion should therefore be sought, bearing in mind possible differences across countries.

Elevated Levels of 1,25-Dihydroxyvitamin D in Plasma as a Missing Risk Factor for Celiac Disease

The prevalence of celiac disease (CD) has increased significantly in some developed countries in recent decades. Potential risk factors that have been considered in the literature do not appear to provide a convincing explanation for this increase. This has led some researchers to hypothesize that there is a "missing environmental factor" that increases the risk of CD. Based on evidence from the literature, the author proposes that elevation in plasma levels of 1,25-dihydroxyvitamin D [1,25(OH)₂D] is a missing risk factor for CD, and relatedly that significant oral vitamin D exposure is a "missing environmental factor" for CD. First, elevated plasma levels of 1,25(OH)₂D are common in CD, especially in the newly diagnosed. Second, nine distinct conditions that increase plasma levels of 1,25(OH)₂D are either associated with CD or have indications of such an association in the literature. Third, a retrospective study shows that sustained oral vitamin D supplementation in infancy is associated with increased CD risk, and other studies on comorbid conditions support this association. Fourth, large doses of oral vitamin D upregulate many of the same cytokines, chemokines, and toll-like receptors that are upregulated in CD. Fifth, epidemiological evidence, such as the timing of the inception of a CD "epidemic" in Sweden, the increased prevalence of CD in Finland and the United States in recent decades, the unusually low prevalence of CD in Germany, and the differential in prevalence between Finnish Karelians and Russian Karelians, may all be explained by oral vitamin D exposure increasing CD risk. The same is true of some seemingly contradictory results in the literature on the effects of breastfeeding on CD risk. If future research validates this hypothesis, adjustments to oral vitamin D consumption among those who have genetic susceptibility may decrease the risk of CD in these individuals.

Celiac Dietary Adherence Test simplifies Determining Adherence to a Gluten-free Diet in Swedish Adolescents

OBJECTIVES

The aims of the study were to ascertain whether the Celiac Dietary Adherence Test (CDAT) could contribute in determining adherence to a gluten-free diet in patients with celiac disease and to evaluate the diet adherence and well being of a study population 5 years after a celiac disease screening known as "Exploring the Iceberg of Celiacs in Sweden."

METHODS

Through the screening, 90 adolescents (born 1997) were diagnosed with biopsy-proven celiac disease at 12 years of age. Of them, 70 (78%) came to a 5-year follow-up where anti-tissue transglutaminase antibodies 2 was tested and a questionnaire was filled in, including CDAT, which consists of 7 questions related to adherence. Nonparametrical tests were used to determine associations between adherence measures.

RESULTS

Among the adolescents, 86% were adherent to a gluten-free diet 5 years after screening, 38% reported their general well being as excellent, 50% very well, and 12% well. Statistically significant associations were seen between anti-tissue transglutaminase antibodies 2 and the CDAT score (P = 0.033), and the self-reported adherence question and the CDAT score (P < 0.001).

CONCLUSIONS

The screening-detected adolescents reported a high level of well being and adherence to a gluten-free diet 5 years after screening. We conclude that the CDAT can be used in clinical practice as an estimation of adherence to a gluten-free diet. It would be most suitable to use in conjunction with currently used adherence measures, but can also be used as a stand-alone method when others are not accessible.

Sex Difference in Celiac Disease in Undiagnosed Populations: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

A higher proportion of female vs male patients receive a diagnosis of celiac disease. Little is known about sex-based differences in the prevalence of celiac disease in undiagnosed populations. We aimed to address this knowledge gap with a systematic review and meta-analysis.

METHODS

We searched MEDLINE, Embase, Cochrane, and Scopus databases through 2017 for studies of screen-detected or undiagnosed celiac disease. Our final analysis included studies that included screening and confirmatory tests (either second serologic analysis or a small intestine biopsy) and provided information on the sex of participants. Studies were excluded if they were performed with specific, high-risk, or referral populations. The primary outcome was the percentage of undetected celiac disease among female and male patients.

RESULTS

We identified 4070 articles and analyzed data from 87. Our meta-analysis comprised data from 291,969 study participants. The pooled prevalence of undetected celiac disease in female participants was 0.589% (95% CI, 0.549%-0.629%) and in male participants was 0.415% (95% CI, 0.343%-0.487%). The risk of undetected celiac disease was higher among female than male participants (relative risk [RR], 1.42; 95% CI, 1.27-1.57; P < .00001). The I² was 5% (low heterogeneity among studies). In subgroup analyses, the RR of celiac disease for girls vs boys was 1.79 (95% CI, 1.44-2.22; P < .00001; I² = 18%), the RR for female vs male blood donors was 1.13 (95% CI, 0.76-1.69; P = .54; I² = 0), and the RR for women vs men with villous atrophy was 1.38 (95% CI, 1.07-1.79; P = .01; I² = 0).

CONCLUSIONS

In a systematic review and meta-analysis, we found a higher risk for celiac disease in women than men in an undiagnosed populations (identified through general population screening). The increased risk for celiac disease among girls and women should be considered for screening, diagnosis, and management strategies.

Changing Pattern of Childhood Celiac Disease Epidemiology: Contributing Factors

Up until the 1960s and 1970s, diarrhea, malabsorption syndrome, and failure to thrive were the presenting symptoms and signs of celiac disease (CD) in young infants; however this disease was also at the same time reported to be disappearing. Indeed, clinical childhood CD was seen to transform into a milder form, resulting in an upward shift in age at diagnosis during the 1970s (and years later for many countries). This changing pattern of CD presentation then altered the epidemiology of the disease, with major differences between and within countries observed. An awareness of the changing clinical nature of CD and use of case-finding tools to detect even clinically silent CD became an important factor in this changing epidemiology. Countries report both low and high prevalence but it seems to be on the increase resulting in a population-based level of 1-2%. This paper discusses the potential causes and environmental factors behind these observed clinical changes, identifying new clues from different studies published at the time this transformation took place. For instance, it was found that breastfeeding postponed the diagnosis of the disease but did not altogether prevent it. Moreover, gluten introduction at a young age, specifically at the mean age of 2 months, seemed to also have a clear impact in inducing malabsorption syndrome and failure to thrive in young infants in addition to other factors such as gluten intake volume and type of cereal present in the weaning food. Further, the impact of cow's milk and its high osmolarity might have played an important role; humanized milk formulas were not yet invented. Future epidemiological studies on the contributing environmental factors to the shift in CD presentation are thus recommended for countries in which these changing clinical features are still being observed.

Diagnosing Celiac Disease: Towards Wide-Scale Screening and Serology-Based Criteria?

Celiac disease is one of the most common food-related chronic disorders in children. Unfortunately, this multifaceted disease is challenging to recognize and remains markedly underdiagnosed. Screening of either known at-risk groups or even the whole population could increase the suboptimal diagnostic yield substantially. Many recent guidelines recommend screening of at least selected risk groups, but more wide-scale screening remains controversial. The increasing prevalence of celiac disease and the development of autoantibody assays have also led to a gradual shift in the diagnostics towards less invasive serology-based criteria in a subgroup of symptomatic children. The main open questions concern whether these criteria are applicable to all countries and clinical settings, as well as to adult patients. On the other hand, widening screening and the mistaken practice of initiating a gluten-free diet before the appropriate exclusion of celiac disease increase the number of borderline seropositive cases, which may also challenge the classical histopathological diagnostics. Sophisticated diagnostic methods and a deeper understanding of the natural history of early developing celiac disease may prove useful in these circumstances.

Questionnaire showed that Swedish paediatric clinics complied well with the revised European guidelines for diagnosing coeliac disease

AIM

In 2012, revised criteria for diagnosing childhood coeliac disease were published by the European Society for Paediatric Gastroenterology, Hepatology and Nutrition and incorporated into the revised Swedish guidelines the same year. These made it possible, in certain cases, to diagnose coeliac disease without taking small bowel biopsies. This survey assessed the extent to which the new guidelines were implemented by Swedish paediatric clinics two years after their introduction.

METHODS

In October 2014, we distributed a paper questionnaire including five questions on diagnostic routines to the 40 paediatric clinics in university or regional hospitals in Sweden that perform small bowel biopsies.

RESULTS

All 36 (90%) clinics that responded used anti-tissue transglutaminase antibodies as the initial diagnostic test and some also used serological markers. Most clinics (81%) used endoscopy and took multiple duodenal biopsies, whereas only a few (19%) occasionally employed a suction capsule. Almost all clinics (86%) omitted taking small bowel biopsies in symptomatic children with repeatedly high coeliac serology and positive genotyping, thereby avoiding the need for invasive endoscopy under anaesthesia.

CONCLUSION

The 2012 Swedish Paediatric Coeliac Disease Diagnostic Guidelines had been widely accepted and implemented in routine health care two years after their introduction.

Smoking in pregnancy, cord blood cotinine and risk of celiac disease diagnosis in offspring

Ecological observations suggest an inverse relationship between smoking in pregnancy and celiac disease (CD) in offspring. While individual-level analyses have been inconsistent, they have mostly lacked statistical power or refined assessments of exposure. To examine the association between pregnancy-related smoking and CD in the offspring, as well as its consistency across data sets, we analyzed: (1) The Norwegian Mother and Child Cohort (MoBa) of 94,019 children, followed from birth (2000–2009) through 2016, with 1035 developing CD; (2) a subsample from MoBa (381 with CD and 529 controls) with biomarkers; and (3) a register-based cohort of 536,861 Norwegian children, followed from birth (2004–2012) through 2014, with 1919 developing CD. Smoking behaviors were obtained from pregnancy questionnaires and antenatal visits, or, in the MoBa-subsample, defined by measurement of cord blood cotinine. CD and potential confounders were identified through nationwide registers and comprehensive parental questionnaires. Sustained smoking during pregnancy, both self-reported and cotinine-determined, was inversely associated with CD in MoBa (multivariable-adjusted [a] OR = 0.61 [95%CI, 0.46–0.82] and aOR = 0.55 [95%CI, 0.31–0.98], respectively); an inverse association was also found with the intensity of smoking. These findings differed from those of our register-based cohort, which revealed no association with sustained smoking during pregnancy (aOR = 0.97 [95%CI, 0.80–1.18]). In MoBa, neither maternal smoking before or after pregnancy, nor maternal or paternal smoking in only early pregnancy predicted CD. In a carefully followed pregnancy cohort, a more-detailed smoking assessment than oft-used register-based data, revealed that sustained smoking during pregnancy, rather than any smoking exposure, predicts decreased likelihood of childhood-diagnosed CD.

Screening for coeliac disease in children and adults living in a slum of Dhaka, Bangladesh

Background and objective

Serological screening with a confirmation through biopsy has improved the understanding of coeliac disease (CD) epidemiology worldwide. Prevalence of CD in Bangladesh is not yet explored and therefore, we aimed to assess the seroprevalence of CD in slum-dwelling malnourished children and adults in Dhaka.

Methods

Serum samples were collected from three different cohorts: stunted (length-for-age Z-scores (LAZ) <−2) and at risk of stunting children (LAZ <−1 to −2) and malnourished adults (body mass index <18.5 kg/m²). Samples from all the participants were assessed for anti-tissue transglutaminase antibody (tTG-IgA) and total serum IgA by ELISA. Positive tTG-IgA and randomly selected low IgA values were reconfirmed using anti-tTG-IgG and gliadin IgG ELISA. CD was diagnosed when second screening tests were found positive and the participants were further investigated by small bowel biopsy.

Results

A total of 818 participants (240 stunted, 272 at risk of stunting children and 306 malnourished adults) were enrolled in the study. Overall, anti-tTG-IgA was positive in 5/818 (0.6%; 95% CI 0.25% to 1.46%). Of the five positive cases, anti-tTG-IgG and gliadin IgG were found positive in only one participant. Duodenal biopsy of positive participant revealed characteristic lesions of CD. Randomly selected low IgA values were found negative in tTG-IgG and gliadin IgG for all the participants. No participant was found total IgA deficient.

Conclusion

The incidence of coeliac autoimmunity is low in malnourished slum dwellers regardless of age in Bangladesh. It is important to investigate the nationwide prevalence to reveal the definite picture.