Screening of the adult population in Iran for coeliac disease: comparison of the tissue-transglutaminase antibody and anti-endomysial antibody tests

The Correlation Between Serum Anti-tissue Transglutaminase (Anti-tTG) Antibody Levels and Histological Severity of Celiac Disease in Adolescents and Adults: A Meta-Analysis

Celiac disease is an autoimmune disorder characterized by a broad spectrum of histological damage to the intestinal mucosa. Comprehension and understanding of the association between anti-tissue transglutaminase (anti-tTG) antibody levels and the histological severity of celiac disease are not well established, prompting the need for meta-analysis. This study aims to offer insights into the diagnostic abilities of anti-tTG antibody levels in determining the histological severity of celiac disease by providing quantitative evidence based on a diverse range of studies. An extensive search was conducted across four electronic research databases to identify primary research articles reporting serum anti-tTG antibody levels in correlation with different Marsh grades, signifying the histological severity of celiac disease. The software tool RevMan 5.4 (the Cochrane Collaboration, London, UK) was used to compile standardized mean differences (SMD) alongside their respective confidence intervals. A total of 13 studies were included in the meta-analysis, with a patient pool of 2505 patients. Marsh grade I and II were found to have higher anti-tTG antibody levels compared to those with grade 0 (SMD 1.50; 95% CI: 1.12, 1.87; p-value <0.00001). Antibody levels were higher in Marsh grade IIIa when compared to both grade 0 (SMD 0.97; 95% CI: 0.67, 1.28; p-value <0.00001) and grade ≤2 (SMD 0.61; 95% CI: 0.44, 0.79; p-value <0.00001). Patients with Marsh IIIb also reported greater anti-tTG levels compared to grade 0 (SMD 1.48; 95% CI: 0.99, 1.96; p-value <0.00001) and grade ≤2 (SMD 0.98; 95% CI: 0.79, 1.18; p-value <0.00001). Likewise, Marsh grade ≥IIIc reported high levels of anti-tTG antibodies in comparison with grade 0 (SMD 1.06; 95% CI: 0.72, 1.39; p-value <0.00001) and grade ≤2 (SMD 1.18; 95% CI: 1.02, 1.34; p-value <0.00001). Our meta-analysis revealed a consistent, robust correlation between anti-tTG antibody levels and the histological severity of celiac disease, with a clear trend of increasing antibody levels corresponding to the severity of mucosal damage. Large-scale primary research initiatives are needed to reach definitive conclusions.

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.

Epidemiological, Endoscopic, Clinical, and Pathological Features of Patients with Celiac Diseases in Southern Littoral of Caspian Sea

Background: Celiac disease is an autoimmune disorder resulting from gluten consumption in genetically predisposed individuals. The present study investigated the epidemiological, endoscopic, and clinicopathological features of patients with celiac disease in the southern littoral of the Caspian Sea. Methods: 140 patients with celiac disease were interviewed and examined regarding demographic characteristics, clinical symptoms, and serologic, endoscopic, and pathological findings. Results: 44 (31.4%) of the patients were male and 68.6% were female. The mean age of the patients at diagnosis was 27.13±13.4 years (ranging from 2 to 60 years). The most common gastrointestinal (GI) symptoms were bloating (47.8%), abdominal pain (47.1%) and diarrhea (30.7%), respectively. Also, 17 (12.1%) patients did not complain of any GI symptoms.18 (12.8%) patients had aphthous stomatitis, 10.7% had dermatitis herpetiformis, 3.6% suffered from itching without a rash, two (1.4%) mentioned psoriasis and one (0.7%) had lichen planus. 19 (19.7%) of the female patients complained of menstrual bleeding disorders, 4% mentioned infertility, and 2% experienced primary amenorrhea. The most common comorbid condition was hypothyroidism in 16 (11.4%) patients. The most common endoscopic finding was duodenal scalloping (37.25%). In addition, 7.8% of the patients had a normal endoscopic appearance. 43 (30.7%) patients were classified as Marsh IIIC, 25.7% Marsh IIIB, 17.8% Marsh IIIA, 12.8% Marsh II and 12.8% were classified as Marsh I. Conclusion: Since celiac disease can present with non-GI manifestations and the majority of our patients had Marsh III classification, it seems that celiac disease must be considered as a routine screening test in GI clinics, and also, it should be kept in mind as a differential diagnosis in other specialty fields.

Anemia in Celiac Disease: Prevalence, Associated Clinical and Laboratory Features, and Persistence after Gluten-Free Diet

Anemia is considered to be the most frequent extra-intestinal manifestation of Celiac Disease (CD). We assessed frequency, severity, morphologic features, and pathogenic factors of anemia in patients of the Sicilian Regional Network of Celiac Disease and attempted to identify putative pre-diet factors influencing anemia persistence. We retrospectively analyzed CD patients admitted to three centers between 2016–2020. 159 patients entered the study (129 females). More than half (54.7%) had mild-moderate, hypochromic and microcytic anemia, associated with below normal total serum iron and ferritin, indicative of iron deficiency anemia (IDA). One year after diagnosis, 134 patients were following ‘strict’ GFD. Hypochromic and microcytic anemia persisted in 46% of subjects who were anemic at diagnosis. Patients with persistent anemia had at diagnosis a higher prevalence of female gender (p = 0.02), lower body mass index (BMI, p = 0.01), higher prevalence of poly/hypermenorrhea (p = 0.02) and atopy (p = 0.04), and lower ferritin levels (p = 0.05) than the whole group of non-anemic ones. IDA is found in more than 50% of CD patients at diagnosis; nevertheless, in a lot of women IDA is not corrected by ‘strict’ GFD. Low BMI and poly/hypermenorrhea at diagnosis characterize this subgroup, suggesting that IDA might be due to iron loss rather than malabsorption, or to their coexistence/overlap.

Prevalence of celiac disease in patients with atypical presentations

BACKGROUND AND STUDY AIMS

Unawareness about atypical forms of celiac disease (CD) leads to the underdiagnoses of CD. This study has investigated the prevalence of CD in patients with atypical presentations, such as idiopathic low bone mineral density (ILBMD) and dyspepsia, in the Iranian population.

PATIENTS AND METHODS

Two separate groups of patients who have been diagnosed with dyspepsia and ILBMD (including either osteopenia or osteoporosis of unknown cause) were screened for CD during 2016-2019. Patients were serologically screened by means of IgA anti-tissue transglutaminase (IgA anti-tTG); in case of positive results, the patients underwent endoscopic intestinal biopsy to confirm the diagnosis of CD.

RESULTS

Of 200 patients with ILBMD, six (3%) had a positive result for IgA anti-tTG; in five cases (2.5%), duodenal histology confirmed the CD diagnosis. Of 290 patients with dyspepsia, 25 (8.6%) had a positive result for anti-tTG IgA; nine cases (3.7%) were histologically compatible with CD. No significant differences were found between the two groups of patients.

CONCLUSIONS

The prevalence of CD in patients with atypical presentations, such as ILBMD and dyspepsia, is consistent (pvalue = 0.788) and higher than that in the general population (p value = 0.001); therefore, screening program for CD in these patients is highly recommended.

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.

Prevalence of Celiac Disease in Patients With Turner Syndrome: Systematic Review and Meta-Analysis

Introduction: Celiac disease (CD) is a multifactorial autoimmune disorder, and studies have reported that patients with Turner syndrome (TS) are at risk for CD. This systematic review and meta-analysis aimed to quantify the weighted prevalence of CD among patients with TS and determine the weighted strength of association between TS and CD.

Methods: Studies published between January 1991 and December 2019 were retrieved from four electronic databases: PubMed, Scopus, Web of Science, and Embase. Eligible studies were identified and relevant data were extracted by two independent reviewers following specific eligibility criteria and a data extraction plan. Using the random-effects model, the pooled, overall and subgroup CD prevalence rates were determined, and sources of heterogeneity were investigated using meta-regression.

Results: Among a total of 1,116 screened citations, 36 eligible studies were included in the quantitative synthesis. Nearly two-thirds of the studies (61.1%) were from European countries. Of the 6,291 patients with TS who were tested for CD, 241 were diagnosed with CD, with a crude CD prevalence of 3.8%. The highest and lowest CD prevalence rates of 20.0 and 0.0% were reported in Sweden and Germany, respectively. The estimated overall weighted CD prevalence was 4.5% (95% confidence interval [CI], 3.3–5.9, I², 67.4%). The weighted serology-based CD prevalence in patients with TS (3.4%, 95% CI, 1.0–6.6) was similar to the weighted biopsy-based CD prevalence (4.8%; 95% CI, 3.4–6.5). The strength of association between TS and CD was estimated in only four studies (odds ratio 18.1, 95% CI, 1.82–180; odds ratio 4.34, 95% CI, 1.48–12.75; rate ratio 14, 95% CI, 1.48–12.75; rate ratio 42.5, 95% CI, 12.4–144.8). Given the lack of uniformity in the type of reported measures of association and study design, producing a weighted effect measure to evaluate the strength of association between TS and CD was unfeasible.

Conclusion: Nearly 1 in every 22 patients with TS had CD. Regular screening for CD in patients with TS might facilitate early diagnosis and therapeutic management to prevent adverse effects of CD such as being underweight and osteoporosis.

Prevalence of celiac disease in low and high risk population in Asia-Pacific region: a systematic review and meta-analysis

This systematic review and meta-analysis study was conducted to estimate the pooled prevalence of CD in low and high risk groups in this region. Following keywords were searched in the Medline, PubMed, Scopus, Web of Science and Cochrane database according to the MeSH terms; celiac disease, prevalence, high risk population and Asian-Pacific region. Prevalence studies published from January 1991 to March 2018 were selected. Prevalence of CD with 95% confidence interval (CI) was calculated using STATA software, version 14. The pooled sero-prevalence of CD among low risk group in Asia-Pacific region was 1.2% (95% CI 0.8-1.7%) in 96,099 individuals based on positive anti-tissue transglutaminase (anti-t-TG Ab) and/or anti-endomysial antibodies (EMA). The pooled prevalence of biopsy proven CD in Asia-Pacific among high and low risk groups was 4.3% (95% CI 3.3-5.5%) and 0.61% (95% CI 0.4-0.8%) in 10,719 and 70,344 subjects, respectively. In addition, the pooled sero-prevalence and prevalence of CD in general population was significantly higher in children compared with adults and it was significantly greater in female vs. male (P < 0.05). Our results suggest high risk individuals of CD are key group that should be specifically targeted for prevention and control measures, and screening may prove to have an optimal cost-benefit ratio.

Persistent Iron Deficiency Anemia in Patients with Celiac Disease Despite a Gluten-Free Diet

Celiac disease (CD) is an autoimmune disorder characterized by intolerance to dietary gluten in genetically predisposed subjects. Iron deficiency anemia (IDA) is a common sign in CD, being the only abnormality in approximately 40% of celiac patients. A multifactorial etiology leads to IDA in CD. The two main causes are the villous atrophy of the mucosa at the site of iron absorption (the duodenum) and the resulting inflammation, which triggers the mechanism that leads to the anemia of chronic disease. Until now, it has been unclear why some patients with CD continue to have IDA despite a careful gluten-free diet (GFD) and the normalization of villous atrophy. Furthermore, some celiac patients are refractory to oral iron supplementation despite the healing of the mucosa, and they thus require periodic intravenous iron administration. The Marsh classification evaluates the degree of inflammation and villous atrophy, but it does not assess the possible persistence of ultrastructural and molecular alterations in enterocytes. The latter was found in CD in remission after adopting a GFD and could be responsible for the persistently reduced absorption of iron and IDA. Even in non-celiac gluten sensitivity, anemia is present in 18.5-22% of patients and appears to be related to ultrastructural and molecular alterations in intestinal microvilli. It is possible that a genetic component may also play a role in IDA. In this review, we evaluate and discuss the main mechanisms of IDA in CD and the possible causes of its persistence after adopting a GFD, as well as their therapeutic implications.

Correlation of TTG IgA Level with Small Intestinal Histopathological Changes for Celiac Disease among Adult Saudi Patients

Background and objectives

According to recent guidelines, a diagnosis of celiac disease (CD) can be made without a biopsy, especially in children. There are no enough studies despite high prevalence and differences in genetic, race, and cultures. Therefore, we examined the correlation between tissue transglutaminase (TTG) and duodenal biopsy changes in our region because we are identical and different from others in culture, environment, and habits, and the correlation is same as that in different regions.

Methods

A retrospective cohort study at the Ministry of National Guard Health Affaires (NGHA) health care facilities that are distributed throughout kingdom of Saudi Arabia from April 19, 2015, till March 29, 2018. This study used the BESTCARE system that includes data from all NGHA facilities; data from 513 patients with CD were collected. All patients diagnosed with celiac disease aged 15 years or more, confirmed by improvement on gluten-free diet (GFD), and were not on GFD before endoscopy or serology test or both of them were included in the study, and the TTG IgA level was measured at the same time or within 2–3 months of biopsy date. The exclusion criteria were negative duodenal biopsy, which is less than 2; patients with negative biopsy and negative serology; patients who were on GFD before testing, and any patients known to have immunity diseases or illness causing mucosal changes. The TTG IgA level was measured in IU/ mL and was labeled as negative (<20 IU/mL) and positive (≥ 20 IU/mL) based on the cutoff value. However, Intestinal biopsy findings were identified as Marsh classification groups.

Results

One hundred thirty-four patients who met the inclusion criteria were included in the study. Median age of our sample was 24 years (16–37 years). Among these, 99 (73.88%) were female patients, whereas male patients were only 35 (26.12%). Histopathologic investigation of intestinal biopsy were Marsh 0 group was 16 cases (11.9%), Marsh 1 group was 8 cases (6%), Marsh 2 group was 4 cases (3%), Marsh 3a group was 32 cases (23.9%), Marsh 3b group was 64 cases (47.8%), and Marsh 3c group was 10 cases (7.5%). The TTG IgA antibody serology groups were <20 IU/mL in 13 cases (9.7%) and ≥20 IU/mL in 121 cases (90.3%). Among all patients with CD who had negative biopsy (Marsh 0 group), 16 (100%) of them had positive TTG IgA antibody. However, among patients with Marsh 1 group biopsy, 5 (62.5%) cases had negative TTG IgA antibody compared with 3 (37.5%) positive cases. Of the four cases (100%) with Marsh 2 group, all of them had positive TTG IgA antibody. However, in Marsh 3a group biopsy, 3 (9.4%) cases had negative TTG IgA antibody compared with 29 (90.6%) cases with positive TTG IgA antibody. Furthermore, among the patients with Marsh 3b group biopsy, 5 (7.8%) had negative antibody and 59 (92.2%) had positive serology. Of all biopsies of Marsh 3c group, 10 (100 %) had positive TTG IgA antibody.

Conclusions

In perspective of high prevalence of CD in KSA, even more than western countries, we can pretend that positive TTG antibody tests can be applied for the diagnosis of CD without biopsy, particularly in symptomatic patients along with high titer, that is, 5–10 times the upper limit of normal (ULN). However, to validate it further, we need larger prospective studies in which duodenal biopsies should be taken according to recommended protocol and should be interpreted by experienced pathologist. Furthermore, biopsy is still needed in patients who do not show clinical improvement on a gluten-free diet and in cases with mildly or moderately elevated TTG IgA.

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.

Systematic review with meta-analysis: the prevalence of coeliac disease in patients with osteoporosis

BACKGROUND

Earlier studies have produced highly varying risk estimates for the prevalence of coeliac disease (CD) in osteoporosis.

AIMS

To investigate the prevalence of CD among individuals with osteoporosis.

METHODS

We conducted a systematic review of articles published in PubMed, Medline or EMBASE through May 2017 to identify studies looking at prevalence of CD in patients with osteoporosis. Search terms included "coeliac disease" combined with "fractures", "bone disease", "bone density", "densitometry", "osteoporos*", "osteomal*", "osteodys" or "dexa" or "dxa" or "skelet". Non-English papers with English-language abstracts were included. We used fixed-effects inverse variance-weighted models, and tested heterogeneity through subgroup analysis as well as through meta-regression.

RESULTS

We identified eight relevant studies, comprising data from 3188 individuals with osteoporosis. Of these, 59 individuals (1.9%) had CD. A weighted pooled analysis demonstrated biopsy-confirmed CD in 1.6% (95% CI = 1.1%-2.0%) of individuals with osteoporosis. The heterogeneity was moderate (I²  = 40.1%), and influenced by the underlying CD prevalence in the general population. After adding four studies (n = 814) with CD defined as positive tissue transglutaminase or endomysial antibodies, the pooled prevalence was comparable (1.6%; 95% CI = 1.2%-2.0%).

CONCLUSIONS

About 1 in 62 individuals with osteoporosis, or 1.6%, have biopsy-verified CD. This prevalence is comparable to that in the general population. These findings argue against routinely screening patients with osteoporosis for CD, which is contrary to current guideline recommendations. Additional studies are needed to determine the true utility of such screening programs.

Prevalence of Celiac Disease in Patients With Iron Deficiency Anemia-A Systematic Review With Meta-analysis

BACKGROUND & AIMS

Anemia is common in patients with celiac disease (CD) and a frequent mode of presentation. Guidelines recommend screening patients with iron-deficiency anemia (IDA) for CD. However, the reported prevalence of CD in patients with IDA varies. We performed a systematic review to determine the prevalence of biopsy-verified CD in patients with IDA.

METHODS

We performed a systematic review of articles published in PubMed Medline or EMBASE through July 2017 for the term "celiac disease" combined with "anemia" or "iron deficiency." We used fixed-effects inverse variance-weighted models to measure the pooled prevalence of CD. Meta-regression was used to assess subgroup heterogeneity.

RESULTS

We identified 18 studies composed of 2998 patients with IDA for inclusion in our analysis. Studies originated from the United Kingdom, United States, Italy, Turkey, Iran, and Israel. The crude unweighted prevalence of CD was 4.8% (n = 143). Using a weighted pooled analysis, we found a prevalence of biopsy-confirmed CD of 3.2% (95% confidence interval = 2.6-3.9) in patients with IDA. However, heterogeneity was high (I² = 67.7%). The prevalence of CD was not significantly higher in studies with a mean participant age older or younger than 18 years or in studies with a mixed-sex vs female-predominant (≥60%) population. On meta-regression, year of publication, female proportion, age at CD testing, and prevalence in the general population were not associated with the prevalence of CD in patients with IDA. In the 8 studies fulfilling all our quality criteria, the pooled prevalence of CD was 5.5% (95% confidence interval = 4.1-6.9).

CONCLUSIONS

In a systematic review and meta-analysis, we found that approximately 1 in 31 patients with IDA have histologic evidence of CD. This prevalence value justifies the practice of testing patients with IDA for CD.

Gluten sensitivities and the allergist: Threshing the grain from the husks

"Gluten sensitivity" has become commonplace among the public. Wheat allergy (WA) and celiac disease (CD) are well-defined entities, but are becoming a fraction of individuals following a gluten-free diet (GFD). Wheat allergy has a prevalence of <0.5%. Wheat, specifically its omega-5 gliadin fraction, is the most common allergen implicated in food-dependent, exercise-induced anaphylaxis. CD is a non-IgE hypersensitivity to certain cereal proteins: gluten in wheat, secalin in rye, hordein in barley, and to a lesser extent avenin in oat. It is a rare disease, with an estimated prevalence that varied widely geographically, being higher in Northern Europe and the African Saharawi region than in South-East Asia. In addition to suggestive symptoms, serologic testing has high diagnostic reliability and biopsy is a confirmatory procedure. Patients with CD have extra-intestinal autoimmune comorbid conditions more frequently than expected. A third entity is nonceliac gluten sensitivity, which has been created because of the increasing number of subjects who claim a better quality of life or improvement of their variety of symptoms on switching to a GFD. The phenomenon is being fueled by the media and exploited by the industry. The lack of a specific objective test has been raising substantial controversy about this entity. Allergists and gastroenterologists need to pay attention to the multitudes of individuals who elect to follow a GFD. Many such subjects might have WA, CD, or another illness. Providing them with appropriate evaluation and specific management would be of great advantages, medically and economically.

Global Prevalence of Celiac Disease: Systematic Review and Meta-analysis

BACKGROUND & AIMS

Celiac disease is a major public health problem worldwide. Although initially it was reported from countries with predominant Caucasian populations, it now has been reported from other parts of the world. The exact global prevalence of celiac disease is not known. We conducted a systematic review and meta-analysis to estimate the global prevalence of celiac disease.

METHODS

We searched Medline, PubMed, and EMBASE for the keywords celiac disease, celiac, celiac disease, tissue transglutaminase antibody, anti-endomysium antibody, endomysial antibody, and prevalence for studies published from January 1991 through March 2016. Each article was cross-referenced with the words Asia, Europe, Africa, South America, North America, and Australia. The diagnosis of celiac disease was based on European Society of Pediatric Gastroenterology, Hepatology, and Nutrition guidelines. Of 3843 articles, 96 articles were included in the final analysis.

RESULTS

The pooled global prevalence of celiac disease was 1.4% (95% confidence interval, 1.1%-1.7%) in 275,818 individuals, based on positive results from tests for anti-tissue transglutaminase and/or anti-endomysial antibodies (called seroprevalence). The pooled global prevalence of biopsy-confirmed celiac disease was 0.7% (95% confidence interval, 0.5%-0.9%) in 138,792 individuals. The prevalence values for celiac disease were 0.4% in South America, 0.5% in Africa and North America, 0.6% in Asia, and 0.8% in Europe and Oceania; the prevalence was higher in female vs male individuals (0.6% vs 0.4%; P < .001). The prevalence of celiac disease was significantly greater in children than adults (0.9% vs 0.5%; P < .001).

CONCLUSIONS

In a systematic review and meta-analysis, we found celiac disease to be reported worldwide. The prevalence of celiac disease based on serologic test results is 1.4% and based on biopsy results is 0.7%. The prevalence of celiac disease varies with sex, age, and location. There is a need for population-based prevalence studies in many countries.

Understanding Celiac Disease From Genetics to the Future Diagnostic Strategies

Celiac disease (CD) is an autoimmune disorder characterized by the permanent inflammation of the small bowel, triggered by the ingestion of gluten. It is associated with a number of symptoms, the most common being gastrointestinal. The prevalence of this illness worldwide is 1%. One of the main problems of CD is its difficulty to be diagnosed due to the various presentations of the disease. Besides, in many cases, CD is asymptomatic. Celiac disease is a multifactorial disease, HLA-DQ2 and HLA-DQ8 haplotypes are predisposition factors. Nowadays, molecular markers are being studied as diagnostic tools. In this review, we explore CD from its basic concept, manifestations, types, current and future methods of diagnosis, and associated disorders. Before addressing the therapeutic approaches, we also provide a brief overview of CD genetics and treatment.

Celiac disease in Iran: a systematic review and meta-analysis

Introduction

Celiac disease (CD) is a chronic autoimmune-mediated disorder with both intestinal and systemic manifestations. The aim of this study was to determine the prevalence of celiac disease in Iran.

Methods

We conducted a systematic search on Embase, Pub Med, Web of Science, Google Scholar, MagIran, Scientific Information database (SID) and Iranmedex from 2003 through to November 2015. The Der-Simonian/Laird’s (DL), with a 95% confidence interval employed to estimate the overall pooled prevalence. Heterogeneity was investigated by using subgroup analysis based on sample size and time of study.

Results

Sixty-three studies with 36,833 participants met inclusion criteria for analysis. The overall prevalence of celiac disease in 63 studies that had used serological tests for the diagnosis was observed as 3% (95% CI: 0.03–0.03) and the overall prevalence of celiac disease in studies that had used biopsy method for diagnosis was observed as 2% (95% CI: 0.01–0.02).

Conclusion

The prevalence of celiac disease in Iran was similar or even higher than world-wide reported.

Adult Celiac Disease: Patients Are Shorter Compared with Their Peers in the General Population

BACKGROUND Delay in diagnosis of celiac disease (CD) occurs frequently, although its consequences are mostly not known. One of the presented symptoms in pediatric patients with CD is the short stature. However, far too little attention has been paid to physical features including height of adult patients with CD. This study was undertaken to evaluate whether patients suffering from CD are shorter in comparison with the general population without CD. As well, we evaluated probable correlations between demographic and physical features, main complains, serum anti tTG level, and intestinal pathology damage between short (lower quartile) versus tall stature (upper quartile) patients with CD. METHODS This was a retrospective cross-sectional study on 219 adult patients diagnosed as having CD in the Celiac Disease Center, between June 2008 and June 2014 in Mashhad, Iran. The exclusion criteria were ages less than 18 and more than 60 years. Height was compared with a group of 657 age- and sex matched control cases from the healthy population. The probable influencing factors on height such as intestinal pathology, serum level of anti-tissue transglutaminase(anti-tTG), serum vitamin D, and hemoglobin level at the time of diagnosis were assessed and were compared in short (lower quartile) versus tall stature (upper quartile) patients with CD. RESULTS Both male (n=65) and female (n=154) patients with CD were shorter than their counterpart in the general population (males: 168.5±8.6 to 171.3±7.2cm, p <0.01 and females: 154.8±10.58 to 157.8±7.2 cm, p <0.01). Spearman linear correlation showed height in patient with CD was correlated with serum hemoglobin (p <0.001, r=0.285) and bone mineral density (p<0.001) and not with serum vitamin D levels (p =0.024, r=0.237), but was not correlated with anti-tTG serum levels (p=0.97). CD patients with upper and lower quartile of height in men and women had no significant difference in the anti-tTG level and degree of duodenal pathology(Marsh grade). Anemia as main complaint was more prevalent in shorter versus taller men. CONCLUSION Adults with CD are shorter compared with healthy adults. There is a direct correlation between height and anemia and bone mineral density. This finding highlights the importance of early detection and treatment of CD.

Dietary compliance in Iranian children and adolescents with celiac disease

INTRODUCTION

Celiac disease (CD) is caused due to intake of gluten, a protein component in wheat, barley, and rye. The only treatment currently available for CD is strict lifetime adherence to a gluten-free diet (GFD) which is a diet that excludes wheat, barley, and rye. There is limited information on barriers to following a GFD. The present study aimed to investigate the compliance with a GFD, barriers to compliance, and the impact of compliance on the quality of life (QOL) in Iranian children and adolescents suffering from CD.

METHODS

In this cross-sectional study, a total of 65 known cases of CD (both males and females), diagnosed in Namazi Hospital, a large referral center in south of Iran, selected by census were studied in 2014. Dietary compliance was assessed using a questionnaire. A disease-specific QOL questionnaire for children with CD (the celiac disease DUX [CDDUX]) was used. Comparisons between categorical variables were performed using chi-square test.

RESULTS

Sixty-five patients, 38 females (58.5%) and 27 (41.5%) males, were surveyed. Mean (± standard deviation [SD]) age of the respondents was 11.3 (±3.8) years. Dietary compliance was reported by 35 (53.8%) patients. The mean (± SD) CDDUX score was higher in dietary-compliant patients (33.5 [±19.4] vs 26.7 [±13.6], respectively, P=0.23). The score of CDDUX in parents of patients in dietary-compliant group was more than the noncompliant patients (28.1 [±13.5] vs 22.1 [±14], respectively, P=0.1). Barriers to noncompliance were poor or unavailability (100%), high cost (96.9%), insufficient labeling (84.6%), poor palatability (76.9%), and no information (69.23%).

CONCLUSION

Approximately half of the patients with CD reported dietary compliance. Poor or unavailability was found to be the most important barrier contributing to noncompliance. The QOL was better in compliant patients. Proposed strategies to improve compliance are greater availability of gluten-free products, better food labeling, and better education about the diet and condition.

THE PREVALENCE OF CELIAC DISEASE IN PATIENTS WITH IRON-DEFICIENCY ANEMIA IN CENTER AND SOUTH AREA OF IRAN

BACKGROUND

Celiac disease is an immune-mediated enteropathy due to a permanent sensitivity to gluten in genetically susceptible people. Iron-deficiency anemia is the most widely experienced anemia in humans. Iron-deficiency anemia additionally is a common extra intestinal manifestation of celiac disease.

OBJECTIVE

To investigate correlation between tTg levels and histological alterations and then to determine the prevalence of celiac disease in Center and South area patients of Iran with iron deficiency anemia.

METHODS

A total of 402 patients aged 12-78 years who presented with iron-deficiency anemia were included in this study. Hemoglobin, mean corpuscular volume and serum ferritin were determined. Venous blood samples for anti-tissue transglutaminase antibody immunoglobuline A and G were obtained from these patients. Upper gastrointestinal endoscopy was recommended to patients who had positive serology.

RESULTS

Of 402 patients with iron-deficiency anemia, 42 (10.4%) had positive serology for celiac disease. The small intestine biopsy of all patients with positive serology showed pathological changes (Marsh I, II & III). There was not significant difference in the mean hemoglobin level between iron-deficiency anemia patients with celiac disease and without celiac disease, duodenal biopsy results did not show significant relationship between the severity of pathological changes and levels of anti-tTG IgG (P -value: 0/869) but significant relationship was discovered between pathological changes and levels of anti-tTG IgA (P -value: 0/004).

CONCLUSION

Screening of celiac disease by anti-tissue transglutaminase antibody should be completed as a routine investigation in patients with iron-deficiency anemia. Also physicians must consider celiac disease as a possible reason of anemia in all patients with iron deficiency anemia.

Prevalence of Celiac Disease in Patients with Autoimmune Thyroid Disease: A Meta-Analysis

BACKGROUND

Several screening studies have indicated an increased prevalence of celiac disease (CD) among individuals with autoimmune thyroid disease (ATD), but estimates have varied substantially.

OBJECTIVE

The aim of this study was to examine the prevalence of CD in patients with ATD.

METHOD

A systematic review was conducted of articles published in PubMed Medline or EMBASE until September 2015. Non-English papers with English-language abstracts were also included, as were research abstracts without full text available when relevant data were included in the abstract. Search terms included "celiac disease" combined with "hypothyroidism" or "hyperthyroidism" or "thyroid disease." Fixed-effects inverse variance-weighted models were used. Meta-regression was used to examine heterogeneity in subgroups.

RESULTS

A pooled analysis, based on 6024 ATD patients, found a prevalence of biopsy-confirmed CD of 1.6% [confidence interval (CI) 1.3-1.9%]. Heterogeneity was large (I(2) = 70.7%). The prevalence was higher in children with ATD (6.2% [CI 4.0-8.4%]) than it was in adults (2.7%) or in studies examining both adults and children (1.0%). CD was also more prevalent in hyperthyroidism (2.6% [CI 0.7-4.4%]) than it was in hypothyroidism (1.4% [CI 1.0-1.9%]).

CONCLUSIONS

About 1/62 patients with ATD have biopsy-verified CD. It is argued that patients with ATD should be screened for CD, given this increased prevalence.

Prevalence of celiac disease in Asia: A systematic review and meta-analysis

BACKGROUND AND AIM

Celiac disease (CD) is emerging in Asia. While a few population-based studies from Asia have reported a prevalence of CD from 0.1% to 1.3%, the exact prevalence of CD in Asia is not known. We conducted a systematic review and meta-analysis to estimate the prevalence of CD in Asia.

METHODS

On search of literature, we found 1213 articles, of which 18 articles were included. Diagnosis of CD was based on European Society of Pediatric Gastroenterology, Hepatology and Nutrition guidelines.

RESULTS

Pooled sero-prevalence of CD in Asia was 1.6% in 47 873 individuals based on positive anti-tissue transglutaminase and/or anti-endomysial antibodies. Pooled prevalence of biopsy proven CD in Asia was 0.5% in 43 955 individuals. The prevalence of CD among women was higher than in men (0.5% vs 0.4%, P = 0.04). The pooled prevalence of CD was 0.3% in Iran, 0.5% in Turkey, 0.6% in India, and 0.7% in Israel. The pooled prevalence of CD was significantly higher in Israel and India as compared with that in Iran.

CONCLUSIONS

Celiac disease is not uncommon in Asia, and the sero-prevalence and prevalence of CD in Asia are 1.6% and 0.5%, respectively. The prevalence of CD varies with gender and geographic location. There is a need for population-based prevalence studies in many Asian countries to properly estimate the burden of CD in Asia.

Coeliac disease as a potential cause of idiopathic portal hypertension: a case report

Idiopathic portal hypertension is a disorder that has various clinical features. It is mostly characterized by bleeding oesophageal varices, obvious splenomegaly, anaemia and, occasionally, jaundice and ascites. Here we described an interesting case of idiopathic portal hypertension caused by coeliac disease in a 38-year-old woman. By putting this patient on a gluten-free diet, liver function tests became normal and portal vein diameter returned to normal range. This report indicates that, in coeliac disease, repetitive stimulation by antigens along the portal vein-and immune responses to them-can result in the development of idiopathic portal hypertension.

Celiac Disease in Women With Infertility: A Meta-Analysis

BACKGROUND

Celiac disease (CeD) is a systemic disease with manifestations not limited to small intestine. The data on association between CeD and infertility is contradictory. There are no recommendations for the screening of female patients with infertility for CeD.

AIM

We conducted a meta-analysis to find out whether women with infertility are at higher risk of CeD.

METHODS

Literature search was performed using the MeSH keywords "CeD," "gluten," and "infertility." Diagnosis of CeD was based on positive serology and biopsies showing villous atrophy. Data were extracted about CeD patients in 3 groups-women with infertility (including unexplained infertility), unexplained infertility, and controls. Pooled odds ratio (OR) and prevalence, with 95% confidence intervals (CI), were calculated.

RESULTS

Of 105 relevant studies, 5 studies were included for calculation of pooled OR. Four additional studies, where data on controls were not available, were also considered for calculation of pooled prevalence of CeD. Women with infertility had 3.5 times higher odds of having CeD in comparison with control population (OR=3.5; 95% CI, 1.3-9; P<0.01). Similarly, women with "unexplained infertility" had 6 times higher odds of having CeD than controls (OR=6; 95% CI, 2.4-14.6). Of 884 women with infertility, 20 had CeD indicating a pooled prevalence of 2.3% (95% CI, 1.4-3.5). Of 623 women with "unexplained infertility," 20 had CeD. The pooled prevalence of CeD in women with unexplained infertility was 3.2 (95% CI, 2-4.9).

CONCLUSIONS

CeD is more prevalent in women with "all-cause" infertility and "unexplained" infertility than that in general population.

DQ2, DQ7 and DQ8 Distribution and Clinical Manifestations in Celiac Cases and Their First-Degree Relatives

HLA-linked genes are relevant to celiac disease (CD); the potential genetic differences present worldwide are not fully understood. Previous results suggest that the distribution of HLA-DQ2/DQ7/DQ8 in Chile may differ from that in Europe and North America. In celiac patients and their first-degree relatives (FDRS), we assessed their clinical, serological and histological characteristics, determined HLA-DQ2, HLA-DQ7 and HLA-DQ8 alleles and genotypes, and evaluated the relations between them. A total of 222 individuals were assessed (56 cases, 166 FDRs). 16.9% of FDRs were tTG positive; 53.6% of them showed overweight/obesity and 3% undernourishment; they spontaneously declared being asymptomatic, but detailed questioning revealed that 60.7% experienced symptoms, which had not been investigated. DQ2 was present in 53.9% and 43.9.0% of cases and FDRs (p < 0.05). The most frequent genotype distribution was DQ2/DQ7 (fr 0.392 (cases) and 0.248 (FDRs), respectively, p < 0.02). The next most common genotypes were HLA-DQ2/DQ8 (fr 0.236 in FDRs and 0.176 in cases, p < 0.05). 3.92% cases were not HLA-DQ2/DQ8 carriers. Among tTG positive FDRs, 57.4%, 22.3% and 20.2% carried DQ2, DQ7 and DQ8, respectively. In cases, 72.7% of the biopsies classified Marsh ≥ 3 carried at least one DQ2; 91.7% of DQ2/DQ2 and 88.3% of DQ2/DQ7 were Marsh ≥ 3. Thus, DQ2 frequency is lower than reported; the higher frequency found for DQ8 and DQ7 concur with recent publications from Argentine and Brazil. These results suggest that although CD may manifest clinically in ways similar to those described in other populations, some genetic peculiarities in this region deserve further study.

Celiac disease from a global perspective

Celiac disease (CD) is one of the commonest lifelong disorders in countries populated by individuals of European origin, affecting approximately 1% of the general population. This is a common disease also in North Africa, Middle East and India. The widespread diffusion of CD is not surprising given that its causal factors (HLA predisposing genotypes and consumption of gluten-containing cereals) show a worldwide distribution. Further studies are needed to quantify the incidence of CD in apparently "celiac-free" areas such as Sub-Saharan Africa and Far East. Several reports have shown that CD is increasing in frequency in different geographic areas. Genetic factors do not explain the rising incidence during the last decades; environmental or lifestyle factors may be responsible for these changes over time. The majority of patients with CD are still undiagnosed all over the world, leading to debate about the need of screening program.

Titers of anti-tissue transglutaminase antibody correlate well with severity of villous abnormalities in celiac disease

GOALS

We reviewed our celiac disease (CeD) database to study if anti-tissue transglutaminase (tTG) antibody (ab) titers correlate with severity of villous abnormalities in Indian patients and to find out a cutoff value of anti-tTG ab fold-rise, which could best predict CeD.

BACKGROUND

Guidelines for diagnosing CeD suggest that biopsy could be avoided in some patients with high anti-tTG ab titer.

STUDY

We reviewed a cohort of 366 anti-tTG ab-positive individuals in whom duodenal biopsies were performed. Anti-tTG ab was obtained before initiation of gluten-free diet. Anti-tTG ab results were expressed in terms of fold-rise by calculating ratio of observed values with cutoff value. CeD was diagnosed if in addition to positive serology, patients had villous atrophy (>Marsh grade 2) and unequivocal response to gluten-free diet.

RESULTS

The mean anti-tTG fold-rise in groups with Marsh grade ≤2 was 2.6 (±2.5), grade 3a was 4.0 (±3.9), 3b was 5.7 (±5.1), and 3c was 11.8 (±8.0). The positive likelihood ratio for diagnosing CeD was 15.4 and 27.4 at 12- and 14-fold-rise of anti-tTG ab titer, respectively. The positive predictive value of diagnosis of CeD was 100% when anti-tTG ab titer was 14-fold higher over the cutoff value. Fifty-seven (43.9%) individuals with anti-tTG titer rise <2-fold high also had CeD.

CONCLUSIONS

As severity of villous abnormality increases, titer of anti-tTG also rises. Presence of villous atrophy can be predicted at very high anti-tTG ab titer. In contrast to emerging belief, mucosal biopsies should be performed even if anti-tTG ab titer is <2 times, because many patients with CeD have low titers.

Serologic screening of celiac disease in adolescents

OBJECTIVE

This study aimed to identify the seroprevalence of celiac disease in adolescents from public schools in the city of Salvador, Bahia.

METHODS

This was a cross-sectional study with probabilistic sample of 1,213 adolescents, aged 11 to 17 years old, of both genders. The body mass index was used to determine the participants' nutritional status based on the percentiles for age and gender recommended by the World Health Organization. Measurement of the anti-human transglutaminase immunoglobulin A (anti-tTG-IgA) antibody was established as the specific screening test for celiac disease, which involved an enzyme-linked immunosorbent assay (ELISA). Descriptive analysis was performed using proportions and means (standard deviation).

RESULTS

The female gender prevailed in the sample, and most of the participants had normal weights. The anti-tTG-IgA antibody was positive in 6/1,213 (0.49%) adolescents.

CONCLUSION

The seroprevalence of celiac disease was 0.49% in the investigated adolescents. Further studies are necessary to establish the prevalence of celiac disease in this age range.

Celiac disease prevalence in the patients with irritable bowel syndrome in the ilam province; a cross sectional study from Western iran

INTRODUCTION

Many studies have shown that the prevalence of celiac disease (CD) is increasing in the patients with irritable bowel syndrome (IBS), but the present evidences are controversy and all of the researches don't suggest evaluation of the patients with IBS for the CD.

MATERIALS AND METHODS

In the cross-sectional study, 1000 patients that affected by IBS with the predominant feature of diarrhea who referred to the gastroenterology clinic were evaluated during 2009-2012 years. Blood samples were taken from the patients for ELISA of IgA tissue transglutaminase (TTG) Ab. Then biopsy was taken from the second part of duodenum of all of patients by endoscopy and the sample was referred to pathologist for histopathology evaluation in order to confirm diagnosis.

RESULTS

About half of the patients with IBS were women (50.3%) and the mean age ± Standard deviation of the men and women was 29.59±11.41 and 28.42±11.73, respectively. The mean titer of TTG IgA Ab in the women and men affected by IBS was 5.25±17.77 and 7.22±25.4, respectively. Seventy six cases (7.6%) that affected by IBS had high serum level of Ab titer (TTG IgA.Ab≥10) that including 41 women and 35 men. In the patients with high serum level of Ab titer, 57 cases (75%) were affected by celiac disease (based on histopathology report). Therefore, the prevalence of CD was 5.7% among patients with IBS.

CONCLUSION

In the current study the incidence of CD was evaluated 5.7 cases per each 100 people with IBS. It's suggested that all of the patients with diarrhea predominant IBS and high serum level of TTG IgA Ab must be examined for evaluation of CD.

Co-localization of gluten consumption and HLA-DQ2 and -DQ8 genotypes, a clue to the history of celiac disease

Celiac disease is an immune-mediated disorder triggered by gluten in genetically susceptible persons. Despite its detrimental effects on human health, it has not disappeared over time. The current evolutionary theory is that celiac disease is more common in areas reached later by agricultural revolution than in countries that started consumption of wheat earlier, due to negative selection caused by celiac disease. We reviewed data on worldwide prevalence of celiac disease, wheat consumption, and frequencies of HLA-celiac-disease-predisposing-genotypes to investigate their mutual relationship. Studies assessing prevalence of celiac disease were identified through a MEDLINE search. Wheat consumption and frequencies of HLA-DQ2-DQ8 were obtained from Food and Agriculture Organization of the United Nations and allelefrequencies.net database. Correlations between celiac disease, wheat consumption, and HLA were analyzed by linear regression. We observed a significant correlation between wheat consumption and HLA DQ2 (p=0.01) and the sum of DQ2 and DQ8 (p=0.01) frequencies. Wheat consumption and HLA-DQ2 tend to co-localize in different continents. The correlation between the prevalence of celiac disease and either DQ2 and/or DQ8, or the product of DQ2+DQ8*wheat consumption was not statistically significant. Co-localization of gluten consumption and HLA-celiac-disease-predisposing-genotypes can be explained by positive selection of HLA-DQ2 genes in wheat-consuming areas, and "demic diffusion" of Middle East farmers into Europe.

Evaluation of European coeliac disease risk variants in a north Indian population

Studies in European populations have contributed to a better understanding of the genetics of complex diseases, for example, in coeliac disease (CeD), studies of over 23 000 European samples have reported association to the HLA locus and another 39 loci. However, these associations have not been evaluated in detail in other ethnicities. We sought to better understand how disease-associated loci that have been mapped in Europeans translate to a disease risk for a population with a different ethnic background. We therefore performed a validation of European risk loci for CeD in 497 cases and 736 controls of north Indian origin. Using a dense-genotyping platform (Immunochip), we confirmed the strong association to the HLA region (rs2854275, P=8.2 × 10⁻⁴⁹). Three loci showed suggestive association (rs4948256, P=9.3 × 10⁻⁷, rs4758538, P=8.6 × 10⁻⁵ and rs17080877, P=2.7 × 10⁻⁵). We directly replicated five previously reported European variants (P<0.05; mapping to loci harbouring FASLG/TNFSF18, SCHIP1/IL12A, PFKFB3/PRKCQ, ZMIZ1 and ICOSLG). Using a transferability test, we further confirmed association at PFKFB3/PRKCQ (rs2387397, P=2.8 × 10⁻⁴) and PTPRK/THEMIS (rs55743914, P=3.4 × 10⁻⁴). The north Indian population has a higher degree of consanguinity than Europeans and we therefore explored the role of recessively acting variants, which replicated the HLA locus (rs9271850, P=3.7 × 10⁻²³) and suggested a role of additional four loci. To our knowledge, this is the first replication study of CeD variants in a non-European population.

Celiac disease: a disease with varied manifestations in adults and adolescents

OBJECTIVE

We aimed to determine the characteristics of patients with celiac disease and differences between those who presented during adolescence or adulthood.

METHODS

We retrospectively reviewed the case records of 233 consecutive patients with celiac disease who were diagnosed at 12-18 years or >18 years of age. The diagnosis of celiac disease was made on the basis of the modified European Society of Pediatric Gastroenterology, Hepatology and Nutrition criteria.

RESULTS

The diagnosis of celiac disease was made after 18 years of age in 153 (65.7%) patients. Median duration of symptoms at the diagnosis was 54 months (range 1 month to 29 years). In all, 103 (44.2%) patients with atypical manifestations were referred by other departments for evaluation. Chronic diarrhea (48.5%), short stature (27.0%) and chronic anemia (9.0%) were the common modes of presentation. Elevated level of aminotransaminase were present in 50 (24.3%) patients. Chronic diarrhea, hypocalcemia and hypoalbuminemia were present in significantly higher number of adult than adolescent patients. In all, 227 (97.4%) patients responded to a 6-month gluten-free diet and six non-responders were non-compliant.

CONCLUSIONS

More than 40% of the patients with celiac disease present to clinicians other than gastroenterologists or internists with atypical manifestations. A high index of suspicion is required for diagnosing its variant forms.

Systematic review: worldwide variation in the frequency of coeliac disease and changes over time

BACKGROUND

Coeliac disease (CD), originally thought to be largely confined to Northern Europe and Australasia and uncommon in North America and the Middle East, is now recognised to be equally common in all these countries. It is still thought to be rare in the Orient and Sub-Saharan Africa.

AIM

To assess geographical differences and time trends in the frequency of CD.

METHODS

Medline and Embase searches were conducted on 10 November 2012, from 1946 and 1980 respectively, using the key words: coeliac disease or celiac disease + prevalence or incidence or frequency.

RESULTS

There were significant intra- and inter-country differences in the prevalence and incidence of CD. Only 24 ethnic Chinese and Japanese patients have been reported in the English literature. Of CD-associated HLA DQ antigens, DQ2 occurs in 5-10% of Chinese and sub-Saharan Africans, compared to 5-20% in Western Europe. DQ8 occurs in 5-10% of English, Tunisians and Iranians, but in <5% of Eastern Europeans, Americans and Asians. The prevalence and incidence of both clinically and serologically diagnosed CD increased in recent years. These geographical and temporal differences seem genuine, although variable indices of suspicion and availability of diagnostic facilities are confounding factors.

CONCLUSIONS

Coeliac disease is increasing in frequency, with significant geographical differences. Although few cases have been described to date in the Orient and Sub-Saharan Africa, there is a significant prevalence of HLA DQ2 and wheat consumption is of the same order as that in Western Europe. CD may therefore become more common in the future in these countries.

Prevalence of celiac disease in Germany: A prospective follow-up study

AIM: To determine the prevalence of celiac disease in a randomly selected population sample.

METHODS: A total of 2157 subjects (1036 males; 1121 females) participating in a population-based cross-sectional study underwent laboratory testing for tissue transglutaminase and antibodies to immunoglobulin A, endomysium and antigliadin. In a second step, all subjects who had been examined serologically were surveyed using a questionnaire that included questions specific to celiac disease. Subjects with positive antibody titers and those with histories positive for celiac disease then underwent biopsy. At the first follow up, antibody titers were again determined in these subjects and subjects were questioned regarding symptoms specific for celiac disease and disorders associated with celiac disease. The second follow up consisted of a telephone interview with subjects positive for celiac disease.

RESULTS: Antibody tests consistent with celiac disease were reported in eight subjects, corresponding to an overall prevalence of 1:270 (8/2157). The prevalence among women was 1:224 and 1:518 in men. Classical symptoms were observed in 62.5% of subjects. Atypical celiac disease was present in 25.0%, and transient celiac disease in 12.5%. False-negative test results were returned in three subjects. This yields a sensitivity and specificity of 62.5% and 50.0%, respectively, for tissue transglutaminase immunoglobulin-A antibody; of 62.5% and 71.4% respectively, for endomysium antibody; and of 62.5% and 71.4%, respectively, for antigliadin antibody.

CONCLUSION: The prevalence rate in our collective lies within the middle tertile of comparable studies in Europe. The use of a single antibody test for screening purposes must be called into question.

Seroprevalence of celiac disease among healthy adolescents in Saudi Arabia

AIM: To identify the seroprevalence of celiac disease among healthy Saudi adolescents.

METHODS: Between December 2007 and January 2008, healthy students from the 10^th to 12^th grades were randomly selected from three regions in Saudi Arabia. These regions included the following: (1) Aseer region, with a student population of 25512; (2) Madinah, with a student population of 23852; and (3) Al-Qaseem, with a student population of 16067. Demographic data were recorded, and a venous blood sample (5-10 mL) was taken from each student. The blood samples were tested for immunoglobulin A and immunoglobulin G endomysial antibodies (EMA) by indirect immunofluorescence.

RESULTS: In total, 1167 students (614 males and 553 females) from these three regions were randomly selected. The majority of the study population was classified as lower middle class (82.7%). There were 26 (2.2%) students who had a positive anti-EMA test, including 17 females (3.1%) and 9 males (1.5%). Al-Qaseem region had the highest celiac disease prevalence among the three studied regions in Saudi Arabia (3.1%). The prevalence by region was as follows: Aseer 2.1% (10/479), Madinah 1.8% (8/436), and Al-Qaseem 3.2% (8/252). The prevalence in Madinah was significantly lower than the prevalence in Aseer and Al-Qaseem (P = 0.02).

CONCLUSION: Our data suggest celiac disease prevalence might be one of the highest in the world. Further studies are needed to determine the real prevalence.

Prevalence of celiac disease in healthy Iranian school children

BACKGROUND AND OBJECTIVES

Other than its classic presentation, celiac disease can be completely asymptomatic in a proportion of the general population. Subjects with silent celiac disease are at risk of potential complications of the disease, which indicates the importance of early diagnosis. In this study we investigated the prevalence of silent celiac disease in healthy children in our area.

DESIGN AND SETTING

Cross-sectional screening of healthy children in Shiraz city.

SUBJECTS AND METHODS

Fifteen hundred school children, 6 to 12 years of age in Shiraz (Southern Iran) were screened for celiac disease through serological testing of their serum anti-tissue transglutaminase immunoglobulin A antibodies. A small intestinal biopsy was performed for children with positive serology tests and pathologic reports were given according to the modified Marsh criteria.

RESULTS

Of the total students included, with a mean (SD) age of 9.5 (1.3) years, 30 subjects had positive anti-tissue transglutaminase immunoglobulin A antibodies, resulting in a total seropositivity of 2%. The prevalence of biopsy proven celiac disease (silent celiac) was 0.6%.

CONCLUSION

As in many other regions worldwide, this study estimated a relatively high prevalence of silent celiac disease in children in our area, citing the disease as an important health problem in our region.

Celiac disease in the developing world

The prevalence of celiac disease (CD) in many developing countries is similar to that of developed areas, in both low- and high-risk groups. The disorder is underestimated because of lack of disease awareness. CD is strongly associated with HLA-DQ2 in developing countries. Clinical presentation may be characterized by chronic diarrhea, anemia, stunting and increased mortality. Few studies have addressed atypical or silent CD. Diagnosis is initially made by serologic tests and is confirmed by small intestinal biopsies. In developing countries the adherence to the treatment is still difficult because of poor availability of dedicated gluten-free food.

Triagem sorológica para doença celíaca em adolescentes e adultos jovens, estudantes universitários

OBJETIVOS: avaliar a positividade sorológica para doença celíaca em um grupo de adolescentes e adultos jovens da cidade do Recife, Nordeste do Brasil. MÉTODOS: a amostra foi composta por estudantes matriculados nos cursos de graduação do Centro de Ciências da Saúde da Universidade Federal de Pernambuco. Os estudantes foram submetidos à coleta de sangue para pesquisa sorológica do anticorpo antitransglutaminase tecidual humana e responderam a questionário sobre sintomas e condições mórbidas associadas à doença celíaca. O anticorpo antitrans-glutaminase foi pesquisado por técnica de Elisa, considerando-se positivos valores acima de 10 U/mL, conforme estabelecido pelo fabricante. Nos pacientes que tiveram sorologia positiva para o anticorpo antitransglutaminase realizou-se a sorologia para o anticorpo antiendomíseo, por imunofluorescência indireta, utilizando kit comercialmente disponível. RESULTADOS: seiscentos e oitenta e três universitários participaram da pesquisa. Os estudantes tinham entre 18 e 30 anos e mediana de idade de 21 anos. O anticorpo antitransglutaminase foi positivo em 12/683, soroprevalência de 1,76% (IC95%: 0,95-3,13%). O anticorpo antiendomíseo foi realizado em 11 amostras e reagente em quatro. Oito estudantes com sorologia positiva tinham sintomas e/ou condições mórbidas associadas à doença celíaca. CONCLUSÕES: a elevada presença de anticorpos anti-transglutaminase encontrada neste estudo é semelhante a da Europa e Estados Unidos da América, sugere a possibilidade da triagem sorológica mesmo em populações consideradas de baixo risco.

Prevalence of coeliac disease in healthy blood donors: a study from north India

BACKGROUND

Blood donor screening can help predict prevalence of coeliac disease in population.

METHODS

Between December 2010 and June 2011, healthy blood donors were screened using anti-tissue glutaminase antibodies. Those positive underwent duodenoscopy. Their age, gender, body mass index and haemoglobin and histological changes were recorded.

RESULTS

Of the 1610 blood donors screened, 1581 (98.2%) were males. The mean age of donors was 31.51 ± 9.66 years and the mean body mass index was 22.12 ± 4.24 kg/m(2). Nine (0.56%) men were seropositive. Endoscopic features included reduced fold height (9), scalloping (8), grooving (7) and mosaic mucosal pattern (3). Eight had Marsh IIIa changes whilst one had IIIb change. The prevalence of coeliac disease was 1:179 (0.56%, 95% confidence interval 1/366-1/91, 0.27-1.1%). None of the 9 patients had any symptoms. Their mean haemoglobin and body-mass index was similar to rest of the cohort.

CONCLUSION

The prevalence of coeliac disease amongst apparently healthy blood donors was 1:179 (0.56%).

Timing of introduction of gluten and celiac disease risk

Breast milk is the natural nutrition for infants, but in the second half of the first year of life, complementary feeding is needed. Many complementary foods contain gluten, but gluten exposure is associated with the risk of developing celiac disease (CD). CD is a disease with considerable morbidity and mortality. Although CD is associated with certain genetic features, carrying the human leukocyte antigen haplotypes DQ2 or DQ8 (a prerequisite for CD development) cannot fully explain who will or who will not develop CD. Potential risk factors for CD include perinatal events and infant feeding practice. With the exception that children who are breastfed at and beyond gluten introduction into the diet probably may be at a lower risk of developing CD, and that heavy gluten load early in life may increase the risk of future CD, data on the impact of infant feeding are inconsistent.

Immunological comorbity in coeliac disease: associations, risk factors and clinical implications

PURPOSE

Coeliac disease is frequently associated with other immunomediated diseases. Our aim was to identify immunological comorbidities and possible risk factors for their development in coeliac patients.

METHODS

We recruited a cohort of 1,015 coeliac patients followed from 0 to 46 years in a single tertiary referral centre. Data were collected from the yearly scheduled clinical and serological evaluations. Possible risk factors such as demographic parameters, type of symptomatic presentation, gluten exposure, gluten-free diet compliance and family history were all evaluated. Subjects (848,606) from the regional health registry were investigated as controls.

RESULTS

The prevalence of immunomediated diseases was higher in patients with coeliac disease compared to the registry population (23 % vs 0.4 %, p < 0.001). Diagnosis during paediatric age represented a risk factor for the presence of at least an immunomediated disease (hazard ratio = 1.62, 95 % confidence interval 1.15-2.29, p = 0.0061). Type of presentation and dietetic compliance did not represent risk factors. Long-standing gluten exposure reduced the risk of developing immunomediated diseases in coeliac subjects (hazard ratio for 1 year longer exposure 0.23, 95 % confidence interval 0.16-0.33, p < 0.0001). A familiar background characterized by the presence of immunological disorders was not a risk factor, although 419 (13 %) first degree relatives of coeliac patients out of 3,195 had an immunomediated disease.

CONCLUSIONS

Our study suggests the need to investigate coeliac patients for other associated immunomediated diseases, independently of sex, gluten exposure and compliance to therapy; also subjects diagnosed in paediatric age should be carefully screened during follow up.

Coeliac disease in irritable bowel syndrome (Rome III) in Southeast Iran

BACKGROUND AND STUDY AIMS

Irritable bowel syndrome (IBS) is a common functional gastrointestinal (GI) disorder and coeliac disease (CD) is an auto-immune enteropathy that can mimic almost any functional GI disorder. Both IBS and coeliac disease share common symptoms. The aim of the present study was to estimate the prevalence of CD in patients with IBS and its sub-types.

PATIENTS AND METHODS

In this cross-sectional study (2008-2010), all consecutive patients with IBS who fulfilled the Rome III criteria attending the GI units in Zahedan (Southeast Iran) were included. Patients based on the sub-type of IBS were classified as diarrhoea-predominant irritable bowel syndrome (D-IBS), constipation-predominant irritable bowel syndrome (C-IBS) and alternating symptoms (mixed type). Immunoglobulin A (IgA) tissue transglutaminase (anti-tTG) was used to screen patients for CD. In the case of positive serologic test, duodenal biopsies were taken to confirm the diagnosis.

RESULTS

A total of 364 (221 females and 143 males) patients with IBS were included. The mean ± standard deviation (SD) age of patients was 37.4 ± 12.4 years. Twenty (5.5%) patients were found to have positive IgA anti-tTG. Main symptoms of patients were diarrhoea (11/20), bloating (10/20) and abdominal distension (6/20). Thirteen (10.5%) patients were found to have positive IgA anti-tTG among the D-IBS, two (1.6%) in the C-IBS and five (4.2%) in M-IBS groups.

CONCLUSION

The prevalence of CD in IBS is high. IBS subjects whose main complaint is diarrhoea, bloating or even abdominal distension should be evaluated for CD.

Burden of celiac disease in the Mediterranean area

AIM: To estimate the burden of undiagnosed celiac disease (CD) in the Mediterranean area in terms of morbidity, mortality and health cost.

METHODS: For statistics regarding the population of each country in the Mediterranean area, we accessed authoritative international sources (World Bank, World Health Organization and United Nations). The prevalence of CD was obtained for most countries from published reports. An overall prevalence rate of 1% cases/total population was finally estimated to represent the frequency of the disease in the area, since none of the available confidence intervals of the reported rates significantly excluded this rate. The distribution of symptoms and complications was obtained from reliable reports in the same cohort. A standardized mortality rate of 1.8 was obtained from recent reports. Crude health cost was estimated for the years between symptoms and diagnosis for adults and children, and was standardized for purchasing power parity to account for the different economic profiles amongst Mediterranean countries.

RESULTS: In the next 10 years, the Mediterranean area will have about half a billion inhabitants, of which 120 million will be children. The projected number of CD diagnoses in 2020 is 5 million cases (1 million celiac children), with a relative increase of 11% compared to 2010. Based on the 2010 rate, there will be about 550 000 symptomatic adults and about 240 000 sick children: 85% of the symptomatic patients will suffer from gastrointestinal complaints, 40% are likely to have anemia, 30% will likely have osteopenia, 20% of children will have short stature, and 10% will have abnormal liver enzymes. The estimated standardized medical costs for symptomatic celiac patients during the delay between symptom onset and diagnosis (mean 6 years for adults, 2 years for children) will be about €4 billion (€387 million for children) over the next 10 years. A delay in diagnosis is expected to increase mortality: about 600 000 celiac patients will die in the next 10 years, with an excess of 44.4% vs age- and sex-matched controls.

CONCLUSION: In the near future, the burden of CD will increase tremendously. Few Mediterranean countries are able to face this expanding epidemic alone.

New and developing therapies for celiac disease

The treatment for celiac disease, a removal of gluten in the diet, is safe and effective for the vast majority of patients. There is a large body of evidence that the diagnosis and treatment of those with celiac disease ensures considerable health benefits. Although a gluten-free diet is the principal treatment for celiac disease, it is relatively expensive, inconvenient and difficult to adhere to. For these reasons, there is interest in developing alternative therapies. Emerging research for the treatment of celiac disease has focused on three areas: to decrease gluten exposure, to modify intestinal permeability and to modulate immune activation. Therapies developed thus far consist of enzymes designed to digest gluten and the use of inhibitors of paracellular permeability to decrease the migration of gluten peptides into the lamina propria. Other potential therapeutic maneuvers include the binding of gluten by polymers, the use of tissue transglutaminase (TTG) inhibitors and DQ2 or DQ8 blockers, or modulation of cytokine production. While all represent new and exciting therapies, an ideal therapy should have virtually no side effects similar to a gluten-free diet. A pharmaceutical agent may be used on an intermittent basis, such as following occasional gluten exposure or on a chronic basis to mitigate the effects of potential inadvertent ingestion of gluten.

Clinical management of coeliac disease

OBJECTIVE

To describe the prevalence of Coeliac disease (CD) and its clinical management.

METHODS

Narrative review.

RESULTS

Coeliac disease (CD) is an immune-mediated disorder that primarily affects the gastrointestinal (GI) tract. Recent data suggest a prevalence of about 1% in most Western countries, a figure that likely represents an increase in the prevalence of CD. Risk groups include those who are members of families with individuals who have CD as well as those with Type I diabetes and a variety of autoimmune diseases. Whereas biopsy is the gold standard in diagnosis, serological tests are crucial in determining who should undergo endoscopy and biopsy. HLA testing should be used only to rule out CD. Currently, a gluten-free diet is the only available therapy.

CONCLUSION

In conclusion, CD is one of the most common immune-mediated disorders in the Western world. It should be considered in patients with a number of varying GI and non-GI symptoms, as well as in high-risk groups that include first-degree relatives.

The prevalence of coeliac disease is significantly higher in children compared with adults

BACKGROUND

Some limited studies of coeliac disease have shown higher frequency of coeliac disease in infancy and adolescence than in adulthood. This finding has remained unnoticed and not adequately demonstrated.

AIM

To assess whether there are age and gender differences in coeliac disease prevalence.

METHODS

A total of 4230 subjects were included consecutively (1 to ≥80 years old) reproducing the reference population by age and gender. Sample size was calculated assuming a population-based coeliac disease prevalence of 1:250. After an interim analysis, the paediatric sample was expanded (2010 children) due to high prevalence in this group. Anti-transglutaminase and antiendomysial antibodies were determined and duodenal biopsy was performed if positive. Log-linear models were fitted to coeliac disease prevalence by age allowing calculation of percentage change of prevalence. Differences between groups were compared using Chi-squared test.

RESULTS

Twenty-one subjects had coeliac disease (male/female 1:2.5). Coeliac disease prevalence in the total population was 1:204. Coeliac disease prevalence was higher in children (1:71) than in adults (1:357) (P = 0.00005). A significant decrease of prevalence in older generations was observed [change of prevalence by age of -5% (95% CI: -7.58 to -2.42%)]. In the paediatric expanded group (1-14 years), a decrease of coeliac disease prevalence was also observed [prevalence change: -17% (95% CI: -25.02 to -6.10)].

CONCLUSIONS

The prevalence of coeliac disease in childhood was five times higher than in adults. Whether this difference is due to environmental factors influencing infancy, or latency of coeliac disease in adulthood, remains to be demonstrated in prospective longitudinal studies.

The prevalence of celiac disease in Europe: results of a centralized, international mass screening project

INTRODUCTION

Although the prevalence of celiac disease (CD) has been extensively investigated in recent years, an accurate estimate of CD frequency in the European population is still lacking. The aims of this study were: 1) to establish accurately the prevalence of CD in a large sample of the European population (Finland, Germany, Italy, and UK), including both children and adults; and 2) to investigate whether the prevalence of CD significantly varies between different areas of the European continent.

MATERIALS AND METHODS

Samples were drawn from the four populations. All 29,212 participants were tested for CD by tissue transglutaminase (tTG) antibody test. Positive and border-line findings were further tested for serum endomysial antibodies (EMA). All serological determinations were centrally performed. Small-bowel biopsies were recommended to autoantibody-positive individuals. Previously diagnosed cases were identified.

RESULTS

The overall CD prevalence (previously diagnosed plus anti-tTG and EMA positives) was 1.0% (95% CI 0.9-1.1). In subjects aged 30-64 years CD prevalence was 2.4% in Finland (2.0-2.8), 0.3% in Germany (0.1-0.4), and 0.7% in Italy (0.4-1.0). Sixty-eight percent of antibody-positive individuals showed small-bowel mucosal changes typical for CD (Marsh II/III lesion).

CONCLUSIONS

CD is common in Europe. CD prevalence shows large unexplained differences in adult age across different European countries.

Coeliac disease in autoimmune liver disease: a cross-sectional study and a systematic review

BACKGROUND

Several studies have reported an association between coeliac disease and autoimmune liver disease, but there is little information on the prevalence of coeliac disease in certain autoimmune liver diseases, particularly from non-European, non-American countries.

AIMS

To investigate prevalence of coeliac disease in autoimmune liver disease in Iran and to summarize previous literature.

METHODS

We investigated prevalence of coeliac disease among 100 autoimmune liver disease patients and compared it with the prevalence in healthy individuals. We also performed an extensive search of the English literature in PubMed Database.

RESULTS

We found substantially elevated prevalence of coeliac disease in patients with overlap syndrome (10-15%) compared to the general population (0.1-1%). To a lesser extent, the prevalence was high in patients with autoimmune hepatitis (2-4%). In our systematic review, prevalence of coeliac disease in autoimmune hepatitis in the majority of studies was 4% or more; several studies also reported such prevalence in primary biliary cirrhosis.

CONCLUSIONS

Since coeliac disease is common among patients with autoimmune liver disease, screening autoimmune liver disease patients for coeliac disease is indicated. Although the magnitude of benefit from a gluten-free diet in reversing autoimmune liver disease in patients with coeliac disease is controversial, it may reduce the risk of further complications of coeliac disease.

Celiac disease in Middle Eastern and North African countries: A new burden?

Celiac disease (CD) is now recognized as a common disorder among Middle Eastern (ME) and North African (NA) populations. The aim of this review is to assess the available data regarding CD in the ME and NA and to compare this information with that of Western countries. A literature review was performed using the electronic databases PubMed and Medline (1950-2008) as search engines, and “celiac disease” was used as a Mesh term. The search was limited to ME and NA countries. The prevalence of CD in ME and NA countries among low risk populations is similar to that of Western countries, but is higher in high risk populations such as those with type 1 diabetes. It is underestimated because of lack of clinical suspicion and lack of patient awareness. Clinical presentations in term of gastrointestinal, hematologic, skeletal, and liver manifestations are similar between both populations except for a high prevalence of short stature in some ME and NA countries. Few studies have addressed atypical or silent CD. As in the West, diagnosis is initially made by serological tests and is confirmed by small intestinal biopsies. Gluten-free diet is the main mode of treatment with a higher apparent adherence rate than in the West. Most disease complications result from malabsorption. The disease is strongly associated with HLA DQ2 and to a lesser extent with HLA DQ8 alleles. In conclusion, CD prevalence is underestimated, with little data available about its malignant complications. Disease parameters in the ME and NA are otherwise similar to those in Western countries.