Prevalence of celiac disease in Tunisia: mass-screening study in schoolchildren

Patient and Community Health Global Burden in a World With More Celiac Disease

Celiac disease is one of the most common life-long disorders worldwide, with a prevalence mostly ranging between 0.7% and 2.9% in the general population and a higher frequency in females and well-defined at-risk groups, such as relatives of affected individuals and patients with autoimmune comorbidities. Increasing clinical detection is facilitated by improving awareness, implementation of a case-finding approach, and serology availability for screening at-risk patients, among other factors. Nevertheless, due to huge clinical variability, many celiac disease cases still escape diagnosis in most countries, unless actively searched by proactive policies. The burden of celiac disease is increasing, as is the need for better longitudinal care. Pediatric screening of the general population could represent the road ahead for an efficient intervention of secondary prevention aimed to reduce the social and health burden of celiac disease. This review analyses the epidemiology of celiac disease continent by continent, discusses current strategies to improve the detection of celiac disease, and highlights challenges related to the burden of celiac disease globally.

Population level screening for celiac disease: is now the time?

PURPOSE OF REVIEW

As incidence and prevalence of celiac disease is increasing, subclinical and asymptomatic presentations are more commonly identified through celiac disease screening. However, the United States Preventive Services Task Force released a statement in 2017 maintaining that there is insufficient evidence to recommend general population screening for celiac disease for asymptomatic individuals. This review summarizes the current available evidence on celiac disease screening.

RECENT FINDINGS

Literature demonstrates that by limiting screening to individuals with recognized symptoms, celiac disease diagnosis is frequently delayed or missed entirely. Most individuals with screening-identified celiac disease have previously unrecognized symptoms that improve through treatment with a gluten-free diet. Screening-identified individuals also demonstrate signs of impaired nutrition, growth, bone health, and quality of life which improve with treatment. Overall, celiac disease screening is viewed favorably by those identified through celiac disease screening programs.

SUMMARY

Individuals with screening-identified celiac disease may still incur complications from untreated disease and receive benefit from treatment with a gluten-free diet. More data is needed to determine the cost effectiveness of different mass screening approaches that incorporate the societal perspective towards screening.

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.

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.

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.

The Epidemiology of Celiac Disease in the General Population and High-Risk Groups in Arab Countries: A Systematic Review

Background and Aims

Celiac disease (CD) is possibly the most common autoimmune disorder, which may lead to dietary problems in the Arab region. This paper is aimed at exploring the epidemiology of the celiac disease in Arab countries, including its prevalence, associated risk factors, and clinical patterns.

Methods

An extensive search of the literature was conducted from electronic databases such as PubMed, Embase, and Google Scholar. In total, 134 research papers were retrieved. We extracted studies published from January 1996 to December 2019. Our search was limited to studies published in English. Findings. The review included 35 studies with 22,340 participants from 12 countries and demonstrated a wide variation in the prevalence of CD. The highest prevalence among the general population (3.2%) was reported in Saudi Arabia, and the lowest (0.1%) was reported in Tunisia. Women demonstrated a higher prevalence of celiac disease relative to men. The peak age at diagnosis fell between 1 and 3 years and 9-10 years. Most studies focused on type 1 diabetes. Children with type 1 diabetes have a higher prevalence of CD (range from 5.5% to 20%), while the prevalence of CD in Down's syndrome patients was 1.1% and 10.7% in UAE and Saudi Arabia, respectively. Other autoimmune diseases associated with CD are thyroid disease and irritable bowel disease. The most widely recognized clinical presentation was an inability to flourish and poor weight gain, followed by short stature, abdominal pain, abdominal distension, bloating, and chronic diarrhea.

Conclusion

The prevalence of the celiac disease in Arab countries varies with sex and age. However, we found that celiac disease presented similar clinical characteristics independent of the geographic region. Longitudinal population-based studies are needed to better identify the true burden and determinants of celiac disease.

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.

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.

Identifying and improving adherence to the gluten-free diet in people with coeliac disease

Coeliac disease (CD) is an autoimmune gastrointestinal disorder whereby the ingestion of gluten, a storage protein found in wheat, barley and rye, causes damage to intestinal mucosa with resultant malabsorption, increased risk of anaemia and osteoporosis. Worldwide estimates suggest 1% of the population have CD. With no cure, the only treatment is a gluten-free diet (GFD). Adhering to a GFD can be very challenging; it requires knowledge, motivation and modified behaviours. Assessing adherence to a GFD is methodologically challenging. This review aims to provide an overview of the literature reporting adherence to a GFD in people with CD and the methodological challenges encountered. From six studies it has been reported that rates of adherence to a GFD range between 45 and 90% in patients of different ethnicities with CD. GF dietary adherence can be influenced by age at diagnosis, coexisting depression, symptoms on ingestion of gluten, nutrition counselling, knowledge of GF foods, understanding of food labels, cost and availability of GF foods, receiving GF foods on prescription and membership of a coeliac society. To date only five intervention studies in adults with CD have been undertaken to improve GF dietary adherence. These have included dietary and psychological counselling, and the use of online training programmes, apps, text messages and telephonic clinics. Future interventions should include people of all ethnicities, consider patient convenience and the cost-effectiveness for the healthcare environment.

Screening for coeliac disease in children

AIM

Coeliac disease is a common but markedly under-diagnosed condition, which may lead to serious long-term complications if untreated. Both the diagnostic yield and true incidence have significantly increased during the last few decades and it is now one of the most common chronic gastrointestinal conditions in children. The aim of this review was to summarise the current concepts on screening for coeliac disease in children and adolescents.

METHOD

We conducted a non-systematic literature review of papers published about coeliac disease screening since the year 2000.

RESULTS

Our review showed that the diagnostic yield could be significantly improved by screening for at-risk groups, or even the whole population, but these approaches remain controversial. Evidence suggests that screening for certain high-risk groups could be beneficial, but untargeted mass screening is not currently recommended. However, whether the benefits of an early diagnosis would overcome the challenges of lifelong dietary treatment, especially in asymptomatic individuals who consider themselves healthy, are unclear.

CONCLUSION

There is moderate evidence that screening certain at-risk groups for coeliac disease could be beneficial, but more studies in different settings are needed before large-scale population screening can be recommended.

Current Paediatric Coeliac Disease Screening Strategies and Relevance of Questionnaire Survey

Coeliac disease (CD) is an autoimmune enteropathy triggered by the ingestion of gluten-containing grains in genetically predisposed individuals. Identification of CD in clinical practice is often difficult due to the manifestation of non-specific symptoms and signs, so a relatively significant proportion of CD cases remain undiagnosed. Timely detection of the disease is necessary to provide an appropriate approach to control of the disease treatment, in order to avoid potential complications. This is even more important in the case of children and adolescents, to ensure their proper growth and development. In this review, we discuss the data on the current strategies for CD detection among paediatric populations and the role of questionnaire-based discovery of CD cases in the area of interest. We assume that mass screening is a preferable strategy for finding CD cases within the paediatric population because this could uncover symptomatic, oligosymptomatic, and asymptomatic CD cases. However, under conditions of limited financial resources, screening for CD in risk groups, members of which can be identified using questionnaires, is essential. The pros and cons of CD screening in paediatric populations are presented. These depend on a number of situational criteria (cost-effectiveness, lack of awareness), but screening is designed to improve the detection of the disease and therefore improve the quality of life of patients.

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.

Celiac disease in Saudi children. Evaluation of clinical features and diagnosis

Objectives:

To characterize the clinical presentations and diagnosis including serological tests and histopathological findings in children with celiac disease.

Methods:

All children (<18 years) with confirmed celiac disease diagnosed over a 6 year period at a private tertiary care health care center in Riyadh, Saudi Arabia were studied retrospectively. Information collected included demographics, clinical presentation and diagnostic modalities with serology and small intestinal histology reported by Marsh grading.

Results:

A total of 59 children had confirmed celiac disease. Thirty (50.8%) were male. Median age was 8 years (range 1 to 16 years). The mean duration of symptoms before diagnosis was 2.3 (±1.5) years. Classical disease was present only in 30.5%, whereas 69.5% had either non-classical presentations or belonged to high risk groups for celiac disease such as those with type-1 diabetes, autoimmune thyroiditis, Down syndrome and siblings. Failure to thrive was the most common presentation followed by short stature, abdominal pain and chronic diarrhea. Anti-tissue transglutaminase antibody was positive in 91.5%, and titers were no different between those with classical and non-classical disease. All had Marsh-graded biopsy findings consistent with celiac disease.

Conclusion:

Children with celiac disease usually present with non-classical features. A high index of suspicion needs to be maintained to consider this disorder in the diagnostic workup of pediatric patients. High risk group should be screened early to avoid complications associated with untreated celiac disease.

Mass Screening for Celiac Disease Among School-aged Children: Toward Exploring Celiac Iceberg in Saudi Arabia

OBJECTIVES

We conducted this mass screening study to determine the prevalence of celiac disease (CD) and characterize the celiac iceberg among Saudi pediatric population in Riyadh, the capital city of Saudi Arabia.

METHODS

During the study period (January 2014-June 2016), we have conducted a cross-sectional, mass screening, immunoglobulin A-tissue transglutaminase (TTG-IgA)-based study on 7930 Saudi students from primary and intermediate schools in Riyadh. Students with positive TTG-IgA (>20 U/L) were called in the hospital to undergo a repeat of TTG-IgA; in those with borderline positive TTG-IgA (20-60 U/L), IgA-endomyseal antibody (EMA-IgA) test was performed. Children with TTG-IgA >60 U/L and children with borderline positive TTG-IgA and positive EMA-IgA were advised to undergo upper endoscopy and intestinal biopsies.

RESULTS

We identified 221 students with positive TTG-IgA (2.8%). CD was diagnosed in 119 cases (1.5%, 1:67 Saudi children) (mean age 11.5 ± 2.62 years; girls 81 [68%]). Another 51 children had persistently borderline positive TTG-IgA but negative EMA (0.64%) and the remaining 51 had transiently positive TTG-IgA. We have identified 3 clinical patterns in the screening-identified cases with CD: a silent form (37%), a mild symptomatic form characterized by gastrointestinal symptoms in presence of normal growth or overweight/obesity (48%), and gastrointestinal symptoms associated with impaired growth in 15%.

CONCLUSIONS

Our study provided evidence of a high prevalence of CD among Saudi children (1.5%), a rate that is at least twice the average prevalence rate in Europe and North America.

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.

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 coeliac disease in idiopathic hypoparathyroidism and effect of gluten-free diet on calcaemic control

BACKGROUND

Patients with idiopathic hypoparathyroidism (IH) require variable doses of calcium and 1-α-(OH)D. The reasons for such variability are not clear. As autoimmune mechanisms may play a role in IH, there is a possibility of coexistent coeliac disease with calcium/vitamin D malabsorption.

OBJECTIVE

We assessed the prevalence of coeliac disease and antitissue transglutaminase autoantibodies (anti-tTGAbs) in IH and analysed the effect of a gluten-free diet on calcaemic control.

METHOD

A total of 171 patients with IH and 126 healthy controls were screened for anti-tTGAb. IH patients with anti-tTGAb >20 RU/ml underwent duodenoscopy and intestinal biopsy; those with biopsy-proven coeliac disease were followed up on a gluten-free diet.

RESULTS

Eleven of 171 (6·4%) patients with IH and seven of 126 (5·6%) controls had anti-tTGAb (P = 0·81). There was no difference in the clinical and biochemical parameters at diagnosis and during long-term follow-up of 7·2 ± 4·8 year (mean serum total calcium = 1·88 ± 0·16 vs 1·82 ± 0·36 mmol/l, P = 0·52; phosphorus = 1·81 ± 0·17 vs 1·87 ± 0·36 mmol/l, P = 0·53) in IH patients with and without anti-tTGAb. Although CaSRAb positivity was comparable in the two groups, IH patients with anti-tTGAb had higher TPOAb positivity (45·5% vs 12·8%, P = 0·02). Coeliac disease was diagnosed in only 2/9 patients with IH on biopsy, both of whom showed improved calcaemic control with a gluten-free diet.

CONCLUSION

The prevalence of coeliac autoimmunity (6·4%) and coeliac disease (1·2%) in patients with IH seems to be similar to that in the general population. Notwithstanding this modest prevalence, it is important to be aware of the potential occurrence of coeliac disease with IH and the beneficial effect of a gluten-free diet on calcium control.

Replication of GWAS Coding SNPs Implicates MMEL1 as a Potential Susceptibility Locus among Saudi Arabian Celiac Disease Patients

Celiac disease (CD), a gluten intolerance disorder, was implicated to have 57 genetic susceptibility loci for Europeans but not for culturally and geographically distinct ethnic populations like Saudi Arabian CD patients. Therefore, we genotyped Saudi CD patients and healthy controls for three polymorphisms, that is, Phe196Ser in IRAK1, Trp262Arg in SH2B3, and Met518Thr in MMEL1 genes. Single locus analysis identified that carriers of the 518 Thr/Thr (MMEL1) genotype conferred a 1.6-fold increased disease risk compared to the noncarriers (OR = 2.6; 95% CI: 1.22-5.54; P < 0.01). This significance persisted even under allelic (OR = 1.55; 95% CI: 1.05-2.28; P = 0.02) and additive (OR = 0.35; 95% CI: 0.17-0.71; P = 0.03) genetic models. However, frequencies for Trp262Arg (SH2B3) and Phe196Ser (IRAK1) polymorphisms were not significantly different between patients and controls. The overall best MDR model included Met518Thr and Trp262Arg polymorphisms, with a maximal testing accuracy of 64.1% and a maximal cross-validation consistency of 10 out of 10 (P = 0.0156). Allelic distribution of the 518 Thr/Thr polymorphism in MMEL1 primarily suggests its independent and synergistic contribution towards CD susceptibility among Saudi patients. Lack of significant association of IRAK and SH2B3 gene polymorphisms in Saudi patients but their association in European groups suggests the genetic heterogeneity of CD.

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.

Overview of biomarkers for diagnosis and monitoring of celiac disease

Among the adverse reactions caused by wheat, celiac disease (CD) is the longest studied and best-known pathology. The more recently defined non-celiac gluten sensitivity (NCGS) presents with symptoms which are often indistinguishable from CD. Diagnosis of CD is based on serologic, molecular, and bioptic testing. The IgA anti-transglutaminase (tTG) test is considered highly important, as it shows high sensitivity and specificity and its levels correlate to the degree of intestinal damage. Small bowel biopsy can be avoided in symptomatic patients with IgA anti-tTG levels above 10× the manufacturer's cut-off. Recently, tests of anti-deamidated peptides of gliadin (DGP) have replaced classic anti-native gliadin (AGA) tests. DGP assays have a considerably higher diagnostic accuracy than AGA assays, especially in the IgG class, and can replace anti-tTG tests in patients with selective IgA deficiency. The combination of IgG anti-DGP plus IgA anti-tTG assays show greater sensitivity than a single test, with very high specificity. EMA tests have great diagnostic accuracy but are not recommended by all the latest guidelines because they are observer dependent. Biopsy must still be considered the gold standard for CD diagnosis. HLA-DQ genotyping can be used to screen asymptomatic children and in cases of histology/serology disagreement. About half of NCGS patients are DQ2 positive and have IgG AGA. To diagnose NCGS, first CD and wheat allergy must be excluded; then the wheat dependence of symptoms must be verified by a gluten-free diet and subsequent gluten challenge.

Prevalence of celiac disease among symptom-free children from the Eastern Province of Saudi Arabia

BACKGROUND/AIM

Epidemiological studies of celiac disease (CD) among Saudi children have been performed only within some groups who are at a high risk of developing CD. The aim of this study was to determine the prevalence of CD among symptom-free children from the public schools of the military campus of National Guard in the Eastern Province of Saudi Arabia.

PATIENTS AND METHODS

Between 2012 and 2014, serum samples were collected from 1141 students (age 6-18 years) attending nine public schools of the military campus of National Guard in the Eastern Province of Saudi Arabia. Participants were screened for CD by testing for anti-tissue transglutaminase IgA (IgA-tTG) and IgG antibodies (IgG-tTG). Small intestinal biopsy was offered to all participants who tested positive for IgA-tTG [IgA-tTG >20 relative units (RU)/ml].

RESULTS

Of the 1141 participants, 32 were IgA-tTG positive. Thus, the estimated serology-positive prevalence was 3%. An intestinal biopsy was performed in 10 of the participants with antibody positivity. The biopsy findings of all 10 children were consistent with CD. Thus, the estimated biopsy-confirmed prevalence was about 1%.

CONCLUSIONS

The prevalence of CD was estimated to be about 1% among symptom-free children from the public schools of the military campus of National Guard in the Eastern Province of Saudi Arabia.

A point-of-care test for facing the burden of undiagnosed celiac disease in the Mediterranean area: a pragmatic design study

BACKGROUND

We aimed at assessing the factors that can influence results of the dissemination of an already validated, new generation commercial Point-of-Care Test (POCT) for detecting celiac disease (CD), in the Mediterranean area, when used in settings where it was designed to be administered, especially in countries with poor resources.

METHODS

Pragmatic study design. Family pediatricians at their offices in Italy, nurses and pediatricians in Slovenia and Turkey at pediatricians', schools and university primary care centers looked for CD in 3,559 (1-14 yrs), 1,480 (14-23 yrs) and 771 (1-18 yrs) asymptomatic subjects, respectively. A new generation POCT detecting IgA-tissue antitransglutaminase antibodies and IgA deficiency in a finger-tip blood drop was used. Subjects who tested positive and those suspected of having CD were referred to a Celiac Centre to undergo further investigations in order to confirm CD diagnosis. POCT Positive Predictive Value (PPV) at tertiary care (with Negative Predictive Value) and in primary care settings, and POCT and CD rates per thousand in primary care were estimated.

RESULTS

At tertiary care setting, PPV of the POCT and 95% CI were 89.5 (81.3-94.3) and 90 (56-98.5) with Negative Predictive Value 98.5 (94.2-99.6) and 98.7% (92-99.8) in children and adults, respectively. In primary care settings of different countries where POCT was performed by a different number of personnel, PPV ranged from 16 to 33% and the CD and POCT rates per thousand ranged from 4.77 to 1.3 and from 31.18 to 2.59, respectively.

CONCLUSIONS

Interpretation of POCT results by different personnel may influence the performance of POC but dissemination of POCT is an urgent priority to be implemented among people of countries with limited resources, such as rural populations and school children.

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.

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.

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.

Atypical celiac disease: from recognizing to managing

The nonclassic clinical presentation of celiac disease (CD) becomes increasingly common in physician's daily practice, which requires an awareness of its many clinical faces with atypical, silent, and latent forms. Besides the common genetic background (HLA DQ2/DQ8) of the disease, other non-HLA genes are now notably reported with a probable association to atypical forms. The availability of high-sensitive and specific serologic tests such as antitissue transglutuminase, antiendomysium, and more recent antideamidated, gliadin peptide antibodies permits to efficiently uncover a large portion of the submerged CD iceberg, including individuals having conditions associated with a high risk of developing CD (type 1 diabetes, autoimmune diseases, Down syndrome, family history of CD, etc.), biologic abnormalities (iron deficiency anemia, abnormal transaminase levels, etc.), and extraintestinal symptoms (short stature, neuropsychiatric disorders, alopecia, dental enamel hypoplasia, recurrent aphtous stomatitis, etc.). Despite the therapeutic alternatives currently in developing, the strict adherence to a GFD remains the only effective and safe therapy for CD.

Celiac disease in children and adolescents: special considerations

Although there are many commonalities between adult and pediatric celiac disease (CD), special considerations must be taken into account when working with children and adolescents. In this patient population, there are unique aspects of the epidemiology, pathogenesis, presentation, diagnosis, and management of CD. In terms of management, early and timely recognition of CD can maximize childhood and adolescent development and prevent complications. This requires insight into the unique presentations of CD in the pediatric population. Furthermore, health care providers must use proper screening methods and continue surveillance of at-risk individuals throughout childhood. Potential interventions for primary prevention of CD in children, although not completely understood, may offer some benefit. The goals of this article are to discuss in detail these special considerations when dealing with pediatric 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 clues in celiac disease epidemiology, pathogenesis, clinical manifestations, and treatment

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. It is one of the most common lifelong disorders on a worldwide basis. Celiac enteropathy is the final consequence of an abnormal immune reaction, showing features of both an innate and an adaptive response to gluten prolamins. The clinical spectrum is wide, including cases with either typical intestinal or atypical extraintestinal features, and silent forms. The only available treatment consists in dietary exclusion of grains containing gluten. New pharmacological treatment are currently under scrutiny.

Coeliac disease in Libyan children: a screening study based on the rapid determination of anti-transglutaminase antibodies

BACKGROUND

Coeliac disease is a common disorder in North Africa; however, there are no data on coeliac disease prevalence in Libya.

AIM

(1) To determine coeliac disease prevalence in Libyan schoolchildren by screening with a rapid test for IgA anti-transglutaminase determination on a blood drop; (2) to evaluate the accuracy of the rapid anti-transglutaminase test.

PATIENTS AND METHODS

We screened 2920 students (1452 females and 1468 males) attending school in El Beida (Libya) by the rapid anti-transglutaminase test. Conventional ELISA anti-transglutaminase in rapid test positives and small intestinal biopsy in ELISA positives were performed for coeliac disease diagnosis. Conventional IgA anti-transglutaminase was performed also in 800 rapid test negative subjects.

RESULTS

The rapid anti-transglutaminase test was positive in 50/2920 (1.7%) subjects but only 20/50 were confirmed by the ELISA determination. The diagnosis of coeliac disease was biopsy-confirmed in 19 out of these 20. The serum ELISA IgA anti-transglutaminase was positive in 4 out of 800 rapid test negative children. Coeliac disease prevalence was 0.79-1.13%.

CONCLUSIONS

Coeliac disease in Libyan children is as common as in Europe, affecting around 1% of the general population. The rapid test for IgA anti-transglutaminase determination on a blood drop was not an efficient screening test.

Prevalence of celiac disease in healthy Turkish school children

OBJECTIVES

Epidemiological studies of celiac disease (CD) in Turkey have been performed only within some regions of the country. The aim of this study was to determine the prevalence of CD in Turkish school children.

METHODS

Between 2006 and 2008, serum samples were collected from 20,190 students (age range, 6-17 years) in 139 schools in 62 cities from different regions of Turkey. CD was screened using IgA antitissue transglutaminase (IgA-tTG) and total serum IgA. Subjects with selective IgA deficiency were further tested for IgG-tTG. Serum samples positive for IgA or IgG-tTG were further tested for IgA antiendomysial antibodies (IgA-EMAs) using an indirect immunofluorescence method. Small-intestinal biopsy was offered to all subjects with tTG antibody positivity.

RESULTS

Of the 20,190 subjects, 489 were antibody positive (IgA-tTG only in 270, both IgA-tTG and IgA-EMA in 215, and IgG-tTG in 4). Selective IgA deficiency was detected in 108 patients, and 4 of them were positive for IgG-tTG. An intestinal biopsy was conducted in 215 subjects (IgA-tTG positive in 110, IgA-tTG and IgA-EMA positive in 104, and IgG-tTG positive in 1). The biopsy findings of 95 children were consistent with CD. Thus, the estimated biopsy-proven prevalence was 1:212 children. The positive predictive value (PPV) for IgA-tTG plus EMA was 75.9%. PPV was 44.3% when only IgA-tTG was used.

CONCLUSIONS

We estimate that the prevalence of CD is at least 0.47% in healthy Turkish school children. Screening for IgA-tTG plus EMA provided better results for diagnosis when compared with testing for IgA-tTG alone.

Celiac disease in children and adolescents at a singe center in Saudi Arabia

BACKGROUND AND OBJECTIVES

Celiac disease (CD) is an immune-mediated enteropathy, induced by gluten in genetically susceptible individuals. The objective of this study was to describe the clinical pattern of CD in children from the western region of Saudi Arabia.

DESIGN AND SETTING

Retrospective, hospital-based.

PATIENTS AND METHODS

This study included children with a biopsy-proven diagnosis of CD made between September 2002 and July 2007. Children were admitted to the endoscopy unit for a small-bowel biopsy if they had gastrointestinal symptoms suggestive of CD or if they were positive for a CD-antibody screen performed for the high-risk groups.

RESULTS

Eighty children were identified with a diagnosis of CD. Their mean (SD) age was 9.6 (4.9) years (range, 0.5-18 years). There were 44 (55%) female patients. Forty-one (51%) patients were detected during screening of high-risk groups, while 39 (49%) patients had classical symptoms of malabsorption. The screening also detected asymptomatic patients. Of 65 patients tested, 11 (17%) had elevated liver function tests, which reverted to normal after introduction of a gluten-free diet (GFD) except in one case. Seventy-three (91%) patients were positive for anti-tissue transglutaminase antibodies, 18 (23%), for IgG anti-gliadin antibodies; and 46 (58%), for IgA anti-gliadin antibodies. Forty-one (56%) patients showed good adherence to GFD as assessed by dietary history and the decline in anti-tTG level.

CONCLUSION

CD may present with classical symptoms or be identified through screening programs. Growth and laboratory abnormalities usually improve after introduction of a GFD. Adherence to a GFD remains a problem; therefore, thorough assessment and counseling at the time of diagnosis and ongoing care are crucial.

Are we not over-estimating the prevalence of coeliac disease in the general population?

Until the 1980s, coeliac disease was considered to be a rare disease, but in the 1990s it became clear that it was a frequent condition. Recently, it was suggested to affect 1 out of 100 subjects in the Western world. To understand what the true prevalence of coeliac disease is in the general population, we conducted a systematic review of published papers. The overall prevalence of coeliac disease in the general population appears to be around 1/160 (6.2‰), but this figure varies widely according to the diagnostic criteria used in the original papers. Prevalence obtained with tissue transglutaminase antibodies only was markedly higher than that obtained through a histological diagnosis. We conclude that the prevalence of coeliac disease in the general population has been over-estimated. This is mainly due to tissue transglutaminase antibodies being used as the only diagnostic tool.

HLA-DQ2 and -DQ8 genotypes in celiac and healthy Libyan children

BACKGROUND

Few data are available on the prevalence of celiac disease (CD)-predisposing, HLA-related genes in Arab populations.

AIM OF THE STUDY

To investigate the distribution of HLA-DQ2 and -DQ8 genotypes in Libyan children with CD and healthy controls.

PATIENTS

We tested 31 Libyan children with CD (22 females and 9 males, median age 9.2 years) and 156 Libyan controls (81 females and 75 males, median age 10.9).

METHODS

HLA genes were determined on a drop of dried blood by the DQ-CD Typing Plus kit (DiaGene, Palermo, Italy).

RESULTS

The HLA-DQ pattern of the 31 CD children was: hetero DQ2 (n=15), DQ2 with homo beta2 (10), DQ8 and beta2 positive (3), DQ8 (2), and hetero beta2 (1). The HLA-DQ pattern of the 156 controls was: hetero DQ2 (n=36), hetero beta2 (30), DQ2-DQ8 negative (23), DQ8 (19), alpha5 (14), DQ2 with homo beta (12), homo beta2 (10), DQ8 and beta2 positive (7), and DQ2/DQ8 (5).

CONCLUSIONS

HLA-DQ2 and -DQ8 in CD patients are as common in Libya as in Italy, but the frequency of "high-risk" genotypes is higher in Libyan than Italian patients. The prevalence of HLA-DQ2 and -DQ8 genes in the Libyan general population is higher than in Italy, indicating a strong genetic predisposition to CD.

The spectrum of celiac disease: epidemiology, clinical aspects and treatment

Celiac disease is a gluten-sensitive enteropathy that affects people of all ages worldwide. This disease has emerged as a major health-care problem, as advances in diagnostic and screening methods have revealed its global prevalence. Environmental factors such as gluten introduction at childhood, infectious agents and socioeconomic features, as well as the presence of HLA-DQ2 and/or HLA-DQ8 haplotypes or genetic variations in several non-HLA genes contribute to the development of celiac disease. Growing insight into the variable clinical and histopathological presentation features of this disease has opened new perspectives for future research. A strict life-long gluten-free diet is the only safe and efficient available treatment, yet it results in a social burden. Alternative treatment modalities focus on modification of dietary components, enzymatic degradation of gluten, inhibition of intestinal permeability and modulation of the immune response. A small group of patients with celiac disease (2-5%), however, fail to improve clinically and histologically upon elimination of dietary gluten. This complication is referred to as refractory celiac disease, and imposes a serious risk of developing a virtually lethal enteropathy-associated T-cell lymphoma.

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.

HLA class II polymorphism in children with coeliac disease in Tunisia: is there any influence on clinical manifestation?

OBJECTIVE

To elucidate the HLA DRB1, DQB1 and DQA1 polymorphism in Tunisian children with typical form of coeliac disease (CD) in comparison with those from mass screening (atypical and silent CD).

MATERIALS AND METHODS

We recruited three groups: group I: 40 CD children diagnosed according to the ESPGHAN criteria. group II: 40 healthy controls matched with sex, age and geographic origin. group III: 38 CD children coming from mass screening in schoolchildren. HLA class II DRB1, DQB1 and DQA1 alleles were typed by PCR-sequence-specific primer.

RESULTS

Comparing the groups I and II, we found a pronounced increase of the susceptible alleles HLA DRB1*03 (relative risk, RR = 4.18, Pc = 0.001), DQB1*02 (RR = 7.9, Pc<0.0001) and DQA1*0501 (RR = 4.1, Pc = 0.001). As for protective alleles, we detected a high frequency of DRB1*13 (RR = 0.059, Pc = 0.001), DQA1*0102 (RR = 0.071, Pc = 0.009) and DQB1*06 (RR = 0.125, Pc = 0.0042). Haplotype analysis showed that the main combination observed was the conformation of DQ2 (DQA1*0501-DQB1*02) in 36 patients from group I and 30 from group III. There was no statistically significant difference between the groups I and III according to the distribution of the different alleles.

CONCLUSION

We confirmed in this study the high frequency of DQ2 haplotype in CD patients and we identified new protective alleles DRB1*13, DQA1*0102 and DQB1*06. However, HLA polymorphism seems to have no evident impact on clinical outcome of CD.

Selective IgA deficiency in early life: association to infections and allergic diseases during childhood

Selective IgA deficiency in early life is quite common in Caucasian populations, but it is unclear whether it increases the risk of infections and allergic diseases during childhood. Serum IgA levels were measured in 2423 children at 4 years of age in a Swedish population based birth cohort (BAMSE). Parental questionnaires were repeatedly sent out during the child's first 8 years of life, collecting information about infections and allergic diseases. 14 children (1:173) were found to be IgA deficient at 4 years of age. These children had an increased risk of pseudocroup at year 1 (p<0.01) and food hypersensitivity at year 4 (p<0.05) as compared to IgA sufficient children. No increased risk was observed in the partial IgA deficiency group. The findings suggest that selective IgA deficiency may increase the risk of parentally reported pseudocroup and food hypersensitivity during early childhood.

Severe primary hyperparathyroidism masked by asymptomatic celiac disease

OBJECTIVE

To present a case that illustrates the importance of considering asymptomatic celiac disease (CD) as a possible underlying cause in some cases of normocalcemic primary hyperparathyroidism.

METHODS

We describe the clinical presentation, management, and outcome of a case of severe primary hyperparathyroidism manifesting with normocalcemia, likely attributable to the presence of asymptomatic CD.

RESULTS

A 24-year-old woman presented with a 5-year history of generalized weakness, which had progressed until use of a wheelchair became necessary. She also had sustained low-trauma fragility fractures of the right tibia and left femur. She had no symptoms suggestive of CD. Physical examination revealed severe proximal myopathy. Laboratory data (and reference ranges) were as follows: serum calcium, 2.34 mmol/L (2.1 to 2.6); phosphorus, 0.91 mmol/L (0.90 to 1.50); alkaline phosphatase, 421 U/L (40 to 135); albumin, 37 g/L (35 to 45); parathyroid hormone, 874 ng/L (15 to 65); urine calcium, 3.76 mmol/d (2.5 to 8); and 25-hydroxyvitamin D, <13 nmol/L (22 to 116). She was treated with increasing doses of calcitriol, ergocalciferol, and calcium carbonate, but the serum calcium concentration did not increase substantially (reaching a maximum of 2.70 mmol/L on suprapharmacologic doses of these agents). Malabsorption was considered as an explanation for this apparent resistance to these medications. The result of antibody screening for CD was highly positive, and a distal duodenal biopsy confirmed the diagnosis of CD. A technetium Tc 99m sestamibi scan revealed uptake in the neck that was consistent with a single parathyroid adenoma, which was surgically removed. Treatment with a gluten-free diet, calcium carbonate, and ergocalciferol yielded remarkable clinical, biochemical, and radiologic improvement.

CONCLUSION

Asymptomatic CD may be the underlying cause for some cases of normocalcemic primary hyperparathyroidism, and it should be considered in this setting.

Prevalence of celiac disease in Egyptian children disputes the east-west agriculture-dependent spread of the disease

OBJECTIVES

Celiac disease (CD) seems to be a common disorder in north Africa; however, to our knowledge no data are yet available on its prevalence in Egypt. This study was undertaken to investigate the frequency of CD in Egyptian children.

PATIENTS AND METHODS

We investigated a sample of the general pediatric population (1500 individuals, 656 girls and 844 boys, age range 7 months to 18 years, median age 8.0 years) (group A); 150 children (age range 6 months to 13 years, median age 16 months) admitted for diarrhea or failure to thrive (group B); and 250 children and adolescents with type 1 diabetes (group C). The screening test was serum class A anti-transglutaminase (anti-tTG) antibody; immunoglobulin A (IgA) antiendomysium, total IgA, and IgG anti-tTG, and small bowel biopsy was performed for confirmation of diagnosis.

RESULTS

In group A, 8 of 1500 children fulfilled the criteria for CD diagnosis; the prevalence of CD was at least 1 in 187 individuals (0.53%; 95% CI 0.17%-0.89%). In group B, 7 of 150 children had CD (4.7%, 95% CI 1.4-7.9). In group C, 16 of 250 sera showed positive results to both the IgA anti-tTG and the IgA antiendomysium test (6.4%; 95% CI 3.4-9.4).

CONCLUSIONS

Celiac disease is a frequent disorder among Egyptian children, both in the general population and in at-risk groups. Therefore, our data do not support the theory of a Middle East-Europe CD prevalence gradient secondary to the pattern of agriculture spreading from the so-called Fertile Crescent.