HLA DQA1-DQB1 genotypes in Bedouin families with celiac disease

Bedouin Children With Celiac Disease: Less Symptoms but More Severe Histological Features at Presentation

Background: The prevalence of celiac disease (CD) has dramatically increased with wide variability in clinical presentations between different geographical areas. However, the contribution of ethnic disparities in pediatric celiac disease is still unclear, especially in patients of Bedouin origin. Objective: We aimed to compare the clinical presentation and histological severity of celiac disease between Bedouin and Jewish children in southern Israel. Methods: This is a retrospective study in which we collected the demographic and clinical data, laboratory results, and histological severity of CD in two ethnic groups: Bedouins and Jews. The study included patients who were diagnosed between 1997 and 2015 in a tertiary hospital in southern Israel. Results: Data from 844 children with CD (271 Jewish and 573 Bedouins), 505 females (59.8%), were analyzed. Gastrointestinal symptoms and diabetes were more prevalent among the Jewish population (p < 0.001 and p = 0.008, respectively), while family history, failure to thrive, iron deficiency anemia, and histological severity were significantly more prevalent among the Bedouin group. Upon multivariate logistic regression analysis, only the presence of iron deficiency anemia and Bedouin origin were associated with more advanced histological disease (OR of 2.03 (95% C.I 1.31; 4.308) (P < 0.009) and OR 1.78 (95% C.I 1.31; 4.308) (P < 0.003) respectively). Conclusion: The clinical presentation of celiac disease in Bedouin children is characterized by anemia with less gastrointestinal symptoms, but more severe histological damage. These differences might be explained either by a delay in the diagnosis of the disease in this population or by variable environmental, cultural, and nutritional factors unique to this ethnic group.

HLA-DQ2/DQ8 frequency in adult patients with celiac disease, their first-degree relatives, and normal population in Turkey

BACKGROUND/AIMS

Celiac disease is an autoimmune, familial disease that results in susceptibility to gluten in cereal and cereal products in genetically susceptible individuals. The aim of the present study was to investigate the presence of HLA-DQ2/DQ8 in patients with celiac disease, their first-degree relatives, and healthy community.

MATERIALS AND METHODS

HLA-DQ2/DQ8 analysis was performed in adult patients with celiac disease >18 years old (94 patients), their first-degree relatives (89 people), and healthy group (102 individuals). Anemia, osteoporosis, and diarrhea were interrogated in the celiac patient group and also anti-tissue transglutaminase, anti-endomysium, and anti-gliadin antibodies were recorded.

RESULTS

There was a significant relationship between HLA-DQ2/DQ8 presence in all groups, and the distribution of HLA-DQ2/DQ8 in all groups was different (p=0.000). No statistically significant correlation was found between the HLA tissue groups and diarrhea (p=0.087), osteoporosis (p=0.215), anemia (p=1.000), tissue transglutaminase antibodies (p=0.295), anti-gliadin antibodies (p=0.104), and anti-endomysium antibodies (p=0.243) in the celiac patient group.

CONCLUSION

HLA-DQ2/DQ8 can be used to diagnose celiac disease particularly when the tests are useless and to screen first-degree relatives.

The incidence of HLA-DQ2/DQ8 in Turkish children with celiac disease and a comparison of the geographical distribution of HLA-DQ

Introduction

Celiac disease (CD) is an auto-immune enteropathy that occurs in genetically pre-disposed people as a result of the consumption of gluten-containing foods.

Aim

To identify the incidence of HLA-DQ2 and HLA-DQ8 observed in children with CD.

Material and methods

In this study, we focused on children ranging in age from 2 to 18 years and diagnosed with celiac disease. In our patients diagnosed with CD, in addition to tissue transglutaminase antibodies (anti-tTG), we also evaluated HLA-DQ2 B1 and HLA-DQ8 B1 alleles using the method of polymerase chain reaction (PCR)/sequence-specific oligonucleotide probes (Luminex^®). The detection of 0201/0202 for HLA-DQ2 allele and 0302 for HLA-DQ8 allele was accepted as a positive result.

Results

The mean age of our patients with celiac disease was 7.42 ±3.18 years, and the female/male ratio was 1.5/1. Seventy-six percent of our patients were HLA-DQ2 and/or HLA-DQ8 positive, 67% were HLA-DQ2 positive, and 25% were HLA-DQ8 positive. Nevertheless, 24% of them were HLA-DQ2 and HLA-DQ8 negative. The incidence of HLA-DQ2 in the control group was 18.8% with a significant difference compared to the HLA-DQ2 incidence in the patient group (67%) (p < 0.05). Similarly the HLA-DQ8 incidence in the control group (5.7%) was significantly lower than the incidence in the patient group (25%) (p < 0.05).

Conclusions

The incidence of the patients diagnosed with CD, who are HLA-DQ2 and HLA-DQ8 negative, varies among different populations.

Human leukocyte antigen DQ2.2 and celiac disease

Patients with celiac disease (CD) lacking both human leukocyte antigen (HLA)-DQ2.5 in cis (DQA1*05:01, DQB1*02:01) or trans (DQA1*05:05, DQB1*02:02) configuration and HLA-DQ8 (DQA1*03:01, DQB1*03:02) are considered to be rare. Therefore, absence of these genotypes is commonly used to exclude the diagnosis of CD. To investigate whether this approach is justified, the HLA-distribution in 155 children with CD was studied. A total of 139 (89.7%) patients carried HLA-DQ2.5. Of the remaining patients, 7 (4.5%) carried HLA-DQ8. Interestingly, the 9 (5.8%) patients lacking HLA-DQ2.5 and HLA-DQ8 carried HLA-DQA1*02:01 and -DQB1*02:02 (HLA-DQ2.2). Therefore, HLA-DQ2.2 should be included as an important HLA-type related to CD.

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.

The Prevalence of the Celiac Disease Among Urban Bedouin Population in Israel

Background

Celiac disease (CD) is a common, but often under-diagnosed condition with possible serious complications. CD, having a prevalence of about 1% is more common than once thought. Only limited research is available comparing differences between adults and children. A comprehensive Medline search was conducted. No data was found concerning the prevalence of CD among the adult Bedouin population.

Methods

The research is retrospective and descriptive. The objective of our research was to determine the prevalence of the CD within adult and child Bedouin populations in urban Israel. A report of all of diagnosed CD patients extracted from the medical computerized information system (“Clicks”).

Results

In our sample we found the prevalence was 0.51% in children and 0.12% in adults.

Conclusion

In our opinion, one of reasons for the low prevalence level in the Bedouin community might be that typical CD symptoms are less prominent in Bedouin communities than in other communities. But no doubt hypo-diagnosis does exist. We suppose more advanced research about the nature and typical clinical manifestations of CD within the Bedouin population need to be investigated. Medical personnel working within the Bedouin community needs information concerning CD and the characteristics of diagnosis and treatment in the Bedouin community. The Bedouin community itself needs more information concerning CD and the importance of treatment, which could also improve early diagnosis and compliance.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease

OBJECTIVE

Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved.

METHODS

A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing.

RESULTS

In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative.

CONCLUSIONS

The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

HLA DQ gene dosage and risk and severity of celiac disease

BACKGROUND & AIMS

Celiac disease (CD) is a chronic inflammatory disorder of the small intestine that is strongly associated with certain HLA molecules encoded by DQA and DQB genes. The aim of this study was to examine the role of DQA and DQB alleles in determining the risk for and the age of onset and severity of CD in an American population.

METHODS

High-resolution class 2 HLA genotyping was performed in a population-based sample (n = 84) of southeastern Minnesota residents with CD and a comparable control group (n = 102) to determine the contribution of DQA and DQB alleles to disease risk. Logistic regression modeling was used to examine the relative and absolute risks of CD.

RESULTS

Ninety-seven percent of CD patients carried both of the HLA alleles, DQA1*05 and DQB1*02. Those who carried a second allele of DQB1*02 were 5 times more likely to have CD than those with just one (95% confidence interval, 1.4-18.1). The carriage of 2 copies of DQB1*02 did not predict either an earlier age of onset or severity of disease.

CONCLUSIONS

Both HLA alleles DQA1*05 and DQB1*02 are associated with a greatly increased risk of CD, although the latter has the greater effect. Carrying 2 copies of DQB1*02 was associated with an even greater risk for disease but did not predict an earlier age of onset and diagnosis or disease severity. Assessing the copy number of the DQB1*02 allele might allow for the stratification of disease risk.

An autosomal genome-wide screen for celiac disease in Bedouin families

Celiac disease is a common, familial autoimmune disease caused by exposure to gliadin in wheat, and related prolamins in barley and rye. The prevalence of the disease is approximately 1:133. Celiac disease can cause significant morbidity. The only treatment is a gluten-free diet. A genome-wide search of 405 microsatellite markers was performed on samples from 18 Bedouin families with a minimum of two cases of celiac disease. Non-parametric and parametric (including both dominant and recessive models of inheritance) linkage analyses were performed. The most significant genome-wide linkage evidence was at chromosome 3p26 with an HLod of 3.21, under the dominant model. The only other HLod or NPL greater than 2 was at 4q35, with an HLod of 2.15 under a dominant model. The region at 3p26, previously reported in two linkage analyses, harbors interleukin receptor genes, plausible candidates for celiac disease.

Familial steroid-sensitive nephrotic syndrome in Southern Israel: clinical and genetic observations

Reports on genetically informative steroid-responsive (sensitive) idiopathic nephrotic syndrome (SSNS) families are lacking. We studied an extended SSNS Bedouin (B) family with a high rate of consanguinity. The clinical presentation and steroid response of its 11 affected individuals were similar to those of sporadic SSNS (spontaneous remission towards puberty and minimal change disease by kidney biopsy). Genome-wide linkage analysis, using a 382 microsatellite-markers mapping set and additional markers adjacent to 80 candidate genes of the index family, did not support linkage to any chromosomal locus. Retrospective analysis of all additional children with SSNS treated by our institution in the past 20 years (n=96, 50% of them of Jewish origin) revealed another five non-related B families with 2-3 first-degree cousins affected with SSNS in each. The overall familial SSNS rate among the B population (excluding the index family) was 28%, compared with 4% among Jews (Js) (OR 1.8-64, P<0.005). There were more Bs with simple SSNS than there were Js (71% and 40%, respectively; OR 3.58, 95% CI 1.41-9.23, P<0.01). In summary, SSNS in this index family was not linked to any of the presently known chromosomal loci nor predicted to be caused by mutation in any one of a list of genes associated with nephrotic syndrome (NS). The presence of other B families affected by SSNS supports the role for susceptibility genes enrichment, exposing highly consanguineous populations to an increased incidence of SSNS.

Celiac disease and HLA in a Bedouin kindred

We report the prevalence of celiac disease (CD) and its relationship with other autoimmune diseases and HLA haplotypes in a Bedouin kindred. Of 175 individuals sampled and typed for autoantibodies and HLA class II genotypes, six (3.4%) members had CD, and an additional 10 (5.7%) members tested positive for autoantibodies to transglutaminase (TgAA+). Several CD/TgAA+ relatives also had islet cell antigen or adrenal autoimmunity. Affected relatives are more closely related than expected from the pedigree relationships of all family members and were more often the offspring of consanguineous marriages. Individuals with CD or TgAA+ were enriched for DRB1*0301-DQA1*0501-DQB1*0201, a haplotype previously reported as high risk for CD. There was also an increased frequency of DQB1*0201/DQB1*0201 homozygotes among affected relatives. We found no evidence that DRB1*0701-DQA1*0201-DQB1*0201/DRB1*11-DQA1*0501-DQB1*0301 is a high-risk genotype, consistent with other studies of Arab communities. In addition, a nonparametric linkage analysis of 376 autosomal markers revealed suggestive evidence for linkage on chromosome 12p13 at marker D12S364 (NPL = 2.009, p = 0.0098). There were no other significant results, including the HLA region or any other previously reported regions. This could reflect the reduced power of family-based linkage and association analyses in isolated inbred populations.

Infertility and celiac disease: do we need more than one serological marker?

OBJECTIVES

Celiac disease (CD) prevalence is higher in women with infertility. Our study aims were to evaluate the prevalence of undiagnosed CD in Arab infertile women and to explore the usefulness of using more than one serological marker in the diagnostic screening for CD in this population.

METHODS

Women with unexplained infertility (n = 192) and age-matched healthy controls (n = 210) were prospectively enrolled. Serum was tested for human tissue transglutaminase antibodies (TTG), antiendomysial antibodies (EMA), and immunoglobulin A. Intestinal biopsy was offered to women with positive serology or immunoglobulin A (IgA) deficiency.

RESULTS

CD was diagnosed in five infertile women (2.65%) and in one control (0.5%) (p = 0.11). Gastrointestinal complaints were present in 60% (three of five) of women with CD and 11.8% (22 of 187) of women without CD (p = 0.017). Anemia was reported in 80% of infertile women with CD and 4.8% of infertile women without CD (p = 0.0001).

CONCLUSIONS

Undiagnosed CD is prevalent in Arab infertile women as well as in Arab women in general. CD in Arab infertile women is frequently associated with gastrointestinal complaints and anemia. EMA testing is sufficient in suspected cases.

Genomewide search and association studies in a Finnish celiac disease population: Identification of a novel locus and replication of the HLA and CTLA4 loci

It has been reported that celiac disease (CD) is strongly associated with the HLA-DQ2 alleles DQA1*0501 and DQB1*0201. However, this association only accounts for a portion of the genetic component of CD. Several non-HLA loci and candidate genes that potentially contribute to CD susceptibility have been reported, but have not been confirmed. The aim of this study was to identify loci that contribute to disease susceptibility in a CD population from Finland. We performed a genomewide linkage scan and identified two regions of significant linkage to CD (6p and 2q23-32) and one region of suggestive linkage (10p). We also performed targeted typing and analyses that replicated the associations of the HLA and CTLA4 loci.