Prevalence of celiac disease among first degree relatives of Brazilian celiac patients

Prediction Models for Celiac Disease Development in Children From High-Risk Families: Data From the PreventCD Cohort

BACKGROUND & AIMS

Screening for celiac disease (CD) is recommended in children with affected first-degree relatives (FDR). However, the frequency of screening and at what age remain unknown. The aims of this study were to detect variables influencing the risk of CD development and develop and validate clinical prediction models to provide individualized screening advice.

METHODS

We analyzed prospective data from the 10 years of follow-up of the PreventCD-birth cohort involving 944 genetically predisposed children with CD-FDR. Variables significantly influencing the CD risk were combined to determine a risk score. Landmark analyses were performed at different ages. Prediction models were created using multivariable Cox proportional hazards regression analyses, backward elimination, and Harrell's c-index for discrimination. Validation was done using data from the independent NeoCel cohort.

RESULTS

In March 2019, the median follow-up was 8.3 years (22 days-12.0 years); 135/944 children developed CD (mean age, 4.3 years [range, 1.1-11.4]). CD developed significantly more often in girls (P = .005) and in Human Leukocyte Antigen (HLA)-DQ2 homozygous individuals (8-year cumulative incidence rate of 35.4% vs maximum of the other HLA-risk groups 18.2% [P < .001]). The effect of homozygosity DR3-DQ2/DR7-DQ2 on CD development was only present in girls (interaction P = .04). The prediction models showed good fit in the validation cohort (Cox regression 0.81 [0.54]). To calculate a personalized risk of CD development and provide screening advice, we designed the Prediction application https://hputter.shinyapps.io/preventcd/.

CONCLUSION

Children with CD-FDR develop CD early in life, and their risk depends on gender, age and HLA-DQ, which are all factors that are important for sound screening advice. These children should be screened early in life, including HLA-DQ2/8-typing, and if genetically predisposed to CD, they should get further personalized screening advice using our Prediction application.

TRIAL REGISTRATION NUMBER

ISRCTN74582487 (https://www.isrctn.com/search?q=ISRCTN74582487).

Clinical Presentation in Children With Coeliac Disease in Central Europe

OBJECTIVES

During the past decades, there has been a shift in the clinical presentation of coeliac disease (CD) to nonclassical, oligosymptomatic, and asymptomatic forms. We assessed clinical presentation of CD in children and adolescents in Central Europe.

METHODS

Paediatric gastroenterologists in 5 countries retrospectively reported data of their patients diagnosed with CD. Clinical presentation was analyzed and the differences among very young (<3 years) and older children and adolescents were studied.

RESULTS

Data from 653 children and adolescents (median age 7 years 2 months; 63.9% girls) from Croatia, Germany, Hungary, Italy, and Slovenia were available for the analysis. One fifth (N = 134) of all children were asymptomatic. In symptomatic children, the most common leading symptom was abdominal pain (33.3%), followed by growth retardation (13.7%) and diarrhoea (13.3%). The majority of symptomatic children (47.6%; N = 247) were polysymptomatic. Abdominal pain was the most common symptom in polysymptomatic (66.4%) as well as in monosymptomatic children (29.7%). Comparing clinical presentation of CD in very young children (younger than 3 years) with older children (3 years or older), we found that symptoms and signs of malabsorption were significantly more common in younger (P < 0.001), whereas abdominal pain and asymptomatic presentation were more common in older children and adolescents (both P < 0.001).

CONCLUSION

In children with CD, abdominal pain has become the most common symptom. However, in younger children, symptoms of malabsorption are still seen frequently. This raises a question about the underlying mechanism of observed change in clinical presentation in favour of nonclassical presentation and asymptomatic disease at certain age.

Towards an individual screening strategy for first-degree relatives of celiac patients

Celiac disease (CD) is known to be more prevalent in first-degree relatives of patients. In this retrospective cohort study of 609 relatives between 1994 and 2016, we investigated the effect of sex, HLA type, and age at time of index celiac diagnosis. Pearson's chi-square test and Kaplan-Meier survival analysis were used as statistical analyses. CD screening was carried out for 427 relatives (70%), resulting in a prevalence of 15%. HLA typing in 335 relatives showed HLA-DQ2/DQ8 positivity in 87.5%. In 63% of children and all parents, celiac disease was diagnosed at first screening. It was diagnosed significantly more often in females, HLA-DQ2 homozygosity, and children (all p < 0.05). In children aged 0-1 year at time of index diagnosis, celiac disease was diagnosed after consecutive screening in 58%, after 3.9 ± 2.5 (max 10) years (p < 0.001).Conclusion: Future screening policies for relatives of celiac patients should include retesting, especially in HLA-positive relatives younger than 10 years of age. In addition, one-time celiac-specific antibody testing alone could be sufficient to rule out the disease in adolescent siblings and parents of newly diagnosed celiac patients. What is Known: • Celiac disease is more prevalent in first-degree relatives of celiac patients (risk 3-12%). • HLA-DQ2 homozygous sisters/daughters are at highest risk (25%). What is New: • If younger than 10 years of age, repeated testing is necessary in HLA-DQ2/DQ8-positive first-degree relatives when celiac disease is diagnosed in a family. • One-time celiac-specific antibody testing alone could be sufficient to rule out the disease in adolescent siblings and parents of newly diagnosed celiac patients.

HLA Profile of Celiac Disease among First-Degree Relatives from a Tertiary Care Center in North India

OBJECTIVE

To study the prevalence of Celiac disease (CD) in first-degree relatives (FDR) of CD children.

METHODS

This observational study was performed in FDR (parents and siblings) of consecutive newly diagnosed cases of CD enrolled from January 2011 through March 2012. Screening for CD in FDR was done using IgA tissue transglutaminase (tTG) levels in serum and the seropositive subset underwent upper gastrointestinal (UGI) endoscopy and biopsy to confirm the disease. In addition, HLA analysis for CD was performed in most of the index cases and FDR.

RESULTS

Of 202 FDR of the 64 index cases with CD, 17.3 % (35/202) were seropositive for IgA tTG while confirmed biopsy proven CD was diagnosed in 10.2 % (8/78) of children and 8.1 % (10/124) of adults. HLA DQ2/DQ8 was positive in 96.7 % of the index cases and all FDR with confirmed CD.

CONCLUSIONS

The prevalence of CD among FDR is 9 fold higher than the general population. High prevalence of CD in presence of anemia and short stature in seropositive FDR in index study indicates need of targeted screening of this subgroup for the presence of CD.CD is unlikely in the absence of HLADQ2/DQ8.

Structural and Functional Changes in the Tight Junctions of Asymptomatic and Serology-negative First-degree Relatives of Patients With Celiac Disease

BACKGROUND

Ten to 15% of first-degree relatives (FDRs) of celiac disease (CeD) patients develop CeD. Although intestinal barrier functions (intestinal permeability) are abnormal in the subset of serology-negative FDRs, what leads to the abnormal barrier function is not known.

GOALS

To study the ultrastructure and functions of tight junctions in serology-negative FDRs of CeD patients.

STUDY

The intestinal permeability was measured in 97 asymptomatic and anti-tissue transglutaminase antibody (anti-tTG Ab)-negative FDRs (using the lactulose mannitol ratio) and in 75 controls. The ultrastructure of tight junctions using transmission electron microscopy, and the expression of key tight junction proteins (claudin-2, claudin-3, occludin, JAM-A, and ZO-1) and zonulin using real-time PCR and immunohistochemistry were assessed in anti-tTG Ab-negative, HLA-DQ2/-DQ8-positive FDRs having normal villi and in disease controls. In addition, the serum zonulin level was measured in 172 anti-tTG Ab-negative FDRs and 198 controls.

RESULTS

The intestinal permeability was significantly increased in FDRs than in controls. Ultrastructural abnormalities such as dilatation of the tight junction (P=0.004) and loss of the pentalaminar structure (P=0.001) were more common in FDRs than in disease controls. There was significant underexpression of tight junction proteins ZO-1 (P=0.040) and occludin (P=0.041) in FDRs. There was no significant difference in the serum zonulin level between FDRs and controls (P=0.154).

CONCLUSIONS

Even asymptomatic, anti-tTG-Ab-negative FDRs with a normal villous histology have both ultrastructural and functional abnormalities in tight junctions. These findings are indirect evidence of the presence of tight junction abnormalities before the onset of the disease and may have therapeutic implications.

Prevalence of celiac disease among first-degree relatives of Indian celiac disease patients

BACKGROUND

Celiac disease, once thought to be uncommon in Asia, is now recognized in Asian nations as well. We investigated the prevalence of celiac disease in first-degree relatives of celiac disease patients followed in our centre.

METHODS

First-degree relatives were screened prospectively for celiac disease using questionnaire-based interview and anti-tissue transglutaminase antibody. Serology positive first-degree relatives underwent duodenal biopsies. Diagnosis of celiac disease was made based on positive serology and villous abnormality Marsh grade 2 or higher. Human leucocyte antigen DQ2/-DQ8 was also assessed in 127 first-degree relatives.

RESULTS

434 first-degree relatives of 176 celiac disease patients were prospectively recruited; 282 were symptomatic (64.9%), 58 were positive for serology (13.3%). Seroprevalence was higher in female than in males (19% vs 8.5%; p=0.001) and highest in siblings (16.9%) than parents (13.6%) and children (5.9%) of celiac patients (p=0.055); 87.4% first-degree relatives were human leucocyte antigen-DQ2/-DQ8 positive. Overall prevalence of celiac disease was 10.9% amongst first-degree relatives.

CONCLUSIONS

The prevalence of celiac disease in first-degree relatives of celiac disease patients was 10.9% in our cohort, and 87% had human leucocyte antigen-DQ2 or -DQ8 haplotype. All first-degree relatives of celiac disease patients should be screen for celiac disease even if asymptomatic or with atypical manifestations.

Risk of Celiac Disease in the First- and Second-Degree Relatives of Patients With Celiac Disease: A Systematic Review and Meta-Analysis

OBJECTIVES

First-degree relatives (FDRs) of patients with celiac disease (CD) are at high risk for CD and prevalence among them varies from 1.6 to 38%. The risk of having CD among FDRs if the FDR is sister, brother, mother, father, son, or daughter of index patient with CD is not known. We conducted a meta-analysis and calculated pooled prevalence of CD among FDRs, second-degree relatives (SDRs), and specific relations with index patient.

METHODS

On search of literature, 2,259 articles appeared of which 54 articles were included in this meta-analysis. Diagnosis of CD was based on standard criteria.

RESULTS

Pooled prevalence of CD was 7.5% (95% confidence interval (CI) 6.3%, 8.8%) in 10,252 FDRs and 2.3% (95% CI 1.3%, 3.8%) in 642 SDRs. Pooled prevalence of CD was highest in siblings (8.9%), followed by offsprings (7.9%) and parents (3.0%). Female FDRs had higher prevalence than male FDRs (8.4% vs. 5.2%, P=0.047). While sisters and daughters of index patient had the highest risk of having CD (1 in 7 and 1 in 8, respectively), the risk was 1 in 13 in sons, 1 in 16 in brothers, 1 in 32 in mothers, and 1 in 33 in fathers. There were also differences in the pooled prevalence of CD in FDRs according to their geographic location.

CONCLUSIONS

Pooled prevalence of CD among FDRs is 7.5% and varies considerably with their relationship with the index patient. The risk of CD in FDRs also varies according to gender and geographical location.

Celiac Disease: Ten Things That Every Gastroenterologist Should Know

There are 10 things that all gastroenterologists should know about celiac disease (CD). (1) The immunoglobulin A tissue transglutaminase is the single best serologic test to use for the detection of CD. (2) CD can be recognized endoscopically, and water immersion enhances villi detection, although a normal endoscopic appearance does not preclude the diagnosis. (3) It is recommended that 4 biopsies be taken from the second part of the duodenum and 2 bulb biopsies be taken at the 9 o'clock and 12 o'clock positions to maximize the sensitivity for histologic confirmation of CD. (4) Consider serologic testing of first-degree relatives, patients with type 1 diabetes mellitus, Down's, Turner's, and Williams' syndromes, as well as those with premature osteoporosis, iron deficiency, abnormal liver biochemistries, and other manifestations of CD. (5) Patients already on a prolonged gluten-free diet (GFD) should be tested for the presence of HLA DQ2 or DQ8, thereby avoiding the need for further evaluation of CD in non-allelic carriers. (6) The basic treatment of CD is a strict, lifelong GFD, enabled by an expert dietitian. (7) Newly diagnosed adults with CD should be assessed for micronutrient deficiencies (iron, B12, folate, zinc, copper), fat soluble vitamin deficiencies (vitamin D), and bone densitometry. (8) All patients diagnosed with CD should have clinical follow-up to ensure response and adherence to a GFD. (9) In those with persistent or relapsing symptoms, the robustness of the original diagnosis should be reviewed, gluten exposure sought, and a systematic evaluation for alternative and associated diseases performed. (10) Evaluate those with refractory disease for malignant transformation.

Prevalence of celiac disease in latin america: a systematic review and meta-regression

BACKGROUND

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in susceptible individuals, and its prevalence varies depending on the studied population. Given that information on CD in Latin America is scarce, we aimed to investigate the prevalence of CD in this region of the world through a systematic review and meta-analysis.

METHODS AND FINDINGS

This was a two-phase study. First, a cross-sectional analysis from 981 individuals of the Colombian population was made. Second, a systematic review and meta-regression analysis were performed following the Preferred Reporting Items for Systematic Meta- Analyses (PRISMA) guidelines. Our results disclosed a lack of celiac autoimmunity in the studied Colombian population (i.e., anti-tissue transglutaminase (tTG) and IgA anti-endomysium (EMA)). In the systematic review, 72 studies were considered. The estimated prevalence of CD in Latin Americans ranged between 0.46% and 0.64%. The prevalence of CD in first-degree relatives of CD probands was 5.5%. The coexistence of CD and type 1 diabetes mellitus varied from 4.6% to 8.7%, depending on the diagnosis methods (i.e., autoantibodies and/or biopsies).

CONCLUSIONS

Although CD seems to be a rare condition in Colombians; the general prevalence of the disease in Latin Americans seemingly corresponds to a similar scenario observed in Europeans.

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 in children from Madeira island and its prevalence in first degree relatives

CONTEXT

It is well recognized that celiac disease is an immune-mediated systemic disorder highly prevalent among relatives of celiac patients.

OBJECTIVES

The aim of this study is to determine the prevalence of celiac disease in a group of first degree relatives of celiac children, and to access the frequency of human leukocyte antigen HLA-DQ2 and DQ8 in celiac disease patients and their affected relatives.

METHODS

A survey was conducted of 39 children with celiac disease with follow-up in the Pediatric outpatient's clinic of Dr. Nélio Mendonça Hospital, in Madeira Island, Portugal. Were invited 110 first degree relatives to undergo serological screen for celiac disease with IgA antibody to human recombinant tissue transglutaminase (IgA-TGG) quantification. In all seropositive relatives, small intestinal biopsy and HLA typing was recommended.

RESULTS

HLA- typing was performed in 38 celiac patients, 28/74% DQ2 positive, 1/2% DQ8 positive and 9/24% incomplete DQ2. Positive IgA-TGG was found in five out of the 95 relatives, and CD was diagnosed in three of them. Three relatives had the presence of HLA-DQ2, two were DQ2 incomplete (DQB1*02).

CONCLUSIONS

The prevalence of celiac disease among first degree celiac patients´ relatives was 3.1%, 4.5 times higher than the general Portuguese population (0,7%) witch reinforces the need of extensive diagnostic screening in this specific group. HLA-DQ2 typing may be a tool in the diagnostic approach.

Celiac disease in adult patients: specific autoantibodies in the diagnosis, monitoring, and screening

The increasing prevalence of celiac disease (CD), especially in adults, its atypical clinical presentation, and the strict, lifelong adherence to gluten-free diet (GFD) as the only option for healthy state create an imperative need for noninvasive methods that can effectively diagnose CD and monitor GFD. Aim. Evaluation of anti-endomysium (EmA) and anti-tissue transglutaminase IgA (tTG-A) antibodies in CD diagnosis, GFD monitoring, and first degree relatives screening in CD adult patients. Methods. 70 newly diagnosed Greek adult patients, 70 controls, and 47 first degree relatives were tested for the presence of EmA and tTG-A. The CD patients were monitored during a 3-year period. Results. EmA predictive ability for CD diagnosis was slightly better compared to tTG-A (P = 0.043). EmA could assess compliance with GFD already from the beginning of the diet, while both EmA and tTG-A had an equal ability to discriminate between strictly and partially compliant patients after the first semester and so on. Screening of first degree relatives resulted in the identification of 2 undiagnosed CD cases. Conclusions. Both EmA and tTG-A are suitable markers in the CD diagnosis, in the screening of CD among first degree relatives, having also an equal performance in the long term monitoring.

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.

Autoantibodies in relatives of celiac disease patients: a follow-up of 6-10 years

CONTEXT

Autoimmune diseases are 3 to 10 times more frequently in patients with celiac disease and their relatives than in the general population.

OBJECTIVE

To investigate a broad spectrum of autoantibodies in celiac disease relatives from Southern Brazil, in a serological follow-up of 6-10 years, aiming to associate with other autoimmune diseases, degree of parentage, demographic and clinical data.

METHODS

Serum samples of 233 relatives were analyzed in two different phases: n = 186 in phase I (1997-2000) and n = 138 (being 91 = follow-up group and 47 = newly tested) in phase II (2006-2007). As controls, 100 unrelated individuals were evaluated. Autoantibodies to smooth muscle, mitochondrial, liver-kidney microssome, parietal cell and thyroid microssome were tested by indirect immunofluorescence.

RESULTS

A significant increase of autoantibodies, in both phases, was observed in the relatives when compared to the non-relatives (P = 0.0064), specifically to anti-thyroid microssome and anti-parietal cell. In both phases, the female/male proportion of autoantibodies was of 4:1 to 3:1 (P<0.041). The frequency of autoantibodies amongst 1st and 2nd degree relatives was 11.8% and 9.68% in phase I and 4% and 6.67% in phase II.

CONCLUSION

Celiac disease relatives presented other autoantibodies and serological screening is a useful instrument for identifying autoimmune diseases along the years.

Celiac disease in first degree relatives of celiac children

CONTEXT

The first degree relatives of celiac patients represent a high risk group for the development of this disorder, so their screening may be crucial in the prevention of long-term complications.

OBJECTIVE

In order to determine the prevalence of celiac disease in a group of first degree relatives of children with proven gluten intolerance, we conducted a prospective study that consisted in the screening of celiac disease, using a capillary immunoassay rapid test that allows a qualitative detection of IgA antibody to human recombinant tissue transglutaminase (IgA-TTG).

METHODS

When the screening test was positive subjects were advised to proceed with further investigation. The screening test was performed in 268 first degree relatives (143 mothers, 89 fathers, 36 siblings) corresponding to 163 children with celiac disease.

RESULTS

Screening test was positive in 12 relatives (4.5%), of which 1 refused to continue the investigation. In the remaining 11 relatives celiac disease was diagnosed in 7 cases (2.6%, 5 mothers, 2 fathers) who had a median age of 39 years (27-56 years), mild gastrointestinal symptoms, high titre of IgA-TTG and histology abnormalities confirming the diagnosis. All these patients are currently on a gluten-free diet.

CONCLUSION

The prevalence of celiac disease among first degree relatives (2.6%) was 5 times higher than that in the general population. Although the recommendations for screening asymptomatic high risk groups, such as first degree relatives, are not unanimous the early diagnosis is crucial in preventing complications, including nutritional deficiency and cancer.

Prevalence of celiac disease among first-degree relatives of patients with celiac disease

OBJECTIVES

Celiac disease, an autoimmune enteropathy that affects the proximal small intestine, is characteristically seen in people who have a genetic susceptibility to gluten sensitivity. Celiac patients' first-degree relatives are more at risk of acquiring the disease. The objective of the present study was consequently to determine the prevalence of celiac disease in a group of first-degree relatives of our patients with celiac disease.

METHODS

First-degree relatives of 195 patients with celiac disease attending a gastroenterology unit underwent serologic screening. Antitissue transglutaminase (anti-tTG) immunoglobulin A (IgA) and total serum IgA tests were used for first-level screening. Duodenal biopsy was recommended to subjects showing positive results to anti-tTG IgA testing. Biopsy samples were obtained by endoscopy, and biopsy specimens were evaluated and classified according to Marsh classification.

RESULTS

Positive anti-tTG IgA was found in 46 first-degree relatives (9.5%), whereas serum IgA levels were normal. Of 46 serology-positive relatives, 34 agreed to the endoscopy procedure. Histological changes characteristic of celiac disease were found in 23 subjects. The prevalence of celiac disease among the first-degree relatives was found to be at least 4.8%. Of 34 subjects that underwent biopsy, 11 were evaluated as Marsh 0, 5 as Marsh 1, 4 as Marsh 2, 12 as Marsh 3, and 2 as Marsh 4. Of the biopsy-positive subjects, 3 were mothers, 1 was a father, and 19 were siblings.

CONCLUSIONS

The present study identified 23 undiagnosed cases of celiac disease among 484 first-degree relatives of 195 patients with celiac disease, confirming the high prevalence (4.8%) of the disease in this specific group. It is suggested that an extensive screening policy be mandatory for these subjects.

Serologic screening and genetic testing among brazilian patients with celiac disease and their first degree relatives

CONTEXT

Celiac disease susceptibility has been shown to be associated with the HLA alleles DQA1*0501 and DQB1*0201 (together encoding the DQ2 heterodimer) that are present in practically all celiac disease patients. The DQ8 heterodimer (coded by DQA1*03-DQB1*0302), which is carried on a DRB1*04 (DR4) haplotype, is commonly encoded for by the few celiacs who do not carry the DQ2 heterodimer. Only a few celiac disease patients have been reported without these known risk alleles.

OBJECTIVE

To assess the prevalence of celiac disease in a group of first degree relatives of celiac patients, and the frequency of HLA predisposing alleles both in the group of celiac patients and in their first degree relatives, identifying those first degree relatives who would need further screening for celiac disease.

METHODS

Ninety celiac disease patients and 207 first degree relatives underwent serologic screening for celiac disease (endomysial and transglutaminase antibodies) followed by intestinal biopsy in positive patients. The HLA-DQA1*0501, DQB1*0201 and DRB1*04 frequencies of celiac patients and their first degree relatives were determined utilizing the PCR method.

RESULTS

All the celiac disease patients (n = 90) with the exception of one (1.1%) carried at least one of the alleles investigated. Altogether 11 (5.3%) of the investigated first degree relatives did not carry any of the alleles studied. Fourteen (6.7%) new cases of celiac disease were found among the 207 celiac disease patients first degree relatives.

CONCLUSIONS

Considering the cost-benefit of the HLA typing of all the first degree relatives of celiac patients, their HLA status should be decided on an individual basis, taking account of their profile and preferences, and the existence of other medical conditions.

Prevalence, human leukocyte antigen typing and strategy for screening among Asian first-degree relatives of children with celiac disease

BACKGROUND AND AIM

Data on prevalence, human leukocyte antigen (HLA) typing and small bowel histology among first-degree relatives of subjects with celiac disease (CD) is scarce. This prospective study evaluated the prevalence and role of HLA DQ2/8 testing in screening of first-degree relatives of children with CD.

METHODS

Thirty confirmed children with CD and 91/94 first-degree relatives (parents and siblings) were enrolled. HLA DQ2/8 testing was carried out in all index CD cases. Clinical evaluation with a questionnaire, total serum immunoglobulin A (IgA), human IgA-tissue transglutaminase (IgA-tTGA) and HLA DQ2/8 testing was carried out in all first-degree relatives. Subjects who were positive for IgA-tTGA were recommended endoscopic duodenal biopsy to document histological changes of CD.

RESULTS

Nine first-degree relatives were positive for IgA-tTGA, seven underwent duodenal biopsy and four subjects had Marsh IIIa changes suggestive of CD. The prevalence of histologically confirmed CD in first-degree relatives was 4.4%. The prevalence of potential CD was 9.8%. IgA-tTGA-positive subjects (4/9) were significantly more often symptomatic than IgA-tTGA-negative first-degree relatives (2/82). Twenty-nine (96.6%) index cases of CD and all IgA-tTGA-positive first-degree relatives were positive for HLA DQ2. None of the index CD cases or first-degree relatives were HLA DQ8-positive. A total of 85% of the first-degree relatives were positive for HLA DQ2 and thus at risk of developing CD.

CONCLUSIONS

In this first Asian study on a limited number of families of children with CD, 4.4% of the first-degree relatives had CD. Only 15% of the first-degree relatives were negative for HLA DQ2/DQ8. Initial evaluation with HLA and serology followed by only serial serology in HLA-positive relatives is recommended.

Influence of previously ingested wheat on fasting breath hydrogen in celiac patients

The excretion of hydrogen in breath commonly persists, despite an overnight fast. Although the elevation of hydrogen concentration above the fasting value after the administration of a test sugar is evidence of malabsorption, the level of the fasting value itself in untreated celiac patients is unknown. Therefore, we studied the fasting breath hydrogen (FBH(2)) concentration in 40 healthy controls, 35 subjects with functional bowel disorders, and 30 patients of untreated celiac disease with and without bread or wheat diet one day before the test. The fasting level of hydrogen concentration in untreated celiac patients (28.7 +/- 19.5 ppm) was significantly higher than those in healthy volunteers (9.5 +/- 3.4 ppm) and subjects with functional bowel disorders (10.6 +/- 4.5 ppm). The percentage of patients with elevated H(2) fasting levels in untreated celiac disease (82.5%) was significantly higher than that in healthy controls (10%) and subjects with functional bowel disorders (17.1%). In 30 celiac patients, studied with and without wheat-free diet one day before the test, the fasting hydrogen levels decreased from 28.7 +/- 19.5 ppm to 10.6 +/- 3.5 ppm, and becoming normal in all patients of celiac disease. Our results show that the patients of untreated celiac disease should be instructed not to eat things made up of wheat one day before hydrogen breath testing so that the normal fasting hydrogen concentration can be obtained and false-negative hydrogen breath test results can be avoided.