Serological markers and HLA genes among healthy first-degree relatives of patients with coeliac disease

Coeliac disease: Evaluation of diagnosis in children and teenagers

BACKGROUND

Coeliac disease is no longer a rare disease, but has a rising prevalence, especially in children, with a shift from malabsorption syndrome to a more subtle presentation. Therefore, European guidelines regarding the diagnosis of coeliac disease were changed in 2012. If laboratory tests are positive, children can now be diagnosed without performing an endoscopy. The aim of this study was to characterize the Swiss patients, who have been diagnosed with coeliac disease.

METHODS

This is a retrospective study of Swiss paediatric patients who have been diagnosed with coeliac disease according to European guidelines between 01/2011 and 11/2020. The data needed was extracted from medical records.

RESULTS

A total of 369 children were included in the study. The main complain was abdominal pain (118; 32%), followed by failure to thrive/gain weight (92; 24.9%). 10% (37/367) of all patients had no symptoms at all. In 72.6% (268/369) of all patients, an endoscopy was performed due to lower antibodies. Mean values for ferritin, vitamins D and B₁₂ as well as folic acid were within normal range.

CONCLUSION

In our cohort of patients, females were clearly more often affected and also showed a small deviation in height and weight. Our finding of 10% of all patients having no symptoms at all is in line with other studies observing a decline in symptoms. A complicating factor for the clinician is the fact that overall no vitamin deficiencies were detected. As the incidence continues to rise but the clinical presentation of coeliac disease is changing from a malabsorption syndrome to a silent disease, further observational studies are needed to monitor this trend.

The Gluten-Free Diet for Celiac Disease and Beyond

The gluten-free diet (GFD) has gained popularity beyond its main medical indication as the treatment for gluten-induced immune-mediated disorders such as celiac disease (CD), dermatitis herpetiformis, gluten ataxia, wheat allergy, and non-celiac gluten sensitivity. However, the diet carries some disadvantages such as elevated costs, nutritional deficiencies, and social and psychological barriers. The present work aims to review indications, proven benefits, and adverse events of a gluten-free diet. Close follow-up with patients following the diet is recommended. More data is needed to assess the effectiveness of the diet in managing mental and cognitive disorders and to establish a connection between the brain and gluten.

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.

Gluten-Induced Extra-Intestinal Manifestations in Potential Celiac Disease-Celiac Trait

Celiac disease patients may suffer from a number of extra-intestinal diseases related to long-term gluten ingestion. The diagnosis of celiac disease is based on the presence of a manifest small intestinal mucosal lesion. Individuals with a normal biopsy but an increased risk of developing celiac disease are referred to as potential celiac disease patients. However, these patients are not treated. This review highlights that patients with normal biopsies may suffer from the same extra-intestinal gluten-induced complications before the disease manifests at the intestinal level. We discuss diagnostic markers revealing true potential celiac disease. The evidence-based medical literature shows that these potential patients, who are “excluded” for celiac disease would in fact benefit from gluten-free diets. The question is why wait for an end-stage disease to occur when it can be prevented? We utilize research on dermatitis herpetiformis, which is a model disease in which a gluten-induced entity erupts in the skin irrespective of the state of the small intestinal mucosal morphology. Furthermore, gluten ataxia can be categorized as its own entity. The other extra-intestinal manifestations occurring in celiac disease are also found at the latent disease stage. Consequently, patients with celiac traits should be identified and treated.

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.

Prevalence of serum celiac antibodies in a multiracial Asian population--a first study in the young Asian adult population of Malaysia

Background

Celiac disease (CD) is an immune-mediated disorder induced by the ingestion of gluten in genetically susceptible persons. The prevalence of CD in Malaysia is unknown. We aim to determine the seroprevalence of CD antibodies and also investigate the correlation between H. pylori infection and CD in the young and healthy multiracial Malaysian population.

Methods

Healthy young adult volunteers between the ages of 18–30 years were consecutively recruited from June 2012 to May 2014 at the University of Malaya Medical Centre (UMMC), Kuala Lumpur. Serum samples from all the participants were tested for anti-gliadin antibody immunoglobulin A/immunoglobulin G (IgA/IgG) and anti-tissue transglutaminase antibody (tTG) IgA/IgG. Samples positive for both anti-gliadin and anti-tTG were further validated for anti-human endomysial IgA antibodies (EmA). Serological diagnosis of CD was made when anti-gliadin, anti-tTG and anti-EmA were positive.

Results

562 qualified participants with mean age 24 ± 2.4 years old were recruited into our study. CD was found in 7 participants where most of them were asymptomatic and unaware of their CD status. The median of anti-gliadin and anti-tTG IgA/IgG value was 38.2 U/ml (interquartile range, 28.3–60.4 U/ml) and 49.2 U/ml (interquartile range, 41.1–65.9 U/ml), respectively. Seroprevalence of CD antibodies was 1.9% (6 out of 324) in female while only 0.4% (1 out of 238) in male. Seroprevalence among Malay was 0.8% (2 of 236), Chinese was 1.7% (3 of 177) and Indian was 1.3% (2 of 149). Overall, seroprevalence of CD antibodies in healthy asymptomatic adults in the Malaysian population was 1.25% (95% CI, 0.78%-1.72%). No significant relationship was discovered between CD and H. pylori infection.

Conclusions

The seroprevalence of CD antibodies in healthy young adults in the Malaysian population was 1.25% (1 in 100). CD is underdiagnosed and it could be a much greater problem in Malaysia than previously thought.

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.

Serum markers in the clinical management of celiac disease

The advent of highly reliable noninvasive celiac diagnostic tests has transformed the field of celiac disease, from diagnosis, to evaluation of epidemiology, to clinical and translational research. Serologic tests in their modern forms are highly sensitive and specific for diagnosis, allowing for consideration of avoidance of diagnostic intestinal biopsy in some settings. On the other hand, as predictors of intestinal damage and for use in monitoring disease activity, currently available noninvasive tests have been disappointing. Serologic tests, while a measure of disease activity, do not correlate well with histology or symptomatology, and it is unclear if they predict long-term risk. Additionally, while the many clinically available tests have improved accessibility, they can have widely different cutoff levels and overall performance, making the comparison of levels in individual patients over time and across populations quite difficult. In the future, we can expect to see improvement in the currently available serologic tests including tissue transglutaminase and deamidated gliadin peptide with expansion of the dynamic range of the tests, and the celiac care community should push for a standardization of assays that would simplify research and patient care. Additionally, current serologic tests are measures of the adaptive immune response in celiac disease but do not directly measure intestinal inflammation. Promising work on intestinal fatty acid-binding protein and other assays which directly measure intestinal damage may complement traditional serologic tests and further improve our ability to noninvasively diagnose and monitor celiac disease. The coming years hold promise for the continuing evolution of serum-based tests in celiac disease with the possibility of substantial improvement of patient care and clinical research.

Early microbial markers of celiac disease

BACKGROUND AND GOALS

Seroreactivity against the Saccharomyces cerevisiae (ASCA), Pseudomonas fluorescens-associated sequence (I2), and Bacteroides caccae TonB-linked outer membrane protein (OmpW) has been detected in celiac disease patients with small-bowel mucosal atrophy. Levels of these antibodies decrease during a gluten-free diet, but their functions and time of appearance in celiac disease are not known. We aimed to search for evidence of possible microbial targets of the immune responses in the early-stage celiac disease patients who showed normal small-bowel mucosal architecture at the time of the first investigations, but later on a gluten-containing diet developed mucosal atrophy.

MATERIALS AND METHODS

Forty-four cases with proven early-stage celiac disease and normal mucosal morphology were enrolled. Patients' sera were tested for celiac disease antibodies against tissue transglutaminase (tTG-ab), endomysium, and for microbial antibodies against I2, OmpW, and ASCA IgG and IgA isotypes in both at the time of diagnosis and while on a gluten-free diet.

RESULTS

Thirty-four (77%) of 44 patients with early-stage celiac disease had elevated serum antibodies to one or more of the antibodies ASCA, I2, and OmpW. Furthermore, 5 of 6 cases negative for both tTG-ab and endomysium showed positivity for the microbial markers. Seroreactivity to ASCA IgA, ASCA IgG, and OmpW decreased significantly during gluten-free diet.

CONCLUSIONS

Seroreactivity to different microbial antigens is evident already in patients with early-stage celiac disease. ASCA antibodies seem to be gluten-dependent. The results indicate that the microbial targets might have a role in the early development of celiac disease.

Prevalence of serum celiac antibody in patients with IBD in Japan

BACKGROUND

Although the incidence of inflammatory bowel diseases (IBD) in Japan has increased, the prevalence of celiac disease is considered very low with the lowest genetic disposition. IBD is reported as the most common comorbidity because of the high positive rate of serological celiac markers. The aim of this study was to examine the current incidence of celiac disease, especially in IBD patients in Japan, where both wheat consumption and incidence of IBD have increased.

METHODS

A total of 172 patients with IBD and 190 controls in Japan were screened for serum antibody of tissue transglutaminase and deaminated gliadin peptide. In sero-positive patients, HLA testing and upper gastrointestinal endoscopy with duodenal biopsy was performed. Some of the sero-positive patients started a gluten-restricted or unrestricted diet, and serological change was determined.

RESULTS

The positivity of both serum antibodies was significantly higher in IBD and correlated with disease activity. However, no biopsy-defined or HLA-defined true celiac disease was found. A decrease in serum antibody titers was observed with a gluten-restricted diet.

CONCLUSIONS

Despite the increased incidence of IBD and high positivity for serum celiac antibody in Japanese IBD patients, no true-positive celiac disease was noted, suggesting the presence of gluten intolerance in these populations.

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.

Anti-TCR gamma antibody in celiac disease: the value of count on formalin-fixed paraffin-embedded biopsies

Small bowel intraepithelial lymphocytosis (IL) may depend from different causes, including celiac disease (CD). Demonstration of increased number of duodenal T cell receptor gamma-delta (TCRγδ) positive intraepithelial lymphocytes (IELs) has been used to support CD diagnosis on frozen material. This work evaluates a new commercially available anti-TCRγ antibody on formalin-fixed paraffin embedded (FFPE) small bowel biopsies. Anti-CD3 and anti-TCR CγM1 (clone γ3.20) from Thermo Scientific were applied by immunohistochemistry on 59 FFPE biopsies from 18 cases of CD with mild/severe atrophy, 19 cases of IL in CD patients on gluten-free diet (IL-GFD), 14 cases of IL (6/14 with positive CD-related serology), and 8 controls (CTR) with mild duodenitis and negative CD serology and genotyping. IELs/100 epithelial cells were counted in at least six high power fields. CD3+ and TCRγ+ IELs were significantly higher in CD, IL-GFD, and IL compared with CTR, but in contrast to CD3+ IELs, TCRγ+ IELs were significantly increased in CD and IL-GFD compared with IL. Furthermore, TCRγ+ IELs discriminated between IL with negative and positive CD-related serology (p = 0.02). TCRγ+ IELs can be identified on FFPE samples and their evaluation adds useful information for the work-up of small bowel biopsies in CD diagnosis. In fact, TCRγ staining coupled with CD3, may represent an additional tool to recognize cases of latent/potential CD when serology and clinical data are not conclusive or when the histological diagnosis remains equivocal.

Fingertip rapid point-of-care test in adult case-finding in coeliac disease

BACKGROUND

Coeliac disease (CD), due to its protean clinical manifestation, is still very under diagnosed in adults and delays in diagnosis may take years and even decades. Simple tools to find cases in primary care may help to identify patients for further diagnostic tests. We have evaluated the usefulness of an on site rapid fingertip whole blood point-of-care test (POCT) for such a purpose.

METHODS

As CD is known to run within families, we tested 148 healthy relatives of 70 Romanian index cases with biopsy-proven CD (87% of all first-degree family members, median age 36 years) for the presence of circulating autoantibodies. In addition to performing the POCT (which measures blood erythrocyte self-TG2-autoantibody complexes) on site, blood was drawn for later evaluations of serum IgA-class endomysial antibodies (EMA). EMA-positive sera were further tested for transglutaminase 2 antibodies (TG2-IgA). All serological parameters were analyzed blindly in a centralized laboratory that had no knowledge of the on site POCT result. Endoscopic small intestinal biopsies was recommended for all POCT- or EMA-test positive subjects.

RESULTS

In on site testing the POCT was positive in 12/148 first-degree relatives (8%) and all these subjects were also serum EMA-positive. A positive EMA test was found only in one other subject. All remaining 135 healthy first-degree relatives were negative for both POCT and EMA. Four subjects positive for both POCT and EMA were negative for TG2-IgA. Ten out of thirteen of the antibody-positive subjects agreed to undergo endoscopy. The POCT was found to be positive in 8/9 first-degree relatives having coeliac-type mucosal lesions of grade Marsh 2 (n = 3) or Marsh 3 (n = 6). The three POCT-positive subjects not agreeing to undergo endoscopy were also both EMA- and TG2-IgA-positive.

CONCLUSION

The fingertip whole blood rapid POCT might fulfill the unmet need for a simple and cheap case-finding biomarker for early detection and presumptive diagnosis of CD. Confirmatory studies are warranted in adult case-finding in specialized outpatient clinics and in primary care.

An update on celiac disease histopathology and the road ahead

CONTEXT

Celiac disease (CD) is a common immune-mediated disorder that occurs in genetically predisposed individuals (carriers of HLA-DQ2 and DQ8 haplotypes) on consumption of wheat (gluten). It is characterized by inflammation of the small-intestinal mucosa and myriad gastrointestinal and systemic manifestations. Celiac disease is common in the general population (prevalence, 0.5%-1%). Currently, small-bowel biopsy is considered the gold standard for diagnosing CD. However, the role of serologic testing in the diagnosis of CD has evolved, from being a supportive test to supplanting intestinal biopsies in certain patient populations.

OBJECTIVE

To summarize key aspects of histopathologic assessment, discuss the benefit of standardized pathology reports, impact of the site and number of small-bowel biopsy samples on diagnosis, and recommendations regarding serologic testing.

DATA SOURCES

Literature review of publications on CD and experience with histopathologic review of biopsies at the Department of Pathology and Cell Biology, Columbia University Medical Center, New York-Presbyterian Hospital, New York.

CONCLUSIONS

Intraepithelial lymphocytosis in the context of villous atrophy is considered a characteristic histologic finding of CD; however, it is a rather nonspecific finding. A growing list of publications has also indicated that the detection of intraepithelial lymphocytosis in the absence of villous atrophy has rather low specificity for CD. Therefore, communication between pathologists and gastroenterologists is paramount, as is knowledge regarding the pertinent clinical and laboratory data, in distinguishing between CD and other disorders with similar histopathologic and clinical manifestations.

Utility of the new ESPGHAN criteria for the diagnosis of celiac disease in at-risk groups

OBJECTIVE

Demonstration of small-bowel mucosal damage has been the basis of celiac disease diagnosis, but the diagnostic approach is undergoing changes. The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition recently stated that in a subgroup of children, high positive transglutaminase 2 antibody (TG2ab) values may be sufficient for the diagnosis. The utility of these new criteria was evaluated by applying the human red blood cell TG2 antibody test (RBC-TG2ab) to a large cohort of children and adults belonging to at-risk groups.

METHODS

RBC-TG2ab and endomysial antibodies (EmA) were measured in 3031 family members or other relatives of patients with celiac disease. The RBC-TG2ab values were classified as weak (20-29 U), moderate (30-99 U), and strong (≥100 U) positive. Seropositive subjects were further tested by human recombinant TG2ab (Hr-TG2ab) and for the presence of celiac disease-associated human leukocyte antigen-DQ alleles. Gastroscopy was recommended for all with positive RBC-TG2ab, EmA, or Hr-TG2ab, or weak positive RBC-TG2ab and symptoms.

RESULTS

Strong positive RBC-TG2ab has good correlation with EmA and Hr-TG2ab and positivity of DQ2/8, and the diagnosis was established in 94% of both children and adults. In contrast, moderately positive (≥30 U) RBC-TG2ab showed poor correlation with the other tests, and celiac disease was diagnosed in 69% of children and 86% of adults. Most participants with weak positive RBC-TG2ab were negative for EmA and Hr-TG2ab.

CONCLUSIONS

In accordance with the new European Society for Pediatric Gastroenterology, Hepatology, and Nutrition criteria, strong positive RBC-TG2ab showed good accuracy and excellent correlation with the other antibodies and celiac-type human leukocyte antigen. In contrast, low or moderately positive RBC-TG2ab values were of unsatisfactory prognostic value for a subsequent diagnosis.

Ages of celiac disease: From changing environment to improved diagnostics

From the time of Gee’s landmark writings, the recent history of celiac disease (CD) can be divided into many ages, each driven by a diagnostic advance and a deeper knowledge of disease pathogenesis. At the same time, these advances were paralleled by the identification of new clinical patterns associated with CD and by a continuous redefinition of the prevalence of the disease in population. In the beginning, CD was considered a chronic indigestion, even if the causative food was not known; later, the disease was proven to depend on an intolerance to wheat gliadin, leading to typical mucosal changes in the gut and to a malabsorption syndrome. This knowledge led to curing the disease with a gluten-free diet. After the identification of antibodies to gluten (AGA) in the serum of patients and the identification of gluten-specific lymphocytes in the mucosa, CD was described as an immune disorder, resembling a chronic “gluten infection”. The use of serological testing for AGA allowed identification of the higher prevalence of this disorder, revealing atypical patterns of presentation. More recently, the characterization of autoantibodies to endomysium and to transglutaminase shifted the attention to a complex autoimmune pathogenesis and to the increased risk of developing autoimmune disorders in untreated CD. New diagnostic assays, based on molecular technologies, will introduce new changes, with the promise of better defining the spectrum of gluten reactivity and the real burden of gluten related-disorders in the population. Herein, we describe the different periods of CD experience, and further developments for the next celiac age will be proposed.

[Epidemiology of celiac disease]

Celiac disease is an autoimmune disorder induced by gluten in genetically susceptible individuals. Patients may present with typical symptoms of enteropathy with diarrhoea and failure to thrive, but atypical symptoms, or even silent forms are more often recognized since serologic markers are available. This progress led to the increase of the incidence of the celiac disease during the last 30 years, which reflect probably the improvement in diagnosing atypical forms of the disease. The prevalence is comparable from a country to another, around 0,7 to 2%. There is a progression with time from latent to silent form, and then to the active disease. The exclusion of the gluten from the diet leads to the regression from the active to the latent form of the disease.

Antibodies in celiac disease: implications beyond diagnostics

Celiac disease is a multisystemic dietary, gluten-induced autoimmune disorder characterized by the presence of transglutaminase (TG) 2 serum autoantibodies. Distinct autoantibodies targeting members of the TG family (TG2, TG3 and TG6) are found deposited in small-bowel mucosa and in extraintestinal tissues affected by the disease. Serum autoantibodies against other self-antigens also emerge in untreated celiac disease patients. Although villous atrophy and crypt hyperplasia in small-bowel biopsy samples are still the gold standards in diagnostics, celiac disease-specific antibodies are widely used as diagnostic aids. Gluten-induced small-bowel mucosal T-cell response is the cornerstone in the pathogenesis of the disorder, but humoral immunity may also play a central role. This review article is focused on the autoantibodies that occur in the context of celiac disease. The article summarizes the diagnostic utility of different celiac-related antibodies and discusses their roles in the pathogenesis of the disease.

Clinics of coeliac disease in children in the 2000s

OBJECTIVE

To describe the clinical picture of patients with coeliac disease (CD) and the change in its presentation over the past decades.

STUDY DESIGN

Patients with CD were identified and clinical data collected from hospital records over a 6-year period (2000-2005).

RESULTS

Altogether 197 patients aged 0.6-15.9 (mean 7.2) years were identified. They were found amongst the child population served by the hospital, the mean number of children at age 0.5-16 years was 268 000 during 2000-2005. The presenting symptom amongst the youngest patients (<3 years) was chronic diarrhoea (in 67%), and amongst older patients, abdominal pain. At the time of diagnosis, growth was severely retarded (height <2 SD for age) in 6.6%; mean height was -0.06 SD and weight + 1% for height. After diet treatment for a mean of 6 months, both height and weight increased significantly. Anaemia and iron deficiency were present in 25% and 43% of patients respectively. Intraepithelial T-cell receptor gamma/delta cells were pathologic in all 150 specimens studied.

CONCLUSIONS

The presentation of CD depends on age. Even when we found six times more patients than during years 1976-1985 in the same hospital, published data on the prevalence of CD suggest that we found only a small minority of children with CD.

Gastrointestinal symptoms, quality of life and bone mineral density in mild enteropathic coeliac disease: a prospective clinical trial

OBJECTIVE

The diagnosis of coeliac disease requires small-bowel mucosal villous atrophy with crypt hyperplasia. However, patients with endomysial antibodies but structurally normal villi may suffer from a disorder similar to those with villous atrophy. The aim of this study was to evaluate gastrointestinal symptoms, quality of life and bone mineral density in patients with mild enteropathy, and the effect of a gluten-free diet.

MATERIAL AND METHODS

A prospective trial was carried out in 73 adults having endomysial antibodies with normal villous morphology (Marsh I-II; mild enteropathy) or villous atrophy (Marsh III). Gastrointestinal symptoms and quality of life were surveyed by means of structured questionnaires and bone mineral density by means of X-ray absorptiometry. Altogether, 110 subjects served as non-coeliac controls.

RESULTS

At baseline, patients with mild enteropathy evinced more gastrointestinal symptoms than non-coeliac controls, but there were no significant differences in quality of life between the groups. After 1 year on a gluten-free diet, indigestion and depression were significantly alleviated in the mild enteropathy group. Osteoporosis or osteopenia was detected in 58% of subjects in the mild enteropathy group and there was a trend towards improved bone mineral density after the treatment.

CONCLUSIONS

Endomysial antibody-positive patients with normal villous structure may suffer from gastrointestinal symptoms and have poor bone health. Furthermore, they benefit from a gluten-free diet similar to those with overt villous atrophy.

Diagnosing mild enteropathy celiac disease: a randomized, controlled clinical study

BACKGROUND & AIMS

The diagnostic criteria for celiac disease require small-bowel mucosal villous atrophy with crypt hyperplasia (Marsh III). However, mucosal damage develops gradually and patients may evince clinical symptoms before histologic changes appear. Endomysial antibodies are specific in predicting forthcoming villous atrophy. We hypothesized that patients with mild enteropathy but positive endomysial antibodies benefit from a gluten-free diet (GFD) similarly to patients with more severe enteropathy.

METHODS

Small-bowel endoscopy together with clinical evaluations was performed in all together 70 consecutive adults with positive endomysial antibodies. Of these, 23 had only mild enteropathy (Marsh I-II) and they were randomized either to continue on a gluten-containing diet or start a GFD. After 1 year, clinical, serologic, and histologic evaluations were repeated. A total of 47 participants had small-bowel mucosal lesions compatible with celiac disease (Marsh III), and these served as disease controls.

RESULTS

In the gluten-containing diet group (Marsh I-II) the small-bowel mucosal villous architecture deteriorated in all participants, and the symptoms and abnormal antibody titers persisted. In contrast, in the GFD group (Marsh I-II) the symptoms were alleviated, antibody titers decreased, and mucosal inflammation diminished equally to celiac controls (Marsh III). When the trial was completed, all participants chose to continue on a life-long GFD.

CONCLUSIONS

Patients with endomysial antibodies benefit from a GFD regardless of the degree of enteropathy. The diagnostic criteria for celiac disease need re-evaluation: endomysial antibody positivity without atrophy belongs to the spectrum of genetic gluten intolerance, and warrants dietary treatment.

HLA and autoimmune digestive disease: a clinically oriented review for gastroenterologists

OBJECTIVES

The human leukocyte antigen (HLA) system includes genes involved in graft-vs-host rejection and in immune response. The discovery that HLAs are associated with several diseases led to appealing developments both in basic biomedical research and in clinical medicine, and offered the opportunity to improve the understanding of pathogenesis and classification of diseases, as well as to provide diagnostic and prognostic indicators. The aim of this article is to review the association between HLA alleles and autoimmune digestive disease and its current relationship with modern HLA nomenclature and clinical practice.

METHODS

Articles dealing with the association between HLAs and autoimmune digestive disease (including celiac disease, inflammatory bowel disease, autoimmune hepatitis, sclerosing cholangitis and primary biliary cirrhosis) were searched for using Pubmed and SCOPUS databases from earliest records to January 2008.

RESULTS

The review has provided two sections. In the first, we explain the basic principles of HLA structure, function, and nomenclature, as an introduction to the second section, which describes current associations between HLA alleles and digestive diseases. The clinical implications of each HLA association are critically discussed. Actually, a clinical role for HLA typing is suggested for only a few conditions, e.g., celiac disease.

CONCLUSIONS

The knowledge of current HLA nomenclature and of its association with some digestive diseases such as celiac disease can be useful in clinical practice for diagnostic and prognostic purposes. This can avoid improper HLA typing as well as stressing the need for further studies on other possible clinical applications.

Prevalence of celiac disease in Iranian children with idiopathic short stature

AIM: To determine the prevalence of celiac disease (CD) in children with idiopathic short stature (ISS) and the diagnostic value of immunoglobulin (Ig) A G antigliadin antibodies (AGA) and transglutaminase (TTG) antibodies for CD.

METHODS: A total of 104 children (49 male, 55 female) with ISS without a specific etiology were studied. Extensive endocrine investigations had shown no abnormalities in any subject. Anthropometric parameters and IgA AGA and IgA TTG antibodies were evaluated in this study group. These antibodies were measured by enzyme-linked immunosorbent assay. All patients were referred for an endoscopic intestinal biopsy. The biopsy samples were classified according to revised Marsh criteria (UEGW 2001).

RESULTS: We detected positive IgA TTG antibodies in 36 and IgA AGA in 35 of these patients. Thirty one IgA TTG antibody positive and 28 IgA AGA positive subjects showed histological abnormalities compatible with celiac disease (33.6%). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value for IgA AGA were found to be 80%, 88.4%, 77.8% and 89.7%, respectively. Sensitivity, specificity and PPV for IgA TTG antibodies were 88.6%, 94.2% and 88.6%, respectively.

CONCLUSION: We conclude that the prevalence of celiac disease is high in patients with ISS and it is important to test all children with ISS for celiac disease by measuring serologic markers and performing an intestinal biopsy.

Prevalence of celiac disease in Shiraz, southern Iran

BACKGROUND/AIM

This study was performed to evaluate the prevalence of celiac disease (CD) in Shiraz, southern Iran.

MATERIALS AND METHODS

Serum samples were collected from 1440 persons (age range = 20-83 years, mean age = 45.4 years) in 2004 and screened for endomysial and tissue transglutaminase antibodies. A questionnaire was completed for all subjects in relation to gastrointestinal (GI) symptoms and cases with positive serology were requested to undergo small-bowel biopsy.

RESULTS

Seven cases (0.5%) were positive for IgA anti-tissue transglutaminase (anti-tTG), and only two (0.14%) were positive for IgA anti-endomysial antibody (anti-EMA), both of whom had highly positive anti-tTg levels (40.4 and 48.0 IU/l). The major clinical symptoms of CD, such as recurrent abdominal pain and change in bowel habits were present in all patients with positive anti-tTG assays. Only five subjects with positive serology agreed to undergo upper GI endoscopy and duodenal biopsy. Three of these cases were reported with Marsh I histologic findings, while in the two cases with positive serologic anti-EMA, more advanced forms of CD were present.

CONCLUSION

The prevalence of CD in apparently healthy adults was lower than the reported series from northern parts of the country; therefore, we suggest a more long-term follow-up study in high-risk groups, especially in the apparently healthy subjects in our region.

Increasing prevalence of coeliac disease over time

BACKGROUND

The number of coeliac disease diagnoses has increased in the recent past and according to screening studies, the total prevalence of the disorder is around 1%.

AIM

To establish whether the increased number of coeliac disease cases reflects a true rise in disease frequency.

METHODS

The total prevalence of coeliac disease was determined in two population-based samples representing the Finnish adult population in 1978-80 and 2000-01 and comprising 8000 and 8028 individuals, respectively. Both clinically-diagnosed coeliac disease patients and previously unrecognized cases identified by serum endomysial antibodies were taken into account.

RESULTS

Only two (clinical prevalence of 0.03%) patients had been diagnosed on clinical grounds in 1978-80, in contrast to 32 (0.52%) in 2000-01. The prevalence of earlier unrecognized cases increased statistically significantly from 1.03% to 1.47% during the same period. This yields a total prevalence of coeliac disease of 1.05% in 1978-80 and 1.99% in 2000-01.

CONCLUSIONS

The total prevalence of coeliac disease seems to have doubled in Finland during the last two decades, and the increase cannot be attributed to the better detection rate. The environmental factors responsible for the increasing prevalence of the disorder are issues for further studies.

Recent advances in the understanding of celiac disease: therapeutic implications for the management of pediatric patients

Celiac disease (CD) is an autoimmune condition occurring in genetically susceptible individuals characterized by inflammatory injury to the mucosa of the small intestine after the ingestion of wheat glutens or related barley and rye products. Originally thought to be highly prevalent only in Northern European populations, growing evidence indicates a much higher prevalence in many other regions, including the US as well as South America, North Africa, and Asia. The growing awareness that pediatric patients may present with quite diverse and protean manifestations and the significant impact of CD on childhood development has prompted efforts to increase CD awareness for the early diagnosis and treatment of this disease. The current diagnostic criteria for CD requires characteristic histologic findings in small bowel biopsies and clinical remission when placed on a gluten-free diet. Serologic testing for CD can provide additional support for the diagnosis of CD or a means to assess efficacy and adherence to a gluten-free diet. The mainstay of treatment remains the institution of a gluten-free diet. However, patients with refractory CD may require treatment with immunosuppressant medications. With the increased identification of specific gluten epitopes and understanding of the pathogenesis of CD, future therapies may rely on genetically altering gluten proteins, immunization techniques, or therapies focused on either the development of specific immune tolerance or regulation of mucosal inflammation.

Duodenal intraepithelial lymphocytosis during Helicobacter pylori infection is reduced by antibiotic treatment

AIM

To evaluate clinical, biological and immunological features of patients with increased duodenal intraepithelial lymphocytes (IELs), and its relation to Helicobacter pylori (HP) and coeliac disease (CD).

METHODS

We have studied all patients accrued over a 4-year period with increased duodenal IELs. Those patients were recalled for biological and immunological evaluation and a second endoscopy.

RESULTS

Twenty-three from a total of 639 patients were identified and 17 of them were included in the study. The median duodenal IEL count was 59 per 100 epithelial cells. Twelve (71%) patients were HP+; eight of them received HP eradication. At the second endoscopy the duodenal IEL count was significantly lower 2 months after HP eradication (73 versus 28), while the IEL count was unchanged in those patients seronegative for HP (n = 5) or those in whom it was not eradicated (n = 4) (55 versus 55). No patient had coeliac antibodies, four expressed HLA-DQ2, lower than in the general population, and the prevalence of CD was 2% (12/639 patients).

CONCLUSION

In some cases an increased duodenal IEL count may be due to an inappropriate host response to HP. HP screening and eradication should be considered before recommending a gluten-free diet.

Prevalence and clinical significance of immunoglobulin A antibodies against tissue transglutaminase in patients with diverse chronic liver diseases

The prevalence of celiac disease (CD) and the prevalence and clinical significance of anti-tissue transglutaminase (tTG) antibodies (tTGAbs) in a large series of patients with chronic liver diseases were assessed. We studied 738 patients (462 with chronic viral hepatitis, 117 with autoimmune liver diseases, 113 with alcoholic or nonalcoholic fatty liver disease, and 46 with other liver disorders) and 1,350 healthy controls (HC). Immunoglobulin A (IgA) tTGAbs were measured by enzyme-linked immunosorbent assay and a microsphere-based flow cytometric assay. Positive sera were investigated for IgA antiendomysial antibodies (EmA). IgA tTGAb-positive subjects were invited to undergo a small-intestinal biopsy and HLA-DQ allele typing. Four of 1,350 HC (0.3%) tested tTGAb(+) EmA(+) and underwent a biopsy (CD confirmation in all). Four of 738 liver disease patients tested tTGAbs(+) EmA(+) (0.54%; not statistically significant). Two were HCV infected (1.24%; not statistically significant), and two had transaminasemia of unknown origin. Forty-three patients tested tTGAbs(+) EmA(-) (5.8%; P<0.001 compared to HC). Inhibition experiments verified the existence of specific IgA anti-tTG reactivity. Twenty-six of 43 patients underwent a biopsy (all negative for CD). Binary logistic regression analysis revealed age (P=0.008), cirrhosis (P=0.004), alkaline phosphatase (P=0.026), and antinuclear antibodies (P=0.012) as independent risk factors for tTGAb reactivity among the patients. It was concluded that CD prevalence is the same in HC and patients with chronic liver diseases. The prevalence of tTGAbs is higher in hepatic patients compared to HC, but their specificity for CD diagnosis in this group of patients is low. tTGAbs in patients appear to be associated with the presence of autoimmunity, cirrhosis, and cholestasis, irrespective of the origin of the liver disease.

Clinical, HLA, and small bowel immunohistochemical features of children with positive serum antiendomysium antibodies and architecturally normal small intestinal mucosa

BACKGROUND

Antiendomysium antibodies have a high sensitivity and specificity for celiac disease. A small percentage of subjects positive for these antibodies have a small intestinal mucosa hitherto considered normal.

OBJECTIVES

The aim of this study was to characterize the clinical, serological, immunogenetic, and immunohistological features of these subjects.

METHODS

From 409 patients who were positive for celiac-related antibodies, we selected 24 (5.9%) patients who had an architecturally normal small intestinal mucosa. One hundred age-matched celiac patients with a "flat" small intestinal mucosa, and 50 age-matched nonceliac children were also studied. The number of CD3+ and gammadelta+ intraepithelial lymphocytes and of CD25+ lamina propria mononuclear cells, and the expression of crypt HLA-DR and lamina propria ICAM-1 were assessed. HLA haplotyping was also performed.

RESULTS

Eleven (45.8%) of the 24 patients had a distinct infiltrative pattern, i.e., an increase in CD3+ intraepithelial lymphocytes (> 2SD of the nonceliac group), whereas 17 (70.8%) had a higher density of intraepithelial gammadelta+ cells. In 17 (70.8%) patients, the number of lamina propria CD25+ cells was increased and/or the expression of ICAM-1 and crypt HLA-DR was enhanced. All 24 patients carried the celiac disease-associated HLA haplotypes. Two of the six patients who remained on a normal diet and underwent a second jejunal biopsy developed villous atrophy.

CONCLUSIONS

Most of the patients with serum antiendomysium antibodies and normal jejunal histology showed immunohistochemical signs of immune activation in the epithelium, lamina propria, and crypts. We recommend that such patients be monitored to assess their progress and to determine whether they need a gluten-free diet.

CARD15 polymorphisms are associated with anti-Saccharomyces cerevisiae antibodies in caucasian Crohn's disease patients

Carriage of CARD15 gene polymorphisms and the serological marker anti-Saccharomyces cerevisiae antibodies (ASCA) are two markers for Crohn's disease (CD). Similar phenotypes have been associated with both markers. In the present study we analysed whether both markers were associated with each other and, if so, whether this association could be explained by a direct link or by an indirect association with those phenotypes. Therefore, we included 156 consecutive Caucasian CD patients and assessed the prevalence of the three common single nucleotide polymorphisms in the CARD15 gene. Serum samples were analysed for IgA and IgG ASCA by ELISA. CD patients with CARD15 polymorphisms were more frequently ASCA positive (OR 2.7 (1.4-5.2); P = 0.002) and had higher titres for ASCA IgA (P = 0.005) and ASCA IgG (P < 0.001) compared to patients carrying the wild type polymorphisms. Multivariate analysis demonstrated that this association was independent from ileal disease, penetrating disease and stricturing disease, the need for resective bowel surgery, familial cases, smoking habits and early age at onset. Homozygotes or compound heterozygotes for CARD15 polymorphisms had significantly more frequent ASCA positivity compared to single heterozygotes (OR 9.1 (1.1-74.2), P(c) (corrected P-value) = 0.030). These data indicate that there is a significant association between the carriage of CARD15 polymorphisms and ASCA, independent of the described phenotypes. Moreover, ASCA positivity is more frequent in CD patients carrying 2 CARD15 polymorphisms compared to single heterozygotes.

The prevalence of celiac disease in average-risk and at-risk Western European populations: a systematic review

Until recently, celiac disease (CD) was felt to be a rare disease in the United States. The aim of this study was to conduct a systematic review of the prevalence of CD in general Western populations and in populations at high risk for CD. Standard systematic review methodology was used. A literature search was conducted in MEDLINE (1966 to October 2003) and EMBASE (1974 to December 2003) databases. Qualitative and quantitative prevalence estimates were produced after assessing study heterogeneity. The prevalence of CD in general Western populations is close to 1% and is somewhat higher in certain Western European populations. The prevalence of CD in populations at risk for CD is as follows: 3%-6% in type 1 diabetic patients, up to 20% in first-degree relatives, 10%-15% in symptomatic iron-deficiency anemia (IDA), 3%-6% in asymptomatic IDA, and 1%-3% in osteoporosis. The prevalence of CD in patients suspected of having CD varied depending on the reasons for suspecting CD and on whether the study was conducted in a referral center. In general, the prevalence ranged from 5% to 15%, but was up to 50% in symptomatic patients evaluated in a tertiary referral center. CD is a common medical condition. The prevalence is higher still in high-risk groups. Clinicians in a variety of specialties should have a high index of suspicion for the diagnosis of CD and in particular need to pay close attention to the identified high-risk groups.

The diagnostic accuracy of serologic tests for celiac disease: a systematic review

Clinicians are increasingly utilizing noninvasive serologic tests for the diagnosis and screening of celiac disease (CD). The aim of this study was to conduct a systematic review of the diagnostic performance of serologic tests for the diagnosis and screening of CD. Standard systematic review methodology was used. A literature search was conducted in MEDLINE (1966 to October 2003) and EMBASE (1974 to December 2003) databases. A weighted mean of the sensitivity and specificity along with 95% confidence intervals and summary receiver operating characteristic (ROC) curves were calculated. The pooled specificity of endomyseal antibody (EMA)-monkey esophagus (ME) or EMA-human umbilical cord (HU) was close to 100% in adults and children. The pooled specificity of transglutaminase antibody (tTG)-guinea pig (GP) and tTG-human recombinant (HR) were between 95% and 99%. IgA-EMA-ME demonstrated sensitivities of 96% and 97% in children and adults, respectively. EMA-HU demonstrated a similar sensitivity of 97% in children but 90% in adults. The pooled sensitivity of tTG-GP in adults and children was 90% and 93%, respectively. The sensitivity of tTG-HR was 98% and 96%, respectively. The performance of antigliadin antibody was inferior to that of EMA and tTG. EMA and tTG offer high sensitivity and specificity. The sensitivity of these tests appears to be lower than reported when milder histologic grades are used to define CD (below 90%). If true, the nearly perfect negative predictive value of these tests would drop. The positive predictive value of these tests is likely lower than reported when the tests are applied in low-prevalence populations.

[Celiac disease in close family members]

OBJECTIVES

To investigate the presence of celiac disease (CD) in close family members of celiac patients, and the possible clinical differences between family members diagnosed and their respective index cases.

DESIGN

Descriptive, observational study based on a series of cases.

SETTING

Health centre and hospital.

PARTICIPANTS

Family members of celiac patients registered with the Association of Celiacs of Andalusia, based in Sevilla.

MAIN MEASUREMENTS

Patients and family members were interviewed and 2 questionnaires were filled in. The first, aimed at celiacs, recorded details of their disease and the second recorded personal details, current illnesses, personal history and the family members of all participants. IgA endomysium antibodies were determined only in family members.

RESULTS

56 of 215 families recorded took part, with 239 participants. Of the 56 patients, 1 per family, presentation at the moment of diagnosis was malabsorption syndrome. Of 165 family members studied, 11 cases with positive IgA endomysium antibodies were found and 5 actually with CD. One of these was asymptomatic, three presented with atypical forms of CD and another was diagnosed with herpetiform dermatitis.

CONCLUSIONS

That CD was most commonly found among close family members, along with its asymptomatic or atypical clinical presentation, justifies the active search for cases. Primary care doctors should question family members as to whether they have been tested for the disease. If not, adults should be checked for the antibodies referred to and children should be referred to their paediatricians for this purpose.

[Celiac disease in a group of children and adolescents with type 1 diabetes mellitus]

To know the prevalence of celiac disease (CD) in a group of children and adolescents with type I diabetes mellitus. A cross sectional study was conducted at the Instituto Materno Infantil de Pernambuco (IMIP) in March 2000. The sample consisted of 19 children and adolescents with type I diabetes mellitus that had the human anti-tissue transglutaminase antibodies assessed using kits from the Eurospital Laboratory. In case of positive results it was realized small intestine biopsy to confirm the diagnosis. For the calculation of the prevalence of CD it was considered the number of patients with serum positive histological alterations of the mucous membrane of the small intestine compatible with CD. Four patients presented serum positivity for human anti-tissue transglutaminase antibodies with a serum prevalence of 21% (4/19). Out of these four subjects, three who accomplished small intestine biopsy presented histological alterations compatible with CD. The prevalence of CD in this group was 15.8% (3/19). The prevalence of CD in this study group was high, suggesting that those with type I diabetes mellitus should be led as a group of high risk to develop this disease.

The risk of celiac disease in 107 families with at least two affected siblings

OBJECTIVES

Screening for celiac disease (CD) in the apparently healthy members of 107 nuclear families with two affected siblings (sib pair) and estimating the risk of CD in siblings and parents.

METHODS

One hundred seven families from Sweden and southern Norway with at least two affected children were investigated. Frozen sera from 187 of the 192 healthy parents and from 94 of 95 siblings without diagnosed CD were examined for total immunoglobulin A (IgA) and anti-endomysial antibodies (EMA). Individuals with positive antibody titers underwent small intestinal biopsy.

RESULTS

Positive test for EMA was found in 6 of 94 (6.3%) siblings without previously diagnosed CD and in 8 of 189 (4.2%) parents. CD was confirmed by small intestinal biopsy in all siblings and seven parents. The estimated risk for CD in multiply affected families was 26.3% for siblings and 12.9% for parents. An unexpected male preponderance was found among the new CD cases (10 males, 3 females).

CONCLUSION

The risk of CD in the members of nuclear families with two affected children is approximately three times higher than that when only one child is affected. The high male preponderance of new cases is unexpected and could not be explained fully by more silent disease in males as compared with females. Considering the high level of knowledge about CD in these families, the number of undiagnosed cases is surprisingly high. The authors suggest that serologic screening should be offered to all first-degree relatives of patients with CD.

Prevalence of Celiac disease among children in Finland

BACKGROUND

Wheat, rye, and barley proteins induce celiac disease, an autoimmune type of gastrointestinal disorder, in genetically susceptible persons. Because the disease may be underdiagnosed, we estimated the prevalence of the disease and tested the hypothesis that assays for serum autoantibodies can be used to detect untreated celiac disease and that positive findings correlate with specific HLA haplotypes.

METHODS

Serum samples were collected from 3654 students (age range, 7 to 16 years) in 1994 and screened in 2001 for endomysial and tissue transglutaminase antibodies. HLA typing was also performed on stored blood samples. All antibody-positive subjects were asked to undergo small-bowel biopsy in 2001.

RESULTS

Of the 3654 subjects, 56 (1.5 percent) had positive antibody tests, as determined in 2001. Results of the two antibody tests were highly concordant. As of 1994, none of the subjects had received a clinical diagnosis of celiac disease, but 10 who had positive tests for both antibodies in serum obtained in 1994 received the diagnosis between 1994 and 2001. Of the 36 other subjects with positive antibody assays who agreed to undergo biopsy in 2001, 27 had evidence of celiac disease on biopsy. Thus, the estimated biopsy-proved prevalence was 1 case in 99 children. All but two of the antibody-positive subjects had either the HLA-DQ2 or the HLA-DQ8 haplotype. The prevalence of the combination of antibody positivity and an HLA haplotype associated with celiac disease was 1 in 67.

CONCLUSIONS

The presence of serum tissue transglutaminase and endomysial autoantibodies is predictive of small-bowel abnormalities indicative of celiac disease. There is a good correlation between autoantibody positivity and specific HLA haplotypes. We estimate that the prevalence of celiac disease among Finnish schoolchildren is at least 1 case in 99 children.