Screening for asymptomatic celiac sprue in families

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.

Screening for celiac disease in family members: is follow-up testing necessary?

Celiac disease is a genetically determined intolerance to gluten that results in villous atrophy in the small intestine. Because celiac disease occurs in families, relatives of affected individuals are tested for the disease. However, there are no evidence-based guidelines for when, or how often, to test relatives. Our goal was to determine if one-time screening of relatives is sufficient. Of 171 family members with an initially negative endomysial antibody who were tested on more than one occasion, 6 (3.5%) were positive on repeat testing. The average time to seroconversion was 1.7+/-1.2 years (range, 6 months-3 years 2 months). Only one of the seroconverters had diarrhea; the remainder were asymptomatic. None of the patients had a change in symptoms between testing. We conclude that one-time testing for celiac disease among families with affected members is insufficient. Repeat testing should occur irrespective of the presence of symptoms.

Abnormal intestinal permeability in primary biliary cirrhosis

Antimitochondrial antibodies (AMAs) found in patients with primary biliary cirrhosis (PBC) cross-react with bacterial proteins and hence molecular mimicry has been proposed as a mechanism for AMA development. Alterations in gastrointestinal permeability would provide a potential route for increased exposure of gut flora to the immune system. In this study we aimed to compare the measured gastrointestinal permeability in patients with PBC to that in patients with liver disease (hepatitis C) and healthy control populations. Subjects drank a mixture of sucrose, lactulose, and mannitol dissolved in water. Eight-hour urinary excretion of the sugars was measured to assess intestinal permeability. Antiendomysial antibody testing was performed to exclude subclinical celiac disease. Eighty-six patients with PBC were evaluated and compared to 69 hepatitis C patients and 155 healthy controls. The mean urinary excretion of sucrose in the PBC patients (133.89 +/- 72.56 mg) was significantly higher than that in hepatitis C patients (101.07+/-63.35) or healthy controls (89.46+/-41.76) (P=0.0001), suggesting abnormal gastric or proximal small intestinal permeability. Sucrose excretion was not increased among patients with hepatitis C compared to healthy controls. The ratio of lactulose:mannitol excretion, reflecting small bowel permeability, was also elevated in the PBC group (0.017+/-0.012) compared to healthy controls (0.012+/-0.007) (P=0.0001) but was equal to that found among patients with hepatitis C (0.016+/-0.011) (P=NS). We conclude that the permeability of both the stomach and the small bowel is increased in patients with PBC, however, it is unclear if it is a cause, consequence, or manifestation of the disease.

Permeability, zonulin production, and enteropathy in dermatitis herpetiformis

BACKGROUND & AIMS

Dermatitis herpetiformis (DH) is characterized by variable degrees of enteropathy and increased intestinal permeability. Zonulin, a regulator of tight junctions, seems to play a key role in the altered intestinal permeability that characterizes the early phase of celiac disease. Our aim was to assess both intestinal permeability and serum zonulin levels in a group of patients with DH having variable grades of enteropathy.

METHODS

We studied 18 DH patients diagnosed on the basis of characteristic immunoglobulin (Ig)A granular deposits in the dermal papillae of noninvolved skin. Results were compared with those of classic celiac patients, patients with linear IgA dermatosis, and healthy controls.

RESULTS

According to Marsh's classification, 5 patients had no evidence of enteropathy (type 0), 4 patients had type II, 2 patients had type IIIb damage, and 7 patients had a more severe lesion (type IIIc). Intestinal permeability (lactulose/mannitol ratio [lac/man]) was abnormal in all patients with DH. Patients with more severe enteropathy had significantly greater permeability ( P < .05). The serum zonulin concentration (enzyme-linked immunosorbent assay) for patients with DH was 2.1 +/- .3 ng/mg with 14 of 16 (87.5%) patients having abnormally increased values. In contrast, patients with linear IgA dermatosis had normal histology, normal intestinal permeability, and negative celiac serology.

CONCLUSIONS

Increased intestinal permeability and zonulin up-regulation are common and concomitant findings among patients with DH, likely involved in pathogenesis. Increased permeability can be observed even in patients with no evidence of histologic damage in biopsy specimens. Patients with linear IgA dermatosis appear to be a distinct population with no evidence of gluten sensitivity.

Antiendomysium antibodies in Brazilian patients with celiac disease and their first-degree relatives

BACKGROUND

Literature data have shown high specificity of antiendomysial antibodies (EmA IgA) in celiac disease. The scarcity of Brazilian reports concerning this subject motivated the present study.

OBJECTIVES

To determine the sensitivity and specificity of antiendomysial IgA antibodies in Brazilian celiac patients at diagnosis and after treatment, to confirm patient adherence to a gluten-free diet and to screen first-degree relatives.

METHODS

An extensive clinical and serological study was performed by investigating the presence of these antibodies in 392 individuals from Southern Brazil. Indirect immunofluorescence using human umbilical cord as substrate was employed and the total levels of IgA were determined by turbidimetry in all groups. The study was conducted on 57 celiac patients (18 at diagnosis, 24 who adhered to a gluten-free diet and 15 with marked or slight transgression of the diet), 115 relatives of celiac patients (39 families), 94 patients with other gastrointestinal diseases, and 126 healthy individuals from the general population.

RESULTS

The results demonstrated 100% positivity for the recently diagnosed patients and for those consuming gluten, in contrast to the patients who complied with the diet (0%). In the control group one individual was positive, but refused to undergo a biopsy. In the group of other gastrointestinal diseases, one positive patient presented ulcerative colitis, Down's syndrome and epilepsy, and the intestinal biopsy was diagnostic for celiac disease. These data showed 99.3% specificity for the test. Eighteen relatives were positive for antiendomysial antibodies IgA (15.65%), and comparison with the healthy population revealed a significant difference. An intestinal biopsy was obtained from seven subjects (one with total villous atrophy and six without alterations in the mucosal architecture, but all with a high number of intra-epithelial lymphocytes).

CONCLUSIONS

The method revealed 100% sensitivity and 99.3% specificity. Because it is not an invasive method it can be used for the screening of atypical and latent forms of celiac disease to avoid serial biopsies and to control adherence to a gluten-free diet with implications in the prevention of malignancy in celiac disease.

Comparative evaluation of serologic tests for celiac disease: a European initiative toward standardization

BACKGROUND

Serologic methods have been used widely to test for celiac disease and have gained importance in diagnostic definition and in new epidemiologic findings. However, there is no standardization, and there are no reference protocols and materials.

METHODS

The European working group on Serological Screening for Celiac Disease has defined robust noncommercial test protocols for immunoglobulin (Ig)G and IgA gliadin antibodies and for IgA autoantibodies against endomysium and tissue transglutaminase. Standard curves were linear in the decisive range, and intra-assay variation coefficients were less than 5% to 10%. Calibration was performed with a group reference serum. Joint cutoff limits were used. Seven laboratories took part in the final collaborative study on 252 randomized sera classified by histology (103 pediatric and adult patients with active celiac disease, 89 disease control subjects, and 60 blood donors).

RESULTS

IgA autoantibodies against endomysium and tissue transglutaminase rendered superior sensitivity (90% and 93%, respectively) and specificity (99% and 95%, respectively) over IgA and IgG gliadin antibodies. Tissue transglutaminase antibody testing showed superior receiver operating characteristic performance compared with gliadin antibodies. The K values for interlaboratory reproducibility showed superiority for IgA endomysium (0.93) in comparison with tissue transglutaminase antibodies (0.83) and gliadin antibodies (0.82 for IgG, 0.62 for IgA).

CONCLUSIONS

Basic criteria of standardization and quality assessment must be fulfilled by any given test protocol proposed for serologic investigation of celiac disease. The working group has produced robust test protocols and reference materials available for standardization to further improve reliability of serologic testing for celiac disease.

The natural history of gluten sensitivity: report of two new celiac disease patients resulting from a long-term follow-up of nonatrophic, first-degree relatives

OBJECTIVE

Early studies revealed that up to 50% of non-atrophic, first-degree relatives of celiac disease patients exhibit features of gluten sensitivity. However, whether these features progress to a fully expressed celiac disease remain partially known. Our aim was to report two new patients resulting from a prospective, long-term surveillance of relatives who were nonatrophic at initial assessment.

METHODS

After a median time of 86 months (range: 42-102 months) from the baseline assessment, we re-evaluated 44 first-degree relatives of propositi who had taken part in family studies and in whom baseline small intestinal biopsies were normal. At the baseline screening, 21 relatives had positive serum antigliadin antibodies and/or increased intraepithelial lymphocyte infiltration, and 23 did not. In addition, 11 of 18 had a celiac-like response to rectal gluten challenge and 16 of 34 possessed the characteristic HLA DQ2 haplotype (DQA1 0501 DQB1 0201). Re-evaluation was based on celiac-related serology antigliadin (AGA) and endomysial (EmA) antibodies. EmA-positive subjects underwent intestinal biopsy.

RESULTS

At the end of the study, EmA was positive in only two subjects. Histological examination revealed flat small bowel mucosa in both. At baseline, both cases were EmA-negative and no minor histological changes were observed. One was a woman with positive baseline IgA and IgG AGA and a rectal gluten challenge with a celiac-like response; the other patient has presented only with a positive IgG AGA. In both cases, progression was detected in a clinically silent context. Both new patients had the characteristic HLA DQ2 haplotype.

CONCLUSIONS

Our data suggest the need to re-evaluate relatives who have been negative on initial screening for celiac disease. Up to now, the progression to severe enteropathy was only observed in relatives who had presented some evidence of gluten sensitivity and the characteristic HLA DQ2 haplotype. Longer longitudinal studies are necessary to obtain definitive conclusions.

Sugar tests detect celiac disease among first-degree relatives

OBJECTIVES

First-degree relatives of patients with celiac disease are at high risk for developing the disease themselves. Detection of serum antibodies and intestinal permeability tests have been useful to identify candidates for intestinal biopsies. Recently it was demonstrated that abnormal sucrose permeability is a very sensitive marker of active disease. Our objectives in this prospective study were (1) to assess the screening value of permeability tests, and (2) to compare the usefulness of these markers with that of the celiac disease-related serology in screening for celiac disease in a cohort of first-degree relatives of well-known patients.

METHODS

We performed sugar tests in 66 first-degree relatives of probands. Subjects ingested 450 ml of a solution containing sucrose (100 g), lactulose (5 g), and mannitol (2 g). Subsequently, a complete overnight urine collection was obtained. Measurement of sugars was performed by high-performance liquid chromatography. All relatives were evaluated for antigliadin (type IgA and IgG) and endomysial antibodies and subjects positive for any test underwent intestinal biopsy.

RESULTS

Twelve relatives were diagnosed as having small intestinal mucosal atrophy. Increased sucrose permeability was detected in 9 (75%) of these patients. Four false-positive determinations were found but all had gastric erosions, which is known to increase sucrose permeability independently of duodenal damage. Increased lactulose/mannitol ratios were observed in all new celiac patients. An additional nine relatives had positive results; however, four of them did not accept intestinal biopsy and the remaining five did not seem to have histological evidence of disease. Endomysial antibodies were detected in 11 of 12 patients and no false-positive cases were observed. Antigliadin antibodies were 75% sensitive and 88% specific.

CONCLUSIONS

Our study demonstrated that screening using the endomysial antibody test is highly sensitive and specific for detecting celiac disease; however, almost 10% can be missed. The addition of lactulose/mannitol permeability testing to the screening protocol allowed us to detect all relatives who actually presented with evidence of gluten sensitivity. Sucrose permeability exhibited a lower sensitivity; however, it did detect other endoscopically visible lesions.

Characterization of gastric mucosal lesions in patients with celiac disease: a prospective controlled study

OBJECTIVE

Several studies have demonstrated that chronic exposure to gluten may damage the structure and function of the gastric mucosa in gluten-sensitive patients. However, until now, these abnormalities have been incompletely studied. Our purpose in the present study was to characterize, in a prospective controlled study, the endoscopic and histological appearance of the gastric mucosa in a large cohort of patients with celiac disease with and without Helicobacter pylori (H. pylori) infection.

METHODS

We evaluated biopsy specimens taken from the gastric body and antrum of 218 individuals who underwent upper endoscopy for small bowel biopsy. One hundred-four patients had celiac disease (80 of them at the time of diagnosis-untreated). In 114 subjects celiac disease was excluded.

RESULTS

Endoscopic findings did not show a difference between the groups. The prevalence of cases with normal gastric mucosa, chronic superficial gastritis, and atrophic gastritis was similar in patients and controls. Similarly, presence of metaplasia, inflammatory activity, and lymphoid follicles and aggregates did not show differences between the groups. Histological or serological evidence of H. pylori infection was detected in 86% of patients (82% of untreated celiacs and 95% of those on those taking treatment). The infection was highly prevalent in patients (89%) and controls (97%) diagnosed with chronic gastritis. Untreated patients had a significant greater IEL count in the antrum and corpus than controls (p < 0.0001 and p < 0.001, respectively). A global analysis of the data on intraepithelial lymphocyte (IEL) counts in the different populations suggest that the inflammatory state may represent the cumulative effect of H. pylori infection and gluten sensitivity. Only three patients had IEL infiltration compatible with diagnosis of lymphocytic gastritis (count >25%) and three other patients had borderline counts.

CONCLUSIONS

According to our results, celiac disease patients presented a similar prevalence of gastric mucosal abnormalities compared with the control population. Evidence of H. pylori infection was very high compared with the prevalence in the general Argentine population. As a particular observation in our celiac population, the disease was rarely associated with lymphocytic gastritis. We suggest that the chronic inflammatory state evidenced by a gastric mucosal lymphocyte infiltration may be secondary to the combination of H. pylori infection and chronic gluten ingestion in gluten-sensitive subjects.

Usefulness of videoduodenoscopy and vital dye staining as indicators of mucosal atrophy of celiac disease: assessment of interobserver agreement

BACKGROUND

The present study was designed to determine the diagnostic usefulness of videoduodenoscopic inspection alone and the addition of vital dye staining in the detection of celiac disease. We additionally sought to evaluate interobserver agreement for specific duodenoscopic markers of mucosal atrophy.

METHODS

One hundred sixty-seven consecutive subjects who underwent duodenoscopy for intestinal biopsy were included in a prospective controlled study. Endoscopic examination was performed by experienced endoscopists according to a set protocol using methylene blue (1%) dye. All procedures were recorded on videotape, but only 20 (10 with atrophy and 10 normal) were used in a blinded, independent, randomized analysis by five reviewers to evaluate interobserver agreement. Endoscopic signs indicative of mucosal atrophy were as follows: reduction in the number or loss of Kerkring's folds, "scalloped" folds, "mosaic pattern," and visualization of the underlying blood vessels.

RESULTS

Eighty-seven patients had celiac disease (57 newly diagnosed, 30 when treated). Seven treated patients had nonatrophic mucosa. In 80 patients the final diagnosis excluded celiac disease. Videoendoscopic inspection alone correctly identified 75 of 80 patients with complete mucosal atrophy and 86 of 87 with normal mucosa. False-negative diagnoses occurred in treated celiac patients with mild atrophy. Mosaic pattern (89%) and scalloped folds (86%) were the most useful endoscopic signs. Vital dye staining, as assessed by experienced endoscopists, provided identical results to those obtained by inspection alone. Sensitivity, specificity, and positive and negative predictive values for the presence of one or more than one feature were 94%, 100%, 100%, and 96%, respectively. The agreement (kappa statistics) among observers was excellent for the mosaic pattern (kappa: 0.76 for both the videoendoscopic inspection alone and dye staining) and the scalloped folds (kappa: 0.83 and 0.76, respectively) and was fair (kappa: 0.41 and 0.59, respectively) for the reduction in the number or loss of duodenal folds.

CONCLUSION

This study confirms that videoduodenoscopy is useful in the detection of intestinal atrophy. Dye staining produces a better delineation of scalloped folds and mosaic pattern in the atrophic mucosa, but did not provide additional information to the expert endoscopist. Finally, interobserver agreement was excellent for the most prevalent signs.

Gluten sensitivity in patients with primary biliary cirrhosis

OBJECTIVE

Whereas celiac disease and primary biliary cirrhosis have been reported to coexist in the same patient, the frequency of this relationship has not been clarified. Nowadays, the concept of celiac disease has been extended from that of a severe enteropathy to a broader concept of gluten-driven intestinal immunological response. In this study we assessed features of gluten sensitivity in a cohort of patients with primary biliary cirrhosis.

METHODS

Ten patients with primary biliary cirrhosis were evaluated a mean of 2 yr after diagnosis. The following features of gluten sensitivity were assessed: serum antigliadin and endomysial antibodies, small bowel histology (degree of atrophy and quantitative histological parameters), the presence of the typical celiac HLA genotype (DQ2), and intraepithelial lymphocyte response in the rectal mucosa after local gluten instillation (rectal gluten challenge).

RESULTS

Overall, three patients presented evidence of gluten sensitivity. All three had abnormal titers of antigliadin antibody type IgA and one was positive for endomysial antibody. Two patients had partial villous atrophy. The rectal gluten challenge showed a celiac-like response, evidenced by an increase in intraepithelial lymphocyte infiltration after gluten exposure, in the three patients. The characteristic celiac HLA genotypes (DQA1 0501 and DQB1 0201) were identified in three patients. One of them also exhibited other features of gluten sensitivity. However, despite evidence of gluten intolerance, patients had minimal or no symptoms characteristic of celiac disease.

CONCLUSION

We detected features of gluten sensitivity in a high proportion of patients with primary biliary cirrhosis. Further studies should be performed to elucidate the clinical significance of this association.

Lysinuric protein intolerance masquerading as celiac disease: a case report

A 5 1/2-year-old boy presented with delayed growth, chronic diarrhea, and hypoproteinemia. Clinical presentation, initial laboratory data, and evaluation of an intestinal biopsy specimen suggested a diagnosis of celiac disease. Symptoms did not resolve on a gluten-free diet. The development of hyperammonemia prompted further studies that led to the diagnosis of lysinuric protein intolerance. Lysinuric protein intolerance, although a rare disorder, should be included in the differential diagnosis of conditions associated with intestinal villous atrophy.

Long-term effect of gluten restriction on bone mineral density of patients with coeliac disease

AIM

To assess the long-term effect of a gluten-free diet on bone mineral density of adults with untreated coeliac disease.

METHODS

Bone mineral density was assessed at baseline and after a mean duration of 37 months of treatment in 25 unselected newly diagnosed coeliac patients.

RESULTS

At baseline, osteopenia (> -1 s.d. below normal) was evident in the lumbar spine and total skeleton in 18 (72%) and 21 (84%) patients, respectively. At the end of the study, bone density had increased (mean bone mass Z-score increase: Z-score +1.0 for the lumbar spine and +1.1 for total skeleton) in 22 and 23 patients, respectively. Patients who adhered to strict gluten restriction (n = 15) demonstrated a similar bone remineralization in the spine than those patients with partial compliance (n = 10) (mean Z-score increase: +1.0, in both areas). A greater mean annual change in Z-score in the total skeleton was noted in patients who followed strict gluten restriction (0.4 +/- 0.1) respect to those with partial compliance (0.3 +/- 0.1); however, this difference was not statistically significant. Pre-menopausal women had significantly greater remineralization that post-menopausals (P > 0.05). Remineralization showed an inverse correlation with the degree of basal osteopenia (r = -0.525; P < 0.002).

CONCLUSIONS

Long-term treatment with gluten-free diet produces a significant improvement in bone density in coeliac patients. Remineralization was more pronounced in patients who better comply with gluten-free diet, in pre-menopausal women and in patients with the lowest baseline bone mineral density.