Increased prevalence of celiac disease in girls with Turner syndrome detected using antibodies to endomysium and tissue transglutaminase

Turner Syndrome Mosaicism after Diagnosis of Coeliac Disease-A High Index of Clinical Suspicion Required?

The association of coeliac disease (CD) in girls with Turner syndrome (TS) is well described. There is, however, a paucity of current research describing TS in patients with known CD. We report two cases of mosaic Turner syndrome diagnosed in girls with CD who failed to achieve expected catch-up growth despite strict adherence to a gluten-free diet (GFD) and the normalisation of TGA-IgA levels. We highlight the need to consider additional diagnoses in patients with CD and ongoing faltering growth. In such patients, referral to a paediatric endocrinologist and relevant investigations, including genetic investigations, should be considered if growth remains suboptimal after one year with a GFD. First-line investigations should include thyroid function, IGF-1, cortisol, gonadotrophins, oestrogen/testosterone, prolactin, karyotype and a bone age X-ray. Clinical suspicion in this situation is key, as an early diagnosis of TS will allow timely treatment with growth hormone, inform discussion around ovarian function and allow screening for important TS associations.

Celiac disease in children: A review of the literature

Celiac disease is an immune-mediated systemic disease triggered by intake of gluten in genetically susceptible individuals. The prevalence of celiac disease in the general population is estimated to be 1% in the world. Its prevalence differs depending on geographical and ethnic variations. The prevalence of celiac disease has increased significantly in the last 30 years due to the increased knowledge and awareness of physicians and the widespread use of highly sensitive and specific diagnostic tests for celiac disease. Despite increased awareness and knowledge about celiac disease, up to 95% of celiac patients still remain undiagnosed. The presentations of celiac disease have significantly changed in the last few decades. Classical symptoms of celiac disease occur in a minority of celiac patients, while older children have either minimal or atypical symptoms. Serologic tests for celiac disease should be done in patients with unexplained chronic or intermittent diarrhea, failure to thrive, weight loss, delayed puberty, short stature, amenorrhea, iron deficiency anemia, nausea, vomiting, chronic abdominal pain, abdominal distension, chronic constipation, recurrent aphthous stomatitis, and abnormal liver enzyme elevation, and in children who belong to specific groups at risk. Early diagnosis of celiac disease is very important to prevent long-term complications. Currently, the only effective treatment is a lifelong gluten-free diet. In this review, we will discuss the epidemiology, clinical findings, diagnostic tests, and treatment of celiac disease in the light of the latest literature.

Prevalence of Celiac Disease in Patients With Turner Syndrome: Systematic Review and Meta-Analysis

Introduction: Celiac disease (CD) is a multifactorial autoimmune disorder, and studies have reported that patients with Turner syndrome (TS) are at risk for CD. This systematic review and meta-analysis aimed to quantify the weighted prevalence of CD among patients with TS and determine the weighted strength of association between TS and CD.

Methods: Studies published between January 1991 and December 2019 were retrieved from four electronic databases: PubMed, Scopus, Web of Science, and Embase. Eligible studies were identified and relevant data were extracted by two independent reviewers following specific eligibility criteria and a data extraction plan. Using the random-effects model, the pooled, overall and subgroup CD prevalence rates were determined, and sources of heterogeneity were investigated using meta-regression.

Results: Among a total of 1,116 screened citations, 36 eligible studies were included in the quantitative synthesis. Nearly two-thirds of the studies (61.1%) were from European countries. Of the 6,291 patients with TS who were tested for CD, 241 were diagnosed with CD, with a crude CD prevalence of 3.8%. The highest and lowest CD prevalence rates of 20.0 and 0.0% were reported in Sweden and Germany, respectively. The estimated overall weighted CD prevalence was 4.5% (95% confidence interval [CI], 3.3–5.9, I², 67.4%). The weighted serology-based CD prevalence in patients with TS (3.4%, 95% CI, 1.0–6.6) was similar to the weighted biopsy-based CD prevalence (4.8%; 95% CI, 3.4–6.5). The strength of association between TS and CD was estimated in only four studies (odds ratio 18.1, 95% CI, 1.82–180; odds ratio 4.34, 95% CI, 1.48–12.75; rate ratio 14, 95% CI, 1.48–12.75; rate ratio 42.5, 95% CI, 12.4–144.8). Given the lack of uniformity in the type of reported measures of association and study design, producing a weighted effect measure to evaluate the strength of association between TS and CD was unfeasible.

Conclusion: Nearly 1 in every 22 patients with TS had CD. Regular screening for CD in patients with TS might facilitate early diagnosis and therapeutic management to prevent adverse effects of CD such as being underweight and osteoporosis.

Coeliac disease in childhood: An overview

Coeliac disease (CD) is an autoimmune condition, characterised by an immunological response to ingestion of gluten in genetically susceptible individuals, affecting about 1% of the population in many regions of the world. Increased knowledge regarding the pathogenesis, improved diagnostic techniques and increased awareness over the years have transformed our understanding of CD such that it is no longer a rare enteropathy, but rather a common multisystem disorder which affects individuals of all ages and results in wide-ranging clinical manifestations. Only a minority of children now present with the classical clinical picture of profound diarrhoea and malnutrition. An increasing number of children with CD present with either mild, non-specific gastrointestinal symptoms or extra-intestinal manifestations or even be asymptomatic, as in many screening-detected children. Knowledge about these diverse manifestations and a high index of suspicion is essential so that appropriate investigations can be undertaken, diagnosis established and treatment initiated. Although traditionally small bowel biopsy is considered essential for the diagnosis, recent guidelines from various professional bodies have paved the way to a biopsy-free diagnosis in a subset of symptomatic children. Life long, strict gluten-free diet still remains the only effective treatment at present, although several novel therapeutic agents are in various phases of clinical trials.

Turner Syndrome and Celiac Disease: A Case-Control Study

OBJECTIVE

Turner syndrome (TS) is the most common sex chromosome abnormality in females. Previous research has indicated a high prevalence of celiac disease (CD) in TS, but data have mostly been limited to case series at tertiary centers. We aimed to examine the risk for CD in individuals with TS compared with the general population.

METHODS

This Swedish nationwide case-control study included individuals with CD and controls born in 1973-2006. The study consisted of 2 groups: (1) 7548 females with biopsy-verified CD (villous atrophy; Marsh stage 3) diagnosed until January 2008 according to histopathology report data from all 28 Swedish pathology departments and (2) 34 492 population-based controls matched by gender, age, calendar year of birth, and county of residence. TS, diagnosed by the end of 2009, was identified using prospectively recorded data from 3 nationwide health registries. Odds ratios (ORs) for CD were calculated using conditional logistic regression.

RESULTS

Of the 7548 females with CD, 20 had a diagnosis of TS (0.26%) compared with 21 of 34 492 controls (0.06%), corresponding to an OR of 3.29 (95% confidence interval [CI] 1.94-5.56) for CD in individuals with TS. The risk of CD in females with TS ranged from twofold (OR 2.16; 95% CI 0.91-5.11) in the first 5 years of life to a more than fivefold increase in females aged >10 years at CD diagnosis (OR 5.50; 95% CI 1.53-19.78). The association between TS and CD was largely unaffected by concurrent type 1 diabetes.

CONCLUSIONS

Females with TS are more likely to develop CD. This study supports active case-finding for CD in TS.

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.

Screening for celiac disease among patients with Turner syndrome in Brasília, DF, midwest region of Brazil

CONTEXT

Several studies have demonstrated a higher prevalence of celiac disease (CD) among females with Turner syndrome when compared to the general population. Nevertheless, there is no record in literature concerning this investigation among Brazilian patients.

OBJECTIVE

To assess the prevalence of CD among a group of Brazilian patients with Turner syndrome.

METHODS

Fifty-six females with Turner syndrome and on gluten-containing diet were screened for CD utilizing immunoglobulin A antiendomysium (IgA-EMA) and immunoglobulin A anti-tissue transglutaminase (IgA-tTG) antibody assays. Additionally, they were genotyped for CD human leukocyte antigen (CD-HLA) predisposing alleles. Patients showing positivity in serological testing were offered to perform small intestine biopsy for histological confirmation.

RESULTS

Mean age at diagnosis of Turner syndrome was 5.5 ± 4.4 years; mean age at screening for CD was 17.0 ± 9.3 years (from 10 months of age to 52 years). Two girls were positive for IgA-EMA and IgA-tTG, presented predisposing HLA-DQ2 alleles and both had the diagnosis of CD confirmed by jejunal biopsy.

CONCLUSION

The 3.6% prevalence of biopsy-proven CD among this group of females with Turner syndrome is 10 times higher than the one among females from the general population of the same geographical area. This result provides additional support to an association between these two disorders and restates that girls and women with Turner syndrome represent a high risk population for developing CD.

Autoimmune and gastrointestinal dysfunctions: does a subset of children with autism reveal a broader connection?

A large number of autoimmune disorders have a gastrointestinal (GI) dysfunction component that may interplay with genetic, hormonal, environmental and/or stress factors. This narrarive review investigates possible links between autism, immune system abnormalities and GI symptoms in a subgroup of children with autism. A literature search on Medline (1950 to September 2010) was conducted to identify relevant articles by using the keywords 'autism and gastrointestinal' (71 publications) and 'autism and immune' (237 publications), cross-referencing and general searching to evaluate the available literature on the immunological and GI aspects of autism. Sufficient evidence exists to support that a subgroup of children with autism may suffer from concomitant immune-related GI symptoms.

Adult celiac disease with acetylcholine receptor antibody positive myasthenia gravis

Celiac disease has been associated with some autoimmune disorders. A 40-year-old competitive strongman with celiac disease responded to a gluten-free diet, but developed profound and generalized motor weakness with acetylcholine receptor antibody positive myasthenia gravis, a disorder reported to occur in about 1 in 5000. This possible relationship between myasthenia gravis and celiac disease was further explored in serological studies. Frozen stored serum samples from 23 acetylcholine receptor antibody positive myasthenia gravis patients with no intestinal symptoms were used to screen for celiac disease. Both endomysial and tissue transglutaminase antibodies were examined. One of 23 (or, about 4.3%) was positive for both IgA-endomysial and IgA tissue transglutaminase antibodies. Endoscopic studies subsequently showed duodenal mucosal scalloping and biopsies confirmed the histopathological changes of celiac disease. Celiac disease and myasthenia gravis may occur together more often than is currently appreciated. The presence of motor weakness in celiac disease may be a clue to occult myasthenia gravis, even in the absence of intestinal symptoms.

Genetic background of celiac disease and its clinical implications

Celiac disease (CD) is a complex genetic disorder with multiple contributing genes. Linkage studies have identified several genomic regions that probably contain CD susceptibility genes. The most important genetic factors identified are HLA-DQ2 and HLA-DQ8, which are necessary but not sufficient to predispose to CD. The associations found in non-HLA genomewide linkage and association studies are much weaker. This might be because a large number of non-HLA genes contributes to the pathogenesis of CD. Hence, the contribution of a single predisposing non-HLA gene might be quite modest. Practically all CD patients carry HLA-DQ2 or HLA-DQ8, while the absence of these molecules has a negative predictive value for CD close to 100%. Genetic risk profiles for CD would be helpful in clinical practice for predicting disease susceptibility and progression.

Pregnancy in a woman with Turner syndrome and celiac disease

BACKGROUND

Studies on fertility in women with Turner syndrome have shown that spontaneous pregnancies occur in about 2-7% of patients. Fertility problems and obstetrical complications are frequently observed in untreated patients with celiac disease. We report the case of a patient, affected by Turner syndrome and celiac disease, in whom a spontaneous pregnancy occurred.

CASE

One patient affected by Turner syndrome at the age of 30 yr conceived spontaneously. Celiac disease was diagnosed during pregnancy. The pregnancy progressed uneventfully. After 39 weeks of gestation, she vaginally delivered a normal male infant.

CONCLUSION

Our patient had a successful pregnancy, giving birth to a healthy child, although she presented two pathological conditions affecting fertility and pregnancy outcome: Turner syndrome and celiac disease.

Complications of coeliac disease: are all patients at risk?

Coeliac disease is a common condition that is increasingly being recognised as a result of the development of sensitive and specific serology. The diagnosis of coeliac disease and its subsequent treatment with a gluten-free diet have implications for the patient, not just for symptom control but also for the possible effect on quality of life and risk of complications. Whether the mode of presentation of coeliac disease has an effect on survival or risk of complication is yet unclear. This article reviews the available evidence regarding these issues.

Coeliac disease: a diverse clinical syndrome caused by intolerance of wheat, barley and rye

Coeliac disease is a lifelong intolerance to the gluten found in wheat, barley and rye, and some patients are also sensitive to oats. The disease is genetically determined, with 10% of the first-degree relatives affected and 75% of monozygotic twins being concordant. Of the patients with coeliac disease 95% are human leucocyte antigen (HLA)-DQ2 or HLA-DQ8 positive. Characteristically, the jejunal mucosa becomes damaged by a T-cell-mediated autoimmune response that is thought to be initiated by a 33-mer peptide fragment in A2 gliadin, and patients with this disorder have raised levels of anti-endomysium and tissue transglutaminase antibodies in their blood. Coeliac disease is the major diagnosable food intolerance and, with the advent of a simple blood test for case finding, prevalence rates are thought to be approximately 1:100. Classically, the condition presented with malabsorption and failure to thrive in infancy, but this picture has now been overtaken by the much more common presentation in adults, usually with non-specific symptoms such as tiredness and anaemia, disturbance in bowel habit or following low-impact bone fractures. Small intestinal biopsy is necessary for diagnosis and shows a characteristically flat appearance with crypt hypoplasia and infiltration of the epithelium with lymphocytes. Diet is the key to management and a gluten-free diet effectively cures the condition. However, this commitment is lifelong and many aisles in the supermarket are effectively closed to individuals with coeliac disease. Compliance can be monitored by measuring antibodies in blood, which revert to negative after 6-9 months. Patients with minor symptoms, who are found incidentally to have coeliac disease, often ask whether it is necessary to adhere to the diet. Current advice is that dietary adherence is necessary to avoid the long-term complications, which are, principally, osteoporosis and small bowel lymphoma. However, risk of these complications diminishes very considerably in patients who are on a gluten-free diet.

Can tissue transglutaminase antibody titers replace small-bowel biopsy to diagnose celiac disease in select pediatric populations?

OBJECTIVES

The use of screening tests for celiac disease has increased the number of patients referred for evaluation. We proposed that the subgroup of patients with very high tissue transglutaminase antibody (TTG) titers is positive for celiac disease and a small-bowel biopsy is not necessary to make the diagnosis. A gluten-free diet should be attempted and, if the patient's symptoms do not improve, then a biopsy should be performed to confirm the diagnosis.

METHODS

A chart review of data for 103 patients who underwent both TTG testing and a small-bowel biopsy was performed. We examined the impact of using TTG values of >100 U and <20 U as cutoff values and suggested performing biopsies for patients with TTG values of 20 to 100 U, as is current practice.

RESULTS

Fifty-eight of 103 patients demonstrated positive biopsy results. Forty-nine of 103 patients had TTG levels of >100 U, with 48 of 49 exhibiting positive biopsy results. Only 7 of 16 patients with TTG values of 20 to 100 U exhibited positive biopsy results. Three patients with TTG levels of <20 U had positive biopsies; 2 were IgA negative and 1 had a duodenal ulcer. With the cutoff values of >100 U and <20 U with known IgA status, the sensitivity was 0.980 (48 of 49 cases) and the specificity was 0.972 (35 of 36 cases). An incremental cost analysis found that this proposal could potentially decrease the costs of investigation and diagnosis by almost 30%.

CONCLUSIONS

When the cutoff values were changed to >100 and <20 U and IgA levels were verified, the sensitivity and specificity were very high. Patients with mid-range TTG values (20-100 U) or values of <20 U with negative IgA status should continue to undergo biopsies for diagnosis of celiac disease.

Should all children be screened for celiac disease?

To address the issue of screening children for celiac disease, current evidence has been summarized and placed within the context of 8 established criteria for childhood screening. Screening all children for celiac disease is not recommended at this time. Areas with gaps in knowledge are identified as areas in need of further study. These include the timing of screening, defining the natural history of screening-identified celiac disease, developing tools to predict disease onset and disease remission, and the risks of screening.

Practical considerations for the identification and follow-up of children with celiac disease

Celiac disease is an immune-mediated enteropathy affecting 0.5% to 1% of children and is induced by dietary gluten in susceptible individuals carrying the human leukocyte antigen DQ2 or DQ8 heterodimer. If serological screening is positive or if a patient displays suggestive symptoms, an endoscopic biopsy of the distal duodenum is required to confirm the diagnosis. Symptoms of celiac disease are often mild or absent. Overt malabsorption occurs in only 2% to 10% of children. Individuals with a higher risk of developing celiac disease, including first-degree relatives of affected patients and children with type I diabetes, Turner syndrome, Williams syndrome or Down syndrome, should be offered screening for celiac disease along with a discussion of the implications. If serological testing is negative, a high index of suspicion should remain if malabsorption, iron deficiency or osteopenia is present. Also, immunoglobulin A deficiency should be excluded. At-risk individuals should undergo serial serological screening. Lifelong adherence to a gluten-free diet is the only treatment. If left untreated, symptomatic children with celiac disease carry an increased risk of developing osteoporosis and have a greater lifetime risk of cancer. The long-term outcome of undiagnosed or untreated asymptomatic individuals is less clear.

Tissue transglutaminase antibodies in patients with end-stage heart failure

OBJECTIVE

For celiac disease (CD), screening a trend has recently emerged to measure tissue transglutaminase antibodies (tTGA) by immunoassays instead of the more laborious endomysial antibodies (EmA), as they recognize the same target, tissue transglutaminase (tTG). However, a high rate of false-positive results has been reported in some patient series with diseases known to be associated with CD. Moreover, tTG is a ubiquitous, multifunctional enzyme, overexpressed in experimental models of heart failure. Therefore, we assessed the specificity of tTGA assays in a large series of EmA-negative patients with end-stage heart failure.

METHODS

We studied 288 patients with end-stage heart failure and 60 blood donors. No subject had clinical evidence of CD or IgA deficiency, and all were EmA negative. Serum IgA and IgG tTGA were measured by means of commercial kits using as substrate, either guinea pig or recombinant human tTG. Blocking studies and Western blots were also performed using recombinant human tTG.

RESULTS

All blood donor sera were IgA tTGA negative. IgA tTGA positivity was observed in 47.6% and 49.1% of patients with heart failure using, respectively, guinea pig tTG and recombinant human tTG as substrates. Preincubation of positive sera with recombinant human tTG resulted in 81% blocking of IgA tTGA in immunoassay. Western blot analysis confirmed the presence of antibodies against recombinant human tTG. IgA tTGA-positive sera were also IgG tTGA positive.

CONCLUSIONS

IgA and IgG tTGA occur in a large number of EmA-negative patients with end-stage heart failure, and their presence is unlikely to be caused by concomitant CD.

Turner syndrome in childhood and adolescence

Turner syndrome (TS) is the most common chromosomal disorder causing short stature in females. The short stature is caused at least in part by haploinsufficiency of the short stature homeobox (SHOX) gene. Complete spontaneous puberty may occur in approximately 16% of patients, with spontaneous pregnancy in up to 4%. The final height of untreated TS girls is 86-88% of the mean adult female height. Growth hormone (GH) given alone or with oxandrolone improves final height. The major factors determining the outcome of GH therapy are the dose of GH used and the number of years of GH therapy prior to oestrogenization. Pubertal induction in TS should be individualized bearing in mind growth optimization and psychological issues. Adolescents and adults with TS may face a range of medical, fertility and psychosocial issues. Psychological support for TS individuals and families is important throughout life and should ideally be provided by both health professionals and TS support groups.