P. Mariani

The gluten-free diet: a nutritional risk factor for adolescents with celiac disease?

BACKGROUND The gluten-free diet is the standard therapy for patients affected by celiac disease, although compliance with the diet is not optimal in adolescents or adults. Moreover, the gluten-free diet may induce nutritional imbalances. METHODS Alimentary habits and diet composition were examined in 47 adolescents with celiac disease and 47 healthy aged-matched control subjects. All subjects compiled a 3-day alimentary record that allowed determination of their energy intakes: the macronutrient composition of their diets; and their iron, calcium, and fiber intakes. To evaluate compliance with the gluten-free diet, immunoglobulin A antigliadin and antiendomysium antibodies were assessed in all with celiac disease. RESULTS The analysis of the records and the results of antibody levels showed that 25 subjects strictly followed dietetic prescriptions (group 1A), whereas 22 patients consumed gluten-containing food (group 1B). Those with celiac disease and control subjects (group 2) consumed a normocaloric diet. Lipid and protein consumption was high, however, and the consumption of carbohydrates low. Moreover, dietary levels of calcium, fiber, and especially in girls, iron, were low. These nutritional imbalances were significantly more evident in group 1A than in group 1B, as a consequence of poor alimentary choices. Moreover, in group 1A overweight and obesity were more frequent (72%) than in group 1B (51%) and in the control subjects (47%). CONCLUSIONS In people with celiac disease, adherence to a strict gluten-free diet worsens the already nutritionally unbalanced diet of adolescents, increasing elevated protein and lipid consumption. In the follow-up of patients with celiac disease, considerable effort has yet to be made to improve compliance with a gluten-free diet, and especially to control the nutritional balance of the diet in compliant patients.

Patchy villous atrophy of the duodenum in childhood celiac disease.

Objectives Patchy villous atrophy of the duodenal mucosa has been described in adults with untreated celiac disease (CD) but not in children. The authors evaluated the presence and the distribution of villous atrophy in children with celiac disease to see whether this histologic pattern exists in children. Methods We studied 95 children at diagnosis (Group 1) and seven during gluten challenge (Group 2). We measured anti-endomysium antibodies (EMA) by immunofluorescence on monkey esophagus, antihuman-tissue transglutaminase autoantibodies (anti-tTG Abs) by radioimmunoprecipitation, and HLA-DQ2/DQ8 heterodimers by polymerase chain reaction using specific primers. During upper intestinal endoscopy, at least five duodenal biopsy samples were obtained, one from the duodenal bulb and four from the distal duodenum. Results Thirteen of 95 (13.7%) patients in Group 1 and in 3 of 7 (42.9%) in Group 2 had patchy villous atrophy of the duodenum. In all 16 patients, villous atrophy of the bulb was present. In four children from Group 1, villous atrophy was observed only in the bulb samples. EMA, anti-tTG Abs, and HLA-DQ2/DQ8 heterodimers were present in all patients. Fourteen of 16 had symptomatic CD, and two were silent, detected during screening in subjects at risk for CD. Conclusions This is the first study demonstrating that children with CD may have patchy villous atrophy of the duodenum. The bulb mucosa may be the only duodenal area involved, both at diagnosis and after gluten challenge. Therefore, multiple endoscopic biopsies should always be performed, not only in the distal duodenum, but also in the bulb.

Genetic contribution of the HLA region to the familial clustering of coeliac disease

In order to assess the effect of the HLA region on familiality of coeliac disease (CD), we carried out a study on 121 CD index cases and 325 first degree relatives. The transmission disequilibrium test confirmed the importance of the HLA‐DR3 haplotype in CD susceptibility. However, the different distortion found in affected children inheriting maternal or paternal DR3 alleles suggested that the sex of the parent might influence the risk conferred by this haplotype. The increase in risk to siblings of affected individuals relative to the risk in the general population (λs) and the contribution of the HLA genes to this clustering (λsHLA) have also been estimated. Non‐overlapping data from the literature have been collected and combined with our sample to extend such analysis. Then, the percentage contribution of the HLA region to the development of CD among siblings was 36·2%. This result confirms that the HLA genotypes are an important genetic background to CD development but shows that additional susceptibility factors remain to be identified.

Prevalence and clinical picture of celiac disease in italian down syndrome patients: a multicenter study.

Background A multicenter research study of Down syndrome patients was carried out to estimate the prevalence of celiac disease in patients with Down syndrome and to show clinical characteristics and laboratory data of Down syndrome patients. Methods The authors studied 1,202 Down syndrome patients. Fifty-five celiac disease patients (group 1) were compared with 55 immunoglobulin A antigliadin–positive antiendomysium antibodies–negative patients (group 2) and with 57 immunoglobulin A antigliadin–negative antiendomysium antibodies–negative patients (group 3). Results Celiac disease was diagnosed in 55 of 1,202 Down syndrome patients (4.6%). In group 1, weight and height percentiles were shifted to the left, whereas these parameters were normally distributed in groups 2 and 3. In celiac patients, diarrhea, vomiting, failure to thrive, anorexia, constipation, and abdominal distension were higher than in the other two groups. Low levels of hemoglobinemia, serum iron, and calcium were observed more frequently in group 1. The diagnosis of celiac disease was made after a mean period of 3.8 years from the initiation of symptoms. Sixty-nine percent of patients showed a classic presentation, 11% had atypical symptoms, and 20% had silent celiac disease. Autoimmune disorders were more frequent (30.9%) in group 1 than in the other two groups examined (15%;P < 0.05). Conclusions This study reconfirms a high prevalence of celiac disease in Down syndrome. However, the diagnostic delay, the detection of atypical symptoms or silent form in one third of the cases, and the increased incidence of autoimmune disorders suggest the need for the screening of celiac disease in all Down syndrome patients.

Importance of gluten in the induction of endocrine autoantibodies and organ dysfunction in adolescent celiac patients

OBJECTIVE:It is well known that a high number of celiac patients may develop autoantibodies against endocrine glands, but it has not yet been clarified if this increased autoimmune response and the impaired organ function that can develop may be related to the presence or absence of gluten in the diet. The aim of the present study was to evaluate the effect of gluten on the autoimmunity and function of the endocrine glands in adolescent celiac patients.METHODS:To clarify this aspect we investigated 44 patients (28 females), aged 11–20 yr (15.21 ± 2.7 yr): 25 (mean age, 15.1 ± 2.2 yr) on a gluten-free diet (treated patients) and 19 (mean age 15.4 ± 2.9 yr) with a diet containing gluten (untreated patients). Forty adolescent subjects, aged 14–19 yr (mean age, 14.9 ± 2.7 yr), of whom 20 were females, were studied as controls. Antibodies against the thyroid, adrenal, and pancreas were evaluated. Thyroid-stimulating hormone FT3, FT4, T3, T4, dehydroepiandrosterone sulphate, 17-OH progesterone, and cortisol, analyzed basally and 60 min after intravenous ACTH stimulation, were assayed to evaluate thyroid and adrenal function. The fasting glycemia level was used to evaluate the endocrine pancreas function. An ultrasonogram of the thyroid gland was performed on all patients. HLA class II typing for DR3 and DQB1 was performed in 32 of 44 patients.RESULTS:Seven of 44 (15.9%) patients were positive for antibodies against peroxidase. Six of 44 (13.6%) were positive for antibodies against thyreoglobulin and four of them also showed positive antibodies against peroxidase. Therefore, in nine of 44 at least one antibody directed against thyroid tissue was positive. Seven of 44 (15.9%) were positive for antibodies against islet cell, one of 44 (2.3%) positive for antibodies against glutamic acid decarboxilase, one of 44 (2.3%) positive for antibodies against insulin, and none for antibodies against islet cell- 512bdc. In 15 of 44 (34%) at least one antibody against an endocrine tissue was positive. The genotype DR3 was found in 21 of 32 (65.6%) celiac patients (10 in the untreated and 11 in the treated group, respectively) and the genotype DQB1*02 (DQ2) was found in 30 of 32 (93.8%) patients (16 in the treated and 14 in the untreated group, respectively). DHA-S values were significantly lower in the untreated (30.5 ± 28.5 μg/dl) than in the treated group (61.3 ± 59.4 μg/dl, p < 0.05), and both showing significantly (p < 0.01) lower levels with respect to the controls (161 ± 52 μg/dl). One patient showed diabetes, another one clinical hypothyroidism (thyroid-stimulating hormone > 6), and two patients showed preclinical hypothyroidism. Interestingly, at least one antibody was positive in 10 of 19 untreated patients (52.6%) but only in five of 25 treated patients (20%), with a significantly different distribution (p < 0.001) between the two groups and without differences in the HLA genotype. The ultrasonographic evaluation of the thyroid resulted in a pathological score in six patients of the 44 examined (13.6%), suggesting the presence of thyropathy.CONCLUSIONS:The main results of this study are the high incidence of thyroid and pancreatic antibodies, and the possible role of gluten in the induction of the antibodies as well as, in few cases, the consequent organ dysfunction.

Duodenal bulb biopsies in celiac disease: a multicenter study

Objectives: Celiac disease (CD)–related lesions have been reported in duodenal bulb biopsies, sometimes the bulb mucosa being the only one affected. The aim was to verify in a significant series whether histological lesions are always present in the bulb of celiac patients, what is the prevalence of lesions when isolated to the bulb, and if similar lesions are present in nonceliac subjects. Methods: We studied 665 children with CD (241 males, range 9 months–15 years, 8 months), at diagnosis on a gluten-containing diet, and 348 age- and sex-matched gastroenterological controls submitted to upper endoscopy for gastroenterological complaints. During endoscopy, multiple biopsies (1 bulb and 4 distal duodenum samples) were taken. Anti-endomysium antibodies were evaluated by immunofluorescence method, anti–human tissue–transglutaminase antibodies by an enzyme-linked immunosorbent assay or radioimmunoassay. Human leukocyte antigen-DRB1, -DQA1, and -DQB1 genes were typed by polymerase chain reaction sequence–specific primers repeat method. Results: In all of the patients with CD, histological lesions were present in the bulb sample; in 16 of them, the lesions were present only in the bulb. Patchy villous atrophy was found in 20 children. All of the patients with CD were anti-endomysium and/or anti-transglutaminase positive. The controls showed neither autoantibody positivity nor mucosal changes compatible with CD. Conclusions: This study demonstrated that CD-related histological lesions are always present in the bulb; sometimes this specific site is the only one affected. Therefore, we suggest taking 2 biopsies from the bulb and 2 from the distal duodenum for CD diagnosis.

Radioimmunoassay to detect antitransglutaminase autoantibodies is the most sensitive and specific screening method for celiac disease

OBJECTIVE:The aim of this study was to establish the most sensitive and specific screening method for celiac disease. We tested three methods based on different principles, which all detect autoantibodies against the same antigen (tissue transglutaminase).METHODS:Sixty-two celiac children at the first biopsy (group 1), 78 celiac children on a gluten-free diet (group 2), 14 celiac children on a gluten-challenge (group 3), and 56 controls with a normal duodenal mucosa (group 4) were studied. The methods used were: 1) radioimmunoprecipitation assay using recombinant tissue transglutaminase (RIA); 2) commercial enzyme immunoassay using guinea pig tissue transglutaminase (ELISA); and 3) indirect immunofluorescence method for detection of antiendomysium antibodies (IF-EMA).RESULTS:RIA antitransglutaminase autoantibodies were detected in 100% of group 1, 43.6% of group 2, 100% of group 3, and none of the control subjects. ELISA antitransglutaminase autoantibodies were detected in 90.3% of group 1, 9% of group 2, 78.6% of group 3, and in none of the control subjects. IF-EMA were detected in 95.2% of group 1, 11.5% of group 2, 92.3% of group 3, and 1.8% of the controls.CONCLUSIONS:Our results demonstrate a very high sensitivity and specificity of the RIA method to detect antitransglutaminase autoantibodies in comparison to ELISA and IF-EMA assays. We can explain this finding with the use of human recombinant antigen and the increased capacity of the RIA method to detect low titers of autoantibodies. If our data are confirmed by studies on larger series, tissue transglutaminase RIA could be proposed as the best screening method for celiac patients.

Short stature as the primary manifestation of monosymptomatic celiac disease

It is generally accepted that celiac disease (CD) must always be taken into consideration when dealing with children manifesting growth failure. It is therefore important to have laboratory tests capable of detecting patients who should undergo intestinal biopsy. Auxological and endocrine parameters, bone age, some nutritional indices (hemoglobin, serum iron, calcium, total protein, and albumin), and anti-gliadin antibodies (AGA) IgA and IgG and 1-h blood xylose levels were evaluated in 49 children of short stature. On the basis of the intestinal biopsy, 29 (59.1%) patients affected by CD were found. When patients with atrophic and normal intestinal mucosa were compared, significant differences in the frequency of pathological values of hemoglobinemia, serum iron, AGA, and 1-h blood xylose levels were found, whereas no difference was observed in the levels of serum calcium, total protein, and albumin. Bone age was delayed in 81% of the celiac patients and in 47% of the controls. In particular, AGAs were found in 27 of 29 celiac patients and in three control subjects who showed a low level of one of the two antibodies. The results of our study demonstrate that AGA (IgA and IgG), together with 1-h blood xylose, hemoglobinemia, serum iron, and family history of CD determination, are extremely useful for screening patients of short stature. This type of screening cannot, however, replace the intestinal biopsy because such tests cannot be completely sensitive and specific.

Serologic and genetic markers of celiac disease: A sequential study in the screening of first degree relatives

Objectives: The prevalence of celiac disease (CD) among the relatives and the complications of an undiagnosed CD prompted us to identify a useful disease screening strategy. Methods: We studied 441 first degree relatives of 208 CD patients by immunoglobulin (Ig)A antiendomysium antibodies (EMA) and radioimmunoprecipitation assay (RIA) IgA antitransglutaminase autoantibodies (TGAA). Of these, 364 were typed for human leukocyte antigen-DRB1, -DQA1, and -DQB1 genes by the polymerase chain reaction sequence specific primers method. It was suggested to the autoantibody-positive subjects that they should undergo intestinal biopsy. Results: TGAA were positive in 46 of 439 relatives, EMA in 38; intestinal lesions related to CD were present in 40 subjects. We also found two immunodeficient fathers with duodenal villous atrophy. In three serology-positive subjects, permission for intestinal biopsy was refused; for another three serology-positive cases, duodenal mucosa was normal. Thus, the strict CD prevalence resulted 9.5%, the enlarged prevalence 10.9%. The DQ2/DQ8 heterodimers were carried in 231 of 364 subjects and in 38 of 40 biopsy-proven celiac patients. Three DQ2-positive parents became positive to the serology during a long-lasting follow-up. Conclusions: On the basis of a carefully conducted study, CD prevalence in our series was seen as very high. These data suggest an accurate algorithm to select candidates for intestinal biopsy among CD high-risk subjects. First, an evaluation of the sensitive RIA TGAA and of total IgA (in IgA deficiency RIA IgG anti-tissue transglutaminase assay) should be performed. Then, an evaluation of the TGAA and the genetic study would be advisable 2 to 3 years later in negative subjects. Those carrying the DQ2/DQ8 heterodimers should continue the serologic follow-up; the others need a clinical follow-up.

A study of italian pediatric celiac disease patients confirms that the primary HLA association is to the DQ(α1*0501, β1*0201) heterodimer

Abstract Celiac disease (CD) has been recently reported to be primarily associated with the DQ(α1∗0501, β1∗0201) heterodimer encoded in cis on DR3 haplotype and in trans in DR5, 7 heterozygous individuals. The high incidence of DR5, 7 heterozygotes, reflecting the high frequency of the DR5 allele in Italy, makes the analysis of the Italian CD patients critical. Polymerase chain reaction-amplified DNA from 50 CD patients and 50 controls, serologically typed for DR and DQw antigens, was hybridized with five DQA1-specific oligonucleotide probes detecting DQA1 ∗0101 + 0102 + 0103, DQA1 ∗0201, DQA1 ∗0301 + 0302, DQA1 ∗0401 + 0501 and DQA1 ∗0501 and a DQB1-sequence-specific oligonucleotide probe recognizing DQB1 ∗0201 allele. As expected by the DR-DQ disequilibria, DQA1 ∗0201 [62% in patients versus 26% in controls, relative risk (RR) = 5] and DQA1 ∗0501 (96% versus 56%, RR = 19) show positive association with the disease. Of CD patients, 92% (50% DR3 and 42% DR5,7) compared to 18% of the controls carry both DQA1 ∗0501 and DQB1 ∗0201 alleles, so that the combination confers an RR of 52, higher than both the risks of the single alleles ( DQA 1 ∗ 0501 RR = 19, DQB 1 ∗ 0201 RR = 30 ), confirming the primary role of the dimer in determining genetic predisposition to CD both in DR3 and in DR5, 7 subjects.