Celiac disease

Editorial: Celiac disease in Turkey: lessons from the fertile crescent

Celiac disease (CD) is as frequent in Turkey as in Western countries. This finding challenges old theories hypothesizing a selective effect of agriculture spreading on the predisposition to develop CD. Despite the availability of reliable serological tests, e.g., the anti-transglutaminase and antiendomysial antibodies, gray areas of CD diagnosis are increasingly encountered in clinical practice. The diagnostic process must take into consideration the antibody level. The small intestinal biopsy is not the gold standard but one of the important investigations of the diagnostic paraphernalia. New evidence-based guidelines for CD diagnosis are urgently needed for both children and adults.

Mean platelet volume could be a promising biomarker to monitor dietary compliance in celiac disease

BACKGROUND

Celiac disease (CD) is an autoimmune disease that develops in patients with a genetic predisposition, incurring a susceptibility to gluten-containing foods such as barley, wheat, and rye. The elimination of gluten from the diet is the main therapeutic approach and usually leads to clinical and laboratory improvement. There are no ideal markers that objectively assess dietary compliance in CD patients.

MATERIALS AND METHODS

Sixty newly diagnosed CD patients (male/female: 43/17) and 40 healthy subjects (male/female: 23/17) were enrolled in this study. The diagnosis of CD was established by both histological findings of duodenum biopsy (total villous atrophy and lymphocytic infiltration) and positive antibodies against endomysium or gliadin.

RESULTS

A significantly higher mean platelet volume (MPV) was observed in the CD group compared with healthy subjects (8.45 ± 0.96 fL versus 7.93 ± 0.63 fL; p = 0.004). After introduction of a gluten-free diet, the MPV of CD patients in the dietary adherent group was significantly lower than that of the non-adherent group (8.09 ± 0.6 fL versus 8.9 ± 1.08 fL; p = 0.001). Overall dietary adherence rate was 71.6% (43/60 CD patients). In the dietary compliant group, initiation of gluten-free diet was associated with a significant decrease in MPV from base-line values (8.56 fL versus 8.25 fL; p = 0.008). In the non-adherent group, MPV on 3-month follow-up was higher than at base-line (8.05 fL versus 8.91 fL; p = 0.001).

CONCLUSION

MPV could be a promising and easily available biomarker for monitoring of dietary adherence in CD patients at a low cost in comparison with other modalities.

Incidence of celiac disease among second-generation immigrants and adoptees from abroad in Sweden: evidence for ethnic differences in susceptibility

BACKGROUND AND AIMS

The incidence of celiac disease (CD) shows large, worldwide variation. However, whether its causes are environmental (gluten-containing diet) or genetic (specific haplotype) have not been established. The aim of the present study is to examine the incidence of CD among second-generation immigrants and adoptees from abroad to disentangle genetic/ethnic versus environmental influences (assuming that immigrants have similar gluten exposures to native Swedes, and thus differ from them only in terms of their genetic background).

METHODS

Second-generation immigrants and adoptees from abroad were identified in the MigMed 2 Database and were followed until diagnosis of CD, death, or the end of study. Standardized incidence ratios (SIRs) were calculated among these immigrants with native Swedes as the reference group.

RESULTS

A total of 1,050,569 children were defined as second-generation immigrants and the overall SIR of CD (SIR = 0.89, 95% confidence interval 0.84-0.94) was significantly lower than that of native Swedes. The incidence of CD among children with parents from Western, Eastern, and Northern European countries was similar to that in native Swedes, but was lower for those with parents from low-prevalence countries, especially Eastern and Southeast Asian countries. A total of 51,557 children born in foreign countries were adopted by Swedes. Adoptees from Eastern Asia had a significantly decreased SIR of CD.

CONCLUSIONS

The decreased incidence of CD in second-generation immigrants and some groups of adoptees from abroad strongly suggests that ethnic genetic heterogeneity may contribute to the worldwide variation in CD incidence.

Is hyperhomocysteinemia relevant in patients with celiac disease?

AIM: To investigate whether this might be related to the presence of hyperhomocysteinemia.

METHODS: From January 1998 to December 2008, we evaluated the presence of hyperhomocysteinemia in a series of 165 adult celiac disease (CD) patients (138 females and 27 males, mean age 43 years).

RESULTS: Hyperhomocysteinemia was evident in 32 patients (19.3%), although most of them had moderate levels (mean value 25 mcg/ml; range 15-30). Only one patient had a history of myocardial infarction (heterozygosis for N5-N10-metil tetrahydrofolate reductase mutation).

CONCLUSION: The systematic assessment of hyperhomocysteinemia seems, at present, unjustified in CD patients.

Shared genetics in coeliac disease and other immune-mediated diseases

Identifying disease-associated variants can improve the predictive models of disease risk and provide mechanistic insights into disease development. Coeliac disease (CD) is the only autoimmune trait with a known environmental trigger, which makes it an excellent model for studying the complexity of genetic and environmental factors in the development of autoimmunity. In this review, we will focus on the genetic loci that have recently been associated with CD and that contain genes involved in innate and adaptive immunity. Some of these loci are shared with other immune-mediated diseases, suggesting an overlap of the genetic mechanisms involved in the development of such diseases. Some therapies, e.g. tumour necrosis factor inhibitors or a gluten-free diet, are already proving effective for more than one autoimmune disease. Follow-up of individuals with a high genetic risk of CD and other autoimmune diseases could help to elucidate the role of environmental factors (such as infectious agents or alterations in the microbiome) and prevent disease development.

Improved xenobiotic metabolism and reduced susceptibility to cancer in gluten-sensitive macaques upon introduction of a gluten-free diet

BACKGROUND

A non-human primate (NHP) model of gluten sensitivity was employed to study the gene perturbations associated with dietary gluten changes in small intestinal tissues from gluten-sensitive rhesus macaques (Macaca mulatta).

METHODOLOGY

Stages of remission and relapse were accomplished in gluten-sensitive animals by administration of gluten-free (GFD) and gluten-containing (GD) diets, as described previously. Pin-head-sized biopsies, obtained non-invasively by pediatric endoscope from duodenum while on GFD or GD, were used for preparation of total RNA and gene profiling, using the commercial Rhesus Macaque Microarray (Agilent Technologies),targeting expression of over 20,000 genes.

PRINCIPAL FINDINGS

When compared with normal healthy control, gluten-sensitive macaques showed differential gene expressions induced by GD. While observed gene perturbations were classified into one of 12 overlapping categories--cancer, metabolism, digestive tract function, immune response, cell growth, signal transduction, autoimmunity, detoxification of xenobiotics, apoptosis, actin-collagen deposition, neuronal and unknown function--this study focused on cancer-related gene networks such as cytochrome P450 family (detoxification function) and actin-collagen-matrix metalloproteinases (MMP) genes.

CONCLUSIONS/SIGNIFICANCE

A loss of detoxification function paralleled with necessity to metabolize carcinogens was revealed in gluten-sensitive animals while on GD. An increase in cancer-promoting factors and a simultaneous decrease in cancer-preventing factors associated with altered expression of actin-collagen-MMP gene network were noted. In addition, gluten-sensitive macaques showed reduced number of differentially expressed genes including the cancer-associated ones upon withdrawal of dietary gluten. Taken together, these findings indicate potentially expanded utility of gluten-sensitive rhesus macaques in cancer research.

Coagulopathy as initial manifestation of concomitant celiac disease and cystic fibrosis: a case report

Introduction

Celiac disease and cystic fibrosis have many common manifestations, such as malabsorption, steatorrhea and growth failure, and were for many years recognized as one clinical entity. Since their recognition as two separate diseases, their co-existence in a patient has been described sporadically; around 20 cases have been described in the literature. Taking into consideration the incidences of the two diseases, the chance of them occurring together is one in 2,000,000 in the general population.

Case presentation

We describe the case of a five-year-old boy of Turkish ethnicity with both celiac disease and cystic fibrosis, who presented initially with a skin hemorrhage. The diagnosis of celiac disease was made with a positive serum anti-tissue transglutaminase antibody test and the presence of HLA-DQ2 heterodimer, and confirmed on histology with small intestinal villous atrophy. A positive sweat test confirmed the diagnosis of associated cystic fibrosis.

To the best of our knowledge there has been no previous report of this rare presentation of associated celiac disease and cystic fibrosis.

Conclusion

The clinical significance of this case is the consideration of malabsorption with both celiac disease and cystic fibrosis in patients who present with unexplained coagulopathy.

Epidemiology of cancer of the small intestine

Cancer of the small intestine is very uncommon. There are 4 main histological subtypes: adenocarcinomas, carcinoid tumors, lymphoma and sarcoma. The incidence of small intestine cancer has increased over the past several decades with a four-fold increase for carcinoid tumors, less dramatic rises for adenocarcinoma and lymphoma and stable sarcoma rates. Very little is known about its etiology. An increased risk has been noted for individuals with Crohn’s disease, celiac disease, adenoma, familial adenomatous polyposis and Peutz-Jeghers syndrome. Several behavioral risk factors including consumption of red or smoked meat, saturated fat, obesity and smoking have been suggested. The prognosis for carcinomas of the small intestine cancer is poor (5 years relative survival < 30%), better for lymphomas and sarcomas, and best for carcinoid tumors. There has been no significant change in long-term survival rates for any of the 4 histological subtypes. Currently, with the possible exceptions of obesity and cigarette smoking, there are no established modifiable risk factors which might provide the foundation for a prevention program aimed at reducing the incidence and mortality of cancers of the small intestine. More research with better quality and sufficient statistical power is needed to get better understanding of the etiology and biology of this cancer. In addition, more studies should be done to assess not only exposures of interest, but also host susceptibility.