SMALL-INTESTINAL AND GASTRIC ABNORMALITIES IN ULCERATIVE COLITIS

Environmental perception and control of gastrointestinal immunity by the enteric nervous system

The enteric nervous system (ENS) forms a versatile sensory system along the gastrointestinal tract that interacts with most cell types in the bowel. Herein, we portray host-environment interactions at the intestinal mucosal surface through the lens of the enteric nervous system. We describe local cellular interactions as well as long-range circuits between the enteric, central, and peripheral nervous systems. Additionally, we discuss recently discovered mechanisms by which enteric neurons and glia respond to biotic and abiotic environmental changes and how they regulate intestinal immunity and inflammation. The enteric nervous system emerges as an integrative sensory system with manifold immunoregulatory functions under both homeostatic and pathophysiological conditions.

Intestinal Phospholipid Disequilibrium Initiates an ER Stress Response That Drives Goblet Cell Necroptosis and Spontaneous Colitis in Mice

BACKGROUND & AIMS

Patients with ulcerative colitis have low concentrations of the major membrane lipid phosphatidylcholine (PC) in gastrointestinal mucus, suggesting that defects in colonic PC metabolism might be involved in the development of colitis. To determine the precise role that PC plays in colonic barrier function, we examined mice with intestinal epithelial cell (IEC)-specific deletion of the rate-limiting enzyme in the major pathway for PC synthesis: cytidine triphosphate:phosphocholine cytidylyltransferase-α (CTα^IKO mice).

METHODS

Colonic tissue of CTα^IKO mice and control mice was analyzed by histology, immunofluorescence, electron microscopy, quantitative polymerase chain reaction, Western blot, and thin-layer chromatography. Histopathologic colitis scores were assigned by a pathologist blinded to the experimental groupings. Intestinal permeability was assessed by fluorescein isothiocyanate-dextran gavage and fecal microbial composition was analyzed by sequencing 16s ribosomal RNA amplicons. Subsets of CTα^IKO mice and control mice were treated with dietary PC supplementation, antibiotics, or 4-phenylbutyrate.

RESULTS

Inducible loss of CTα in the intestinal epithelium reduced colonic PC concentrations and resulted in rapid and spontaneous colitis with 100% penetrance in adult mice. Colitis development in CTα^IKO mice was traced to a severe and unresolving endoplasmic reticulum stress response in IECs with altered membrane phospholipid composition. This endoplasmic reticulum stress response was linked to the necroptotic death of IECs, leading to excessive loss of goblet cells, formation of a thin mucus barrier, increased intestinal permeability, and infiltration of the epithelium by microbes.

CONCLUSIONS

Maintaining the PC content of IEC membranes protects against colitis development in mice, showing a crucial role for IEC phospholipid equilibrium in colonic homeostasis. SRA accession number: PRJNA562603.

Molecular Changes in the Non-Inflamed Terminal Ileum of Patients with Ulcerative Colitis

Ulcerative colitis is a chronic inflammatory disease confined to the colon. Although the etiopathogenesis remains unknown, small bowel dysfunctions like histological and permeability alterations have been described in ulcerative colitis. We evaluated the molecular gene signature in the non-inflamed terminal ileum of 36 ulcerative colitis patients (7 active, with Mayo endoscopic subscore ≥2, and 29 inactive) as compared to 15 non-inflammatory bowel disease controls. Differential gene expression analysis with DESeq2 showed distinct expression patterns depending on disease activity and maximal disease extent. We found 84 dysregulated genes in patients with active extensive colitis and 20 in inactive extensive colitis, compared to controls. There was an overlap of 5 genes: REG1B, REG1A, MUC4, GRAMD2, and CASP10. In patients with left-sided colitis, ileal gene expression levels were similar to controls. Based on gene co-expression analysis, ileal changes in active ulcerative colitis patients were related to immune functions. The ileal changes in the inactive ulcerative colitis subjects converged into the maintenance of the intestinal barrier through increased mitochondrial function and dampened immune functions. In conclusion, we identified molecular changes in the non-inflamed ileum of ulcerative colitis that are dependent on colonic inflammation.

Prevalance of Celiac Disease in Patients with Inflammatory Bowel Disease in Turkish Population

Background

Celiac disease (CD) and inflammatory bowel disease (IBD) involve inflammation of the gastrointestinal lumen, which environmental, genetic, and immunological factors have a role in their pathogenesis. The prevalence of celiac disease in IBD ranges from 0% to 14%. In this study, our aim was to determine the prevalence of CD in IBD patients followed by us who are attending the hospital or outpatient clinic over a period of time of seven years.

Methods

Seven hundred and fifty nine patients (425 M, 334 F, mean age: 46.75, 396 ulcerative colitis (UC), 363 Crohn's disease (CrD)) diagnosed and followed up for IBD between January 2009 and July 2016 were evaluated retrospectively, and clinical, demographic, laboratory, and endoscopic data were collected.

Results

CD was investigated in 79 (%10.4) inflammatory bowel disease patients according to symptoms, and in 5.06% (n = 4) of them, we diagnosed CD. The most common indication for investigating for CD was iron deficiency anemia unreponsive to iron supplementation.

Conclusions

We did not find an increased prevalance of celiac disease in Turkish IBD patients in this study. In the presence of refractory iron deficiency anemia without any other cause in IBD patients, investigations for celiac disease should be considered.

Link Between Celiac Disease and Inflammatory Bowel Disease

GOAL

The aim of this analysis was to assess in patients with inflammatory bowel disease (IBD) the risk of celiac disease and in celiac disease patients the risk of IBD.

BACKGROUND

Previous studies report a possible association between IBD and celiac disease; however, this link is controversial.

STUDY

Using the search terms "inflammatory bowel disease" and "celiac disease," we identified initially 1525 publications. In total 27 studies met inclusion criteria. Proportions and 95% confidence intervals (CIs) for the prevalence of IBD in celiac disease and vice versa were compared with published prevalence rates for the respective geographic regions.

RESULTS

We included 41,482 adult IBD patients (20,357 with Crohn's disease; 19,791 with ulcerative colitis; and 459 patients with celiac disease). Overall, in IBD patients the prevalence of celiac disease was 1110/100,000 (95% CI, 1010-1210/100,000) as compared with a prevalence of 620/100,000 (95% CI, 610-630/100,000) in the respective populations (odds ratio, 2.23; 95% CI, 1.99-2.50). In contrast, in patients with celiac disease, 2130/100,000 had IBD (95% CI, 1590-2670/100,000) as compared with 260/100,000 (95% CI, 250/100,000-270/100,000) in the respective populations (odds ratio, 11.10; 95% CI, 8.55-14.40). This effect was not different for ulcerative colitis and Crohn's disease. Although there was no evidence for publication bias for celiac disease in IBD, the funnel plot suggested that the association between IBD in celiac disease might be influenced by publication bias.

CONCLUSIONS

The data are consistent with the notion that celiac disease is a risk factor for IBD and to lesser degree patients with IBD have an increased risk of celiac disease.

Impairment of Small Intestinal Function in Ulcerative Colitis: Role of Enteric Innervation

Small intestinal dysfunction has been described in patients with ulcerative colitis and in experimental animal models of colitis. This is demonstrated by a decrease in fluid, electrolyte, amino acid, fat and carbohydrate absorption as well as by deranged intestinal motility. Histopathological changes in the small intestines in colitis have not been consistently demonstrated, but there is evidence of structural and biochemical alterations as shown by increased intestinal permeability and a decrease in the expression of multiple brush border membrane enzymes such as disaccharidases and aminopetidases, in both humans and experimental animals. The pathophysiology of this dysfunction has not been elucidated, but it is thought to include alterations in neural circuitry such as increased neuronal excitability, neuronal damage and changes of neuropeptidergic innervation and receptors as well as an increase in local production of pro-inflammatory cytokines and alterations in the production of some neurohumoral mediators. In the following, we provide an update on the advancement of clinical and scientific contributions to elucidate the underlying mechanisms of the alteration of the functions of apparently intact small intestinal segments, induced by ulcerative colitis.

Increased Proliferation of the Ileal Epithelium as a Remote Effect of Ulcerative Colitis

BACKGROUND

Aside from cases of backwash ileitis, the ileal mucosa of patients with ulcerative colitis (UC), an idiotypic inflammatory bowel disease, has received little attention despite the fact that colitis is known to trigger alterations in morphology and/or functions of the small intestine remotely.

METHODS

The ileal mucosa was studied in patients with UC and in a spontaneous model of colitis (Il10/Nox1 mice) mimicking the histological and clinical features of UC and was also studied in acute and chronic murine models of chemically induced colitis. Proliferation and apoptosis were assessed using morphological and immunohistological methods and Western blot analysis. Peyer's patch immune cell subsets were analyzed. Cytokines levels were quantified using quantitative PCR and Luminex xMAP technology. Total RNA from isolated ileal crypts was used for whole genome transcriptome analysis.

RESULTS

The most striking features were an increased ileal crypt length associated with an enhanced cell proliferation of the transit-amplifying cells along with activation of the Wnt/β-catenin and MAPkinase pathways. These changes did not result from intestinal inflammation as assessed by histology and/or pro-inflammatory cytokine expression levels. The increased proliferation rate was dependent on the duration but not on the severity of colitis and was observed in different mouse models of colitis, including the Il10/Nox1 model and 2,4,6-trinitrobenzenesulfonic acid-treated mice. Interestingly, the ileal mucosa of patients with UC also displayed longer crypts and enhanced cell proliferation compared with control patients.

CONCLUSIONS

These data show that despite the absence of inflammation in the small intestine, alterations in the ileal mucosa homeostasis are present in UC.

Celiac disease, collagenous sprue and microscopic colitis in IBD. Observations from a population-based cohort of IBD (ICURE)

OBJECTIVE

Inflammatory bowel disease (IBD), microscopic colitis and celiac disease are all diseases with worldwide distribution and increased incidence has been reported from many areas. There is a shortage of studies investigating the occurrence of these diseases in the same individual and whether those affected demonstrate any particular phenotype. The aim of the study was to describe the concomitant incidence of microscopic colitis and celiac disease in a population-based IBD cohort.

METHODS

All 790 individuals in a prospective population-based cohort included 2005-09 from Uppsala region, Sweden, were reviewed regarding the appearance of microscopic or celiac disease before or after IBD diagnosis.

RESULTS

Fifty percent (396/790) of the patients had been examined for the possibility of celiac disease. Seventeen patients with celiac disease were found, representing 2.2% of the cohort. Patients with celiac disease were younger compared to the non-celiac patients and those with colitis had more often an extensive inflammation of the colon. Seventy-one percent (12/17) were women. The majority of the patients were diagnosed with celiac disease before IBD. Five patients with IBD had an earlier diagnosis of microscopic colitis or developed it after the IBD diagnosis. One teenager developed collagenous sprue, misinterpreted as a severe relapse of ulcerative colitis (UC) resulting in colectomy.

CONCLUSIONS

The risk for celiac disease seems not to be increased in IBD, but those affected by both diseases seem to be predominantly women with extensive UC. There is a potential association between microscopic colitis and IBD.

Electrocautery-induced localized colonic injury elicits increased levels of pro-inflammatory cytokines in small bowel and decreases jejunal alanine absorption

BACKGROUND

Colitis is associated with functional abnormalities in proximal non-inflamed gut areas, but animal models to study small bowel dysfunction in colitis have limitations. This study aims to determine small intestinal alanine absorption and cytokine expression in a novel model of colonic ulceration induced by electro-cautery.

METHODS

A descending colon ulcer was induced in rats by a bipolar electro-cautery probe. Ulcer score was determined using Satoh's criteria. Jejunal alanine absorption was measured immediately and at different time intervals post ulcer induction. Levels of interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) protein and m-RNA were determined in mucosal scrapings obtained from the colon, duodenum, jejunum and ileum at various time intervals after colonic ulcer induction.

RESULTS

The mean ulcer score was 3 up to 48h, followed by healing by 96h post ulcer induction. Small bowel histology was normal throughout. Jejunal alanine absorption was reduced by 12-34% immediately and up to 72h after cautery and returned to normal at 96h. IL-1 and TNF-α mRNA increased significantly in the colon, duodenum, jejunum and ileum 3h post electro-cautery and returned to normal at 48h, while that of IL-6 increased significantly at 48h post ulcer induction. Similarly, IL-1, IL-6 and TNF-α protein levels increased in the duodenum, jejunum, ileum and colon up to 48h post ulcer induction.

CONCLUSIONS

Electrically induced localized colonic injury increased production of pro-inflammatory cytokines in non-inflamed segments of the small intestine and was associated with derangements of jejunal absorptive function.

Serologic celiac disease in patients with inflammatory bowel disease

BACKGROUND

There is an association of celiac disease (CD) with several gastrointestinal illnesses. We aimed to determine the prevalence of CD in patients with inflammatory bowel disease (IBD) to evaluate the value of the routine serological tests for CD in these patients.

MATERIALS AND METHODS

patients with IBD underwent screening test for CD. The screening test was based on IgA anti-tTG antibody evaluated by ELISA method and IgA EMA (endomysial antibody) measured by the indirect immunofluorescence method. Fisher exact and chi-square and t tests were used for data analysis.

RESULTS

the study was conducted on 100 patients, with a mean age of 34.74 ± 12.03 (SD) years. The mean simplified Crohn's disease activity index was 90 ± 17 (SE) and the mean colitis activity index was 3.46± 0.96 (SE). Seventeen patients (17%) had IgA anti-tTG antibody levels above the cutoff point (> 20). Thirty-two patients were positive for IgA EMA. IgA EMA was positive in nine IgA anti-tTG positive patients (three patients with Crohn's Disease and six ones with ulcerative colitis). Then, the prevalence of serologic CD was 9% that was higher than that of general population. A significant correlation was found between the results of IgA EMA and those of IgA anti-tTG (P=0.001) whereas Fisher exact test revealed significant difference between frequency distribution of positive and negative results of IgA EMA and IgA anti-tTG in patients with ulcerative colitis and Crohn's disease (P=0).

CONCLUSION

the prevalence of serologic CD in general population in Iran has been reported to be 0.6-0.96%. Then, its prevalence in our sample size was about ten times more than that in general population.

Increased CD8+ intraepithelial lymphocyte infiltration and reduced surface area to volume ratio in the duodenum of patients with ulcerative colitis

OBJECTIVE

Recent evidence suggests the involvement of the upper gastrointestinal tract in ulcerative colitis (UC). By conducting a prospective controlled study, we explored the immunological abnormalities in the duodenal mucosa of UC patients.

METHODS

Duodenal and colonic biopsies were collected from 24 corticosteroid-free UC patients and 21 controls. Colonization by Helicobacter pylori and positivity for anti-endomysial antibodies was an exclusion criteria. The severity of duodenal and colonic inflammation was determined by endoscopic and histologic scores. Morphometry was performed to measure the surface area to volume ratio (SV). Duodenal CD3(+) and CD8(+) intraepithelial lymphocytes (IELs) and lamina propria mononuclear cells (LPMCs) were detected by immunohistochemistry.

RESULTS

Fifteen UC patients and 14 controls were Helicobacter pylori and anti-endomysial antibody negative and were thus included in the study. Microscopic duodenitis was reported in 4 of the 15 UC patients (26.6%), and in none of the controls. A significantly higher number of CD3(+) and CD8(+) IELs and LPMCs was found in UC patients than in controls. A significant positive correlation between the percentage of both CD3(+) and CD8(+) IELs and disease activity was found in UC patients. SV was significantly reduced in UC patients compared to controls, and inversely correlated with the percentage of CD8(+) IELs.

CONCLUSIONS

The duodenum of UC patients is infiltrated by a higher number of CD8(+) IELs which correlates with the degree of villous flattening and disease activity, but not with extent of the colonic lesions. Further studies are needed to clarify whether the duodenum is a target organ in UC.

Even low-grade inflammation impacts on small intestinal function

Independent of the cause and location, inflammation - even when minimal - has clear effects on gastrointestinal morphology and function. These result in altered digestion, absorption and barrier function. There is evidence of reduced villus height and crypt depth, increased permeability, as well as altered sugar and peptide absorption in the small intestine after induction of inflammation in experimental models, which is supported by some clinical data. Identification of inflammatory factors which may promote the process of gastrointestinal dysfunction as well as clinical research to verify experimental observations of inflammatory modulation of gastrointestinal function are required. Moreover, nutritional strategies to support functional restitution are needed.

Morphological and biochemical alterations in the jejunum following iodoacetamide-induced colitis in rats

This study aims to describe the morphological alterations in the small and large intestines as well as the expression of some enterocyte enzymes and carriers in a rat model of iodoacetamide-induced colitis. Biopsies from the large and small intestines were taken at 1, 2, 4, 8, and 16 days postinduction and studied by light microscopy. The expressions of lactase, sucrase, aminopeptidase, and Glut-5 in the jejunum were studied by immunohistochemistry. Gene expressions of enterocyte lactase and sucrase were determined by RT-PCR using specific oligonucleotides. Microscopic examination of the large intestines revealed manifestations concordant with inflammation. Such alterations peaked at 2 days, were maintained to a lesser extent for 4 days, regressed by 8 days, and healed by 16 days. In the jejunum, the expression of lactase, sucrase, and aminopeptidase decreased 2 days after colitis induction, and recovered 2 days later. Similarly, Glut-5 expression decreased transiently with partial recovery by day 8. Compared with sham, gene expression of jejunal brush border enzymes sucrase and lactase showed a 4-fold increase in lactase and a 9-fold increase in sucrase after 4 days. We conclude that colitis can induce significant functional abnormalities in distant noninflamed small bowel regions.

Localized colonic inflammation increases cytokine levels in distant small intestinal segments in the rat

Local inflammation in the colon has been associated with nutrient malabsorption and altered motility in the small bowel. These remote effects suggest the release of mediators which can act (or alter) the function of intestinal segments located far from the primary area of inflammation. This study describes the changes in the expression of pro-inflammatory cytokines in the colon and in various segments of the small intestine in two rat models of experimental colitis. Colitis was induced by the intracolonic administration of 100 microL of 6% iodoacetamide or 250 microL of 2, 4, 6-trinitrobenzene sulfonic acid. Levels of interleukin one beta, interleukin 6, and tumor necrosis factor alpha were measured by ELISA in tissue homogenate sampled from duodenum, jejunum, ileum and colon at different time intervals. In homogenates of strips isolated from duodenum, jejunum and ileum, tumor necrosis alpha and interleukin-6, increased significantly 3-6 h after iodoacetamide or TNBS administration and remained elevated until the colonic inflammation subsided. Interleukin one beta showed comparable but delayed increase. Similar, but more pronounced increase of the three cytokines was noticed in areas of the colon adjacent to the ulcer. Histologic examinations revealed important inflammatory changes in the colon; however, examination of sections from the small intestines did not reveal significant differences between controls and rats with colitis. In conclusion, expression of pro-inflammatory cytokines is increased in remote segments of the small intestines during colitis. The findings may provide a partial explanation or a molecular substrate for the associated small bowel dysfunction.

Pre-pouch ileitis: a disease of the ileum in ulcerative colitis after restorative proctocolectomy

OBJECTIVE

Ileal inflammation in ulcerative colitis can occur as backwash ileitis or prestomal ileitis. After restorative proctocolectomy (RPC), ileal inflammation may be present in the pouch (pouchitis) but inflammation proximal to the pouch in the neo-terminal ileum, so called pre-pouch ileitis (PI), has also been observed. As pouchitis is increasingly common and PI can mimic it, our aim was to characterize this condition.

SUBJECTS AND METHODS

A review of prospectively collected data on 571 inflammatory bowel disease patients undergoing follow-up after RPC in a single centre over 22 years was performed. The histology of biopsy material was reviewed and staining for colonic mucosal phenotypic changes was undertaken. It was not routine practice to prospectively assess all patients for pre-pouch ileitis when the database was constructed.

RESULTS

Of 19 patients with inflammation of the pre-pouch neo-terminal ileum (NTI) identified three had Crohn's disease and one a NSAID stricture. The remaining 15 had a characteristic diffuse inflammation extending from the NTI-pouch junction proximally: pre-pouch ileitis. The inflammation extended proximally for up to 50 cm. Fistula formation was seen in only one. Seven (47%) of 15 had pouchitis but only two had suffered backwash ileitis pre-operatively. Seven responded to medical therapy and four to surgery. The histological appearances including staining for colonic phenotypic change were similar in PI and pouchitis.

CONCLUSION

Pre-pouch ileitis is uncommon. As the patients' previous diagnosis of UC was confirmed and there was no radiological or histological evidence of Crohn's disease, PI appears to have a distinct pathogenesis from Crohn's disease.

Inhibitory effect of experimental colitis on fluid absorption in rat jejunum: role of the enteric nervous system, VIP, and nitric oxide

Impairment of small intestinal absorption has been described in patients with ulcerative colitis and in animal models of experimental colitis. The pathophysiology of this dysfunction has not been elucidated. The aim of this study was to investigate the effect of chemical colitis on jejunal fluid absorption and determine the role of the enteric nervous system and some putative neurotransmitters. In a rat model of iodoacetamide-induced colitis, jejunal net fluid absorption was evaluated by the in vivo single-pass perfusion technique. The effects of 1) tetrodotoxin (TTX), 2) benzylalkonium chloride (BAC), 3) capsaicin, 4) vasoactive intestinal polypeptide (VIP) antagonism, 5) nitric oxide (NO) synthase (NOS) inhibition, and 6) 5-hydroxytryptamine type 3 and 4 (5-HT(3) and 5-HT(4)) receptor antagonism on the changes in fluid movement were investigated. A significant decrease in jejunal net fluid absorption was found 2 and 4 days after colitis induction: 26 (SD 14) and 28 (SD 19) microl x min(-1) x g dry intestinal wt(-1), respectively [P < 0.0002 compared with sham rats at 61 (SD 6.5) microl x min(-1) x g dry intestinal wt(-1)]. No histological changes were evident in jejunal sections. TTX and BAC reversed this decrease in fluid absorption: 54 (SD 13) and 44 (SD 14) microl x min(-1) x g dry intestinal wt(-1) (P = 0.0005 and P = 0.019, respectively, compared with colitis). Ablation of capsaicin-sensitive primary afferent fibers had a partial effect: 45 (SD 5) microl x min(-1) x g dry intestinal wt(-1) (P = 0.001 and P = 0.003 compared with colitis and sham, respectively). Constitutive and neuronal NOS inhibition and VIP antagonism returned jejunal net fluid absorption to normal values: 66 (SD 19), 61 (SD 5), and 56 (SD 14) microl x min(-1) x g dry intestinal wt(-1), respectively. 5-HT(3) and 5-HT(4) receptor antagonism had no effect. Chemical colitis is associated with a significant decrease in jejunal net fluid absorption. This decrease is neurally mediated and involves VIP- and NO-related mechanisms.

Endoscopy in celiac disease

PURPOSE OF REVIEW

The primary objective of this review is to highlight the evidence for the role of endoscopy in celiac disease.

RECENT FINDINGS

Evidence is presented that the endoscopic markers of celiac disease are specific although not sensitive for the disease. Villous atrophy, the hallmark of celiac disease, is patchy in the duodenum, and various techniques may identify areas of villous atrophy. These methods include magnification endoscopy and chromoendoscopy. The most recent innovation, video capsule endoscopy, may be of value in the diagnosis of celiac disease and in the assessment of patients with complicated celiac disease.

SUMMARY

Endoscopy and duodenal biopsies are the mainstay for diagnosing celiac disease. Although characteristic endoscopic features may be useful, their absence does not exclude celiac disease. Random biopsy, even of normal-appearing mucosa is necessary for the diagnosis of celiac disease.

Inflammatory bowel disease in patients with celiac disease

BACKGROUND

Several case reports and series report an association between celiac disease and inflammatory bowel disease (IBD); however, there is no current data assessing this association. We therefore studied the occurrence of these conditions in a cohort of patients with celiac disease seen at a referral center.

METHODS

A database of patients with celiac disease seen between 1981 and 2002 was analyzed. Only biopsy-proven adults were included. Patients who had endoscopic and pathologic evidence of IBD were identified, and their pathology was reviewed. Age- and sex-adjusted prevalence rate ratios were determined by comparing results with population-based prevalence data.

RESULTS

Among 455 patients with celiac disease, IBD was identified in 10 (5 had ulcerative colitis and 5 had Crohn's disease). This represented an age- and sex-adjusted prevalence rate ratio for ulcerative colitis of 3.56 (95% confidence interval, 1.48-8.56) and for Crohn's disease of 8.49 (95% confidence interval, 3.53-20.42).

CONCLUSION

Within our cohort of patients with celiac disease, IBD was significantly more common than in the general population.

Association of celiac disease with connective tissue diseases and autoimmune diseases of the digestive tract

Celiac disease (CD) is an autoimmune enteropathy triggered by the ingestion of gluten in susceptible individuals, and is one of the most frequent genetically based diseases, with a prevalence of 1:200 in the general population. The association between CD and connective tissue diseases (CTD) and autoimmune diseases of the digestive tract (DT) has been described in several case reports but in few extensive studies, with varying prevalence. A high rate of false positive results were observed when low specific tests, such as the anti-gliadin and the guinea pig tissue transglutaminase (tTG) antibody assays were used. In a study of 400 patients with CTD and 218 with autoimmune DT disease, tested for IgA and IgG anti-tTG using the more specific human recombinant antigen, 12 cases (1.9%) of anti-tTG antibody positivity were found, but only 2 (0.3%) were confirmed as affected by CD following small bowel biopsy. Most of the patients testing false positive had primary biliary cirrhosis. In this short review we describe the association between CD and CTD, inflammatory bowel disease and primary biliary cirrhosis, with special emphasis on the diagnostic accuracy of CD antibody assays.

IgA and IgG tissue transglutaminase antibody prevalence and clinical significance in connective tissue diseases, inflammatory bowel disease, and primary biliary cirrhosis

An association between celiac disease (CD) and other autoimmune diseases such as connective tissue diseases (CTD), inflammatory bowel diseases (IBD), and primary biliary cirrhosis (PBC) has been reported in several studies. However, a high rate of false positives in autoantibody testing was noted, especially when tissue transglutaminase (tTG) from guinea pig liver was used. Thus, the real prevalence of CD in CTD, IBD, and PBC is unclear. In a case-control study, 400 patients with CTD, 170 with IBD, 48 with PBC, and 120 healthy subjects were investigated for CD by the analysis of IgA and IgG tTG antibodies using the more specific human recombinant tTG immunoenzymatic assay. Patients and controls with positive findings were further tested for antiendomysial antibodies by indirect immunofluorescence and HLA typing, and those found positive by either of these tests underwent duodenal biopsy to confirm a possible diagnosis of CD. Twelve patients were positive for IgA or IgG tTG antibodies, showing an overall prevalence of 1.9%. Only 1 healthy subject (0.8%) had a low level positive reaction for IgA anti-tTG. Among the 12 patients and the healthy subject, only 2 (1 SLE and 1 ulcerative colitis patient) were subsequently confirmed to be affected with CD by positive EMA, HLA, and small bowel biopsy findings. The highest rate of false positives was found in PBC patients (10.4%). For these reasons, serological screening testing for CD is not recommended in CTD patients or in subjects affected with IBD or PBC, unless there is a relevant clinical suspicion of CD.

IgA and IgG tissue transglutaminase antibody prevalence and clinical significance in connective tissue diseases, inflammatory bowel disease, and primary biliary cirrhosis

An association between celiac disease (CD) and other autoimmune diseases such as connective tissue diseases (CTD), inflammatory bowel diseases (IBD), and primary biliary cirrhosis (PBC) has been reported in several studies. However, a high rate of false positives in autoantibody testing was noted, especially when tissue transglutaminase (tTG) from guinea pig liver was used. Thus, the real prevalence of CD in CTD, IBD, and PBC is unclear. In a case-control study, 400 patients with CTD, 170 with IBD, 48 with PBC, and 120 healthy subjects were investigated for CD by the analysis of IgA and IgG tTG antibodies using the more specific human recombinant tTG immunoenzymatic assay. Patients and controls with positive findings were further tested for antiendomysial antibodies by indirect immunofluorescence and HLA typing, and those found positive by either of these tests underwent duodenal biopsy to confirm a possible diagnosis of CD. Twelve patients were positive for IgA or IgG tTG antibodies, showing an overall prevalence of 1.9%. Only 1 healthy subject (0.8%) had a low level positive reaction for IgA anti-tTG. Among the 12 patients and the healthy subject, only 2 (1 SLE and 1 ulcerative colitis patient) were subsequently confirmed to be affected with CD by positive EMA, HLA, and small bowel biopsy findings. The highest rate of false positives was found in PBC patients (10.4%). For these reasons, serological screening testing for CD is not recommended in CTD patients or in subjects affected with IBD or PBC, unless there is a relevant clinical suspicion of CD.

Simultaneous presentation of coeliac disease and ulcerative colitis in a child

Coeliac disease and inflammatory bowel disease (IBD) individually are not uncommon in children, but the occurrence of both conditions together is rare. The combined presentation of coeliac disease and IBD in a girl of 7 years is presented with a review of the related literature. The occurrence of coeliac disease with IBD should be considered at the time of diagnosis and at relapse, or where there is difficulty maintaining remission in established IBD. Screening with serum antibody tests may be helpful.

Intestinal absorption of ursodeoxycholic acid in children and adolescents with inflammatory bowel disease

BACKGROUND

Ursodeoxycholic acid absorption in the proximal intestine may be impaired in patients with inflammatory bowel disease.

METHODS

We examined the intestinal absorption of ursodeoxycholic acid by the oral ursodeoxycholic acid tolerance test in 19 children and adolescents with inflammatory bowel disease at various stages, including 8 patients with unoperated Crohn's disease, 3 patients with ileal-resected Crohn's disease, 8 with ulcerative colitis, and 8 healthy control subjects.

RESULTS

Ursodeoxycholic acid malabsorption was present in all patients with unoperated Crohn's disease in the first diagnosed active stage, in 3 of 5 patients in a relapsing active stage, and in 2 of 8 patients in remission. Ursodeoxycholic acid absorption was significantly lower in patients in the first diagnosed active stage than in the healthy controls (p < 0.01) or in patients in remission (p < 0.01). There was no significant difference between healthy controls and the patients in a relapsing active stage or in remission. Ursodeoxycholic acid absorption was abnormal during the first postoperative month in patients with ileal-resected Crohn's disease, but normalized over time. Malabsorption of ursodeoxycholic acid was not observed in any patients with ulcerative colitis.

CONCLUSIONS

These findings suggest that absorption of ursodeoxycholic acid in the proximal intestine is impaired in patients with Crohn's disease and that the oral ursodeoxycholic acid tolerance test is a convenient and useful means of evaluating the absorption of bile acid in the proximal intestine in pediatric patients with ileal or ileocolic Crohn's disease.

Dermatitis herpetiformis associated with ulcerative colitis

Over the past 20-years, it has been shown that the majority of patients with dermatitis herpetiformis (D.H.) suffer from coeliac disease of varying intensity. Dermatitis herpetiformis may also be associated with other autoimmune diseases but only exceptionally with chronic ulcerative colitis (U.C.).

Adult coeliac disease within a defined geographic area in Sweden. A study of prevalence and associated diseases

An epidemiologic study of coeliac disease in a geographically defined area of Sweden showed that the prevalence was 95.5/10(5) inhabitants aged 15 years or more. The highest prevalence, 178/10(5) inhabitants, was found in the age group 65-74 years. The lowest prevalence, 39/10(5) inhabitants, was found in patients aged 15-24 years. Among the associated diseases an especially high incidence of associated thyroid disease was observed: thyrotoxicosis occurred in 5.0% and hypothyroidism in 5.8% of the patients.

Coeliac proctitis

An increased association of ulcerative colitis and coeliac disease has been reported, as have the results of several small-bowel biopsy studies in ulcerative colitis. Forty-two patients from a population of 438 patients with coeliac disease had rectal biopsies. Fourteen of these showed inflammation of various degrees of severity, including three compatible with a diagnosis of ulcerative colitis. The presenting complaint in 34 of these patients was diarrhoea or steatorrhoea. Twenty-seven patients had coeliac disease diagnosed at the same time or after their rectal biopsy. The other 15 were previously diagnosed coeliacs. Twelve of the 14 patients with abnormal rectal biopsy specimens were known to have subtotal/total villous atrophy at the time of rectal biopsy. Proctitis as seen in these coeliac patients had no unique features to differentiate it from proctitis caused by other disorders. The diarrhoea/steatorrhoea stopped in all patients on commencement of a gluten-free diet, except in those with ulcerative colitis. Proctitis is common in patients with coeliac disease presenting with diarrhoea/steatorrhoea. This study supports the finding of an increased association of coeliac disease and ulcerative colitis and is, to our knowledge, the first rectal biopsy study of a coeliac population.

Zinc absorption in inflammatory bowel disease

Zinc absorption was measured in 29 patients with inflammatory bowel disease and a wide spectrum of disease activity to determine its relationship to disease activity, general nutritional state, and zinc status. Patients with severe disease requiring either supplementary oral or parenteral nutrition were excluded. The mean 65ZnCl2 absorption, in the patients, determined using a 65Zn and 51Cr stool-counting test, 45 +/- 17% (SD), was significantly lower than the values, 54 +/- 16%, in 30 healthy controls, P less than 0.05. Low 65ZnCl2 absorption was related to undernutrition, but not to disease activity in the absence of undernutrition or to zinc status estimated by leukocyte zinc measurements. Mean plasma zinc or leukocyte zinc concentrations in patients did not differ significantly from controls, and only two patients with moderate disease had leukocyte zinc values below the 5th percentile of normal. In another group of nine patients with inflammatory bowel disease of mild-to-moderate severity and minimal nutritional impairment, 65Zn absorption from an extrinsically labeled turkey test meal was 31 +/- 10% compared to 33 +/- 7% in 17 healthy controls, P greater than 0.1. Thus, impairment in 65ZnCl2 absorption in the patients selected for this study was only evident in undernourished persons with moderate or severe disease activity, but biochemical evidence of zinc deficiency was uncommon, and clinical features of zinc depletion were not encountered.

Microscopic colitis-a cause of chronic watery diarrhoea

Six patients with severe watery diarrhoea were found to have microscopic total colitis. None had any abnormality detectable by conventional tests used to diagnose inflammatory bowel disease-namely, barium radiology and endoscopy. The diagnosis could only be made by microscopic examination of biopsy specimens from the apparently normal colon. Anaemia, raised erythrocyte sedimentation rate, hypokalaemia, and hypoalbuminaemia were common findings. Small-bowel function was normal in all, though three patients had jejunal lesions of uncertain relevance but seemingly unrelated to the diarrhoea. The five patients given anti-inflammatory drugs showed a satisfactory response with improvement of the diarrhoea and colonic inflammation and return to normal of the abnormal laboratory findings. Microscopic colitis is responsible for a proportion of cases of intractable diarrhoea of obscure origin and rectal and colonic biopsies sould be undertaken in such cases.

Chronic inflammatory bowel disease in patients with coeliac disease

Six patients with coeliac disease and inflammatory bowel disease are described. Of special interest were two patients with coeliac disease and dermatitis herpetiformis and ulcerative colitis, one of whom also had sclerosing cholangitis. Three patients had both coeliac disease and ulcerative colitis, and one of them also had sclerosing cholangitis. In one patient with coeliac disease Crohn's disease of the small bowel was diagnosed. There seems to be association between coeliac disease without dermatitis herpetiformis, and ulcerative colitis. The possible combination of coeliac disease and inflammatory bowel disease deserves more attention than it has hitherto received.

Diet and health of people with an ileostomy. 2. Ileostomy function and nutritional state

1. Most subjects who have their large intestine removed and an ileostomy formed lead a healthy life after operation, although they are prone to a variety of metabolic problems. In order to determine the factors likely to lead to these metabolic disturbances a detailed assessment of ileostomy output and composition and of dietary intake in relation to nutritional and metabolic status has been made in a group of ileostomy patients living at home.

2. Thirty-six volunteers with established ileostomies (twenty-six ulcerative colitis (UC) patients and ten, Crohn's colitis (CC) patients) made a 24 h collection of urine and ileostomy effluent and kept a 7 d record of dietary intake and the frequency with which they emptied their ileostomy bag. Blood was collected for haematological and biochemical indices of nutritional status and height, weight and skinfold thickness were measured.

3. Effluent output for the whole group was 760±322 g/day (range 273–1612) and was very closely related to effluent sodium output (R 0·98). Stepwise multiple regression analysis of dietary and other variables identified the amount of ileum resected as the main determinant of both effluent output and effluent sodium. The CC group had significantly greater effluent output (1084±340 g/d) compared with the UC patients (635±215g/d) (P< 0·001); and excreted significantly more nitrogen, carbohydrate and sodium than the UC group.

4. The CC patients particularly showed evidence of salt depletion. The mean (±SD) 24 h urine Na loss for CC patients was 31±30 mmol and for UC patients 67±34 mmol (P< 0·01) with five of the ten CC patientsv. four of the twenty-six patients with UC having raised urinary or plasma aldosterone levels.

5. All subjects had normal haematological and biochemical indices of nutritional status in the blood. Height and percentage body fat were also within the normal range when compared with a control population matched for age, sex and occupation, but patients with an ileostomy weighed on average 4·1 kg less than the controls.

6. These studies show that patients with an ileostomy come within the range of the normal population for most nutritional indices although are at increased risk of salt depletion. Effluent volume, which is probably the determining factor in most metabolic complications of ileostomy, is related more to the extent of the small bowel resection than to diet.

Role of sulphasalazine in the aetiology of folate deficiency in ulcerative colitis

Only two (2.5%) of 80 outpatients with histologically proven ulcerative colitis had folate deficiency associated with anaemia or macrocytosis. Mean folate absorption, measured using micrograms/kg body weight of a tritium-labelled physiological folate derivative, 5-methyltetrahydroteroylglutamic acid, in six newly diagnosed patients was 76.7% (normal greater than 95%) but fell to 69.4% after three months' treatment with sulphasalazine. Mean difference in individual patients was 7.5% +/- 5.2% (SD) (p less than 0.02). Mean folate absorption in four patients with megaloblastic anaemia or macrocytosis which developed during treatment with sulphasalazine was 66.3%. This rose to 82.4% after the drug was stopped. Mean difference in individual patients was 16.6 +/- 6.6% (SD) (p less than 0.001). All patients who developed anaemia or macrocytosis with sulphasalazine had additional reasons for folate deficiency. These included coeliac disease, severe nutritional deficiencies, and haemolysis. It was concluded that sulphasalazine impairs folate absorption but this only becomes significant if other reasons for folate deficiency are also present.

The existence of inflammatory bowel lesions in gluten-sensitive enteropathy

Three patients with coincident coeliac disease and inflammatory bowel disease are described. In 2 patients with known coeliac disease the recurrence of diarrhoea was not due to dietary deviation but to an additional large bowel pathology.

Co-existing coeliac and inflammatory bowel disease in a patient with Turner's syndrome

A patient, aged 20, with Turner's syndrome was found to have both coeliac disease and chronic ulcerative colitis. Although a gluten-free diet restored to normal the jejunal biopsy, persisting diarrhoea was found to be due to coexisting left-sided ulcerative colitis. A search of the literature revealed only three detailed reports of chronic inflammatory bowel disease in coeliac patients, one of coeliac disease in Turner's syndrome and three of inflammatory bowel disease in Turner's syndrome. Growth failure with coeliac or inflammatory bowel disease in females, may call for a chromosomal study, even in the absence of webbing of the neck. The reason for three uncommon disorders occurring in this patient remains obscure.

Cytokinetic studies of crypts in convoluted human small-intestinal mucosa

Forty-seven peroral biopsy specimens of duodenojejunal mucosa showing convolutions were obtained from patients with a variety of clinical disorders. These mucosal samples were divided into three groups according to the extent of the convolutions and the severity of the accompanying histopathological changes; the cytokinetic status of the crypts in the three groups was then analysed and compared. Those in which the mucosae were predominantly or totally convoluted (group 3) showed the most notable cytokinetic changes: crypts were hyperplastic and crypt cell production rate was markedly increased compared with the other two groups and with morphologically normal control mucosae. In the case of one patient with mucosal changes of group 3 severity, additional studies were carried out using vincristine to produce metaphase arrest. The cell cycle time of 27 hours was greatly shortened compared with a control value of 45 hours.We find that the presence of convolutions in small-intestinal mucosal biopsy specimens is accompanied by an increase in the rate of cell production from the crypts, which is presumably related directly or indirectly to the rate of loss of mature enterocytes from the surface of the mucosa. Furthermore, an increase in the proportion of convolutions may reflect an increase in the rates of cell production and cell loss. In the group 3 convoluted mucosae the cytokinetic profile of the crypts resembled that of some of the flat avillous coeliac mucosae previously studied although the rates of cell production did not reach the levels attained by the most productive of the flat coeliac mucosae.

Coeliac disease with farmers' lung

Two patients with allergic alveolitis due to mouldy hay antigens (farmer's lung) were shown to have malabsorption due to coeliac disease. As similar associations have been found with other alveolar diseases, this association is probably not fortuitous and further population screening should be done.

Coeliac disease: a cause of various associated diseases?

Deposition in other organs of immune complexes originating from the small-intestinal musosa is suggested as a possible reason, in some patients, for the described association between coeliac disease and a range of "autoimmune" diseases.

A study of the cellular infiltrate of the proximal jejunal mucosa in ulcerative colitis and Crohn's disease

The cellular infiltrate of the proximal jejunum has been compared between 20 subjects without gastrointestinal disease, 20 subjects with ulcerative colitis, and 26 subjects with Crohn's disease. A significant increase (P smaller than 0.001) in the plasma cell infiltrate was noted in subjects with ulcerative colitis and a more marked increase in subjects with Crohn's disease (P smaller than 0.001). Such increases may be relevant to raised serum IgA levels following panproctocolectomy for ulcerative colitis or recurrence in the small intestine in Crohn's disease.

Coeliac disease and autoimmunity

Among fifty-seven patients with proven coeliac disease three also had thyrotoxicosis, two insulin dependant diabetes, three fibrosing alveolitis and one each had vitiligo, rheumatoid arthritis and cryptogenic cirrhosis. Autoantibodies were demonstrated in twelve of thirty-one patients tested, seven of these twelve had one of the above associated conditions. Antireticulin antibodies were found in seven of twenty-three patients tested, and there was a significant association with dietary gluten. These findings appear to support that coeliac disease is associated with disturbed immunity and that a predisposition to autoimmunity may exist.

Incidence of small-intestinal mucosal abnormalities and of clinical coeliac disease in the relatives of children with coeliac disease

Evidence is presented of a higher than normal incidence both of clinical coeliac disease and of small-intestinal mucosal abnormalities in relatives of children with coeliac disease. In such relatives the incidence of mucosal abnormality may differ from the incidence of clinical coeliac disease. The data show an absence of any simple Mendelian pattern of inheritance: in place of the hypothesis that inheritance is through a dominant gene of reduced penetrance, it is argued that the pathogenesis of coeliac disease is multifactorial, the genetic basis of susceptibility being polygenic and interacting with environmental factors. On this hypothesis the relative contributions of inheritance and environment to liability to the clinical condition are estimated, the genetic component being 45% +/- 9. Environmental factors appear more important in the development of mucosal abnormality.