Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care

The prevalence of celiac disease among patients with nonconstipated irritable bowel syndrome is similar to controls

BACKGROUND & AIMS

Guidelines recommend that patients with symptoms of nonconstipated irritable bowel syndrome (NC-IBS) undergo testing for celiac disease (CD). We evaluated the prevalence of CD antibodies, and biopsy confirmed CD among patients with NC-IBS in a large US population.

METHODS

In a study conducted at 4 sites, from 2003 to 2008, we compared data from 492 patients with symptoms of NC-IBS to 458 asymptomatic individuals who underwent colonoscopy examinations for cancer screening or polyp surveillance (controls). All participants provided blood samples for specific and nonspecific CD-associated antibodies. Additionally, patients with IBS were analyzed for complete blood cell counts, metabolic factors, erythrocyte sedimentation rates, and levels of C-reactive protein and thyroid-stimulating hormone. Any subjects found to have CD-associated antibodies were offered esophagogastroduodenoscopy and duodenal biopsy analysis.

RESULTS

Of patients with NC-IBS, 7.3% had abnormal results for CD-associated antibodies, compared with 4.8% of controls (adjusted odds ratio, 1.49; 95% confidence interval: 0.76-2.90; P=.25). Within the NC-IBS group, 6.51% had antibodies against gliadin, 1.22% against tissue transglutaminase, and 0.61% against endomysium (P>.05 vs controls for all antibodies tested). CD was confirmed in 0.41% of patients in the NC-IBS group and 0.44% of controls (P>.99).

CONCLUSIONS

Although CD-associated antibodies are relatively common, the prevalence of CD among patients with NC-IBS is similar to that among controls in a large US population. These findings challenge recommendations to routinely screen patients with NC-IBS for CD. More than 7% of patients with NC-IBS had CD-associated antibodies, suggesting that gluten sensitivity might mediate IBS symptoms; further studies are needed.

The association of coeliac disease in childhood with functional gastrointestinal disorders: a prospective study in patients fulfilling Rome III criteria

BACKGROUND

An association between coeliac disease (CD) and functional gastrointestinal disorders (FGIDs) has at present only been demonstrated in adults.

AIMS

To assess the prevalence of FGIDs at 1 year and the role of psychological aspects on the development of FGIDs in CD children.

METHODS

One-hundred consecutive CD children (36M and 64F) were followed up for 1 year. Fifty-six children (25M and 31F) represented the control group. All children and/or their parents completed validated questionnaires for GI symptoms, depression, and anxiety. GI symptoms at diagnosis and after 1 year of gluten-free diet (GFD) were compared.

RESULTS

Twenty-three/82 (28%) CD patients followed up prospectively, on GFD from at least 1 year, fulfilled the Rome III criteria for FGIDs compared with 5/56 (8.9%) controls (P = 0.008; χ² = 6.8; OR: 3.97; 95% CI: 1.40-11.21). Children complaining with GI symptoms alone [21/52 (40.3%)] more likely fulfilled Rome III criteria for FGIDs after 1 year of GFD than children with extra-intestinal symptoms (P = 0.045). CD children with FGDIs presented significantly higher anxiety and depression compared to CD children without FGIDs and controls (P = 0.02).

CONCLUSIONS

This study demonstrates that children with CD on a GFD for a year have a much higher prevalence of functional GI symptoms than do controls. Whether the risk is due to the residua of a chronic inflammatory process, and/or due to psychological factors remains to be further tested.

Bile acid malabsorption: an under-investigated differential diagnosis in patients presenting with diarrhea predominant irritable bowel syndrome type symptoms

OBJECTIVE

Bile acid malabsorption (BAM) has been reported as a possible cause of diarrhea predominant irritable bowel syndrome (D-IBS) type symptoms. We aimed to determine how commonly patients with D-IBS type symptoms had a diagnosis of BAM as demonstrated by a positive SeHCAT (75 Selenium-homocholic acid taurine) test (retention <10% at seven days).

MATERIALS AND METHODS

A retrospective analysis was undertaken of patient's records for all patients who underwent a SeHCAT test between 2001 and 2009 in a tertiary hospital (Group A). Concurrently, a cohort of patients with Rome II D-IBS type symptoms was examined to determine the potential utility of SeHCAT test (Group B).

RESULTS

In Group A 39.2% (n = 107/273) of patients had a positive SeHCAT result. The median time from first hospital visit to SeHCAT result was 30 weeks. Predictive factors for BAM: terminal ileal Crohn's disease (p < 0.01), terminal ileal resection (p < 0.01), and previous cholecystectomy (p < 0.01). 33.6% of patients who had a positive SeHCAT also had Rome II D-IBS. In Group B the D-IBS control cohort only 1.9% of patients had undergone a SeHCAT scan (p < 0.001 compared to Group A).

CONCLUSION

BAM is common and should be considered earlier when investigating unselected patients with D-IBS type symptoms.

Screening for celiac disease in a North American population: sequential serology and gastrointestinal symptoms

OBJECTIVES

The prevalence of diagnosed celiac disease is <1 in 2,000 in the United States, but screening studies undertaken in European and other populations have revealed a much higher prevalence. The objective of this study was to determine the prevalence of celiac disease and the utility of screening in the general adult population of a geographically isolated area.

METHODS

Serum tissue transglutaminase antibodies (tTG-IgA) were measured in volunteer health-care participants aged ≥ 18 years at the annual Casper, Wyoming, Blue Envelope Health Fair blood draw. Subjects with positive tTG-IgA tests had their endomysial IgA antibodies checked. Double positives were offered endoscopy with small bowel biopsy. All subjects completed a short gastrointestinal (GI) symptom questionnaire.

RESULTS

A total of 3,850 residents of the Natrona County had serologic evaluation for celiac disease, 34 of whom tested positive for both tTG and endomysial antibody (EMA) IgA. Excluding three individuals with previous diagnosis of celiac disease, the overall prevalence of positive celiac serology in this community sample was 0.8%. All 31 subjects were offered a small bowel biopsy. Of the 18 biopsied subjects, 17 (94%) had at least partial villous atrophy. Symptoms that were reported by the fair attendees did not predict positivity.

CONCLUSIONS

Screening for celiac disease was widely accepted in this preventative health-care setting. Undiagnosed celiac disease affects 1 in 126 individuals in this Wyoming community. Most were asymptomatic or had atypical presentations. Serologic testing can readily detect this disease in a general population.

The role of fecal elastase-1 in detecting exocrine pancreatic disease

Exocrine pancreatic disease is thought to be uncommon in clinical practice and usually secondary to excess alcohol intake. Although excess alcohol intake does account for many cases of exocrine pancreatic disease, other conditions are associated with exocrine pancreatic insufficiency and such dysfunction perhaps occurs more frequently than conventionally expected. A reliable, patient-friendly, cheap and easy to use test for exocrine pancreatic disease is yet to be established; however, in many countries the main (and often only available) method of assessment of exocrine pancreatic function is the fecal-elastase-1 test. This Review examines the role of fecal-elastase-1 testing in detecting exocrine pancreatic insufficiency in a number of gastrointestinal and nongastrointestinal conditions and determines the value of pancreatic enzyme supplementation in these settings.

Impaired uptake of serotonin by platelets from patients with irritable bowel syndrome correlates with duodenal immune activation

BACKGROUND & AIMS

Patients with irritable bowel syndrome with diarrhea (IBS-D) have increased mucosal serotonin (5-hydroxytryptamine [5-HT]) availability, possibly because immune activation reduces activity of the 5-HT transporter (SERT). We investigated the relationship between mucosal and platelet SERT and immune activation of the duodenal mucosa in patients with IBS-D.

METHODS

We quantified mucosal intraepithelial lymphocytes (IELs), mast cells, and enterochromaffin cells in blood samples, measured levels of SERT messenger RNA (mRNA) in mucosal samples, and assessed platelet uptake of 5-HT and platelet membrane binding of (3)H-paroxetine in samples from 29 healthy volunteers (HVs), 20 patients with IBS-D, and 20 untreated patients with celiac disease.

RESULTS

Patients with IBS-D or celiac disease had increased numbers of IELs and mast cells compared with HVs (both P < .001). Levels of SERT mRNA were reduced in the mucosa of patients with IBS-D or celiac disease and were inversely correlated with numbers of IELs (r = -0.72, P < .0001). Uptake of 5-HT by platelets from patients with IBS-D or celiac disease was reduced (mean, 17.1 ± 3.5 and 28.3 ± 4.1 nmol·min(-1)·mg(-1), respectively) compared with HVs (50.8 ± 8.0 nmol·min(-1)·mg(-1), P < .01 and P = .05, respectively). Binding of paroxetine to membranes of platelets from patients with IBS-D (median [interquartile range], 226 [92-405] fmol/mg protein) was significantly greater than that from HVs (109 [69-175] fmol/mg protein) and correlated inversely with platelet uptake of 5-HT (r = -0.62, P = .03). Tryptase release from incubated biopsy samples was significantly increased in patients with IBS-D (2.2 [0.42-3.5] vs 0.50 [0.25-0.86] ng·mL(-1)·mg(-1) for HVs; P = .03).

CONCLUSIONS

Platelet SERT is reduced in IBS-D and associated with reduced levels of SERT mRNA and duodenal immune activation.

Biopsychosocial model of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common chronic disorder seen in gastroenterology and primary care practice. It is characterized by recurrent abdominal pain or discomfort associated with disturbed bowel function. It is a heterogeneous disorder with varying treatments, and in this regard physicians sometimes struggle with finding the optimal approach to management of patients with IBS. This disorder induces high health care costs and variably reduces health-related quality of life. IBS is in the class of functional gastrointestinal disorders, and results from dysregulation of central and enteric nervous system interactions. Psychosocial factors are closely related to their gut physiology, associated cognitions, symptom manifestations and illness behavior. Therefore, it is important for the physician to recognize the psychosocial issues of patients with IBS and in addition to build a good patient-physician relationship in order to optimize treatment. This review focuses on the interaction between psychological and physiological factors associated with IBS by using a biopsychosocial model. In this article, we describe (1) the predisposing psychological features seen in early life; (2) the psychological factors associated with life stress, the symptom presentation, and their associated coping patterns; (3) gut pathophysiology with emphasis on disturbances in motility, visceral hypersensitivity and brain-gut interactions; and finally (4) the clinical outcomes and effective treatments including psychotherapeutic methods.

Biopsychosocial model of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common chronic disorder seen in gastroenterology and primary care practice. It is characterized by recurrent abdominal pain or discomfort associated with disturbed bowel function. It is a heterogeneous disorder with varying treatments, and in this regard physicians sometimes struggle with finding the optimal approach to management of patients with IBS. This disorder induces high health care costs and variably reduces health-related quality of life. IBS is in the class of functional gastrointestinal disorders, and results from dysregulation of central and enteric nervous system interactions. Psychosocial factors are closely related to their gut physiology, associated cognitions, symptom manifestations and illness behavior. Therefore, it is important for the physician to recognize the psychosocial issues of patients with IBS and in addition to build a good patient-physician relationship in order to optimize treatment. This review focuses on the interaction between psychological and physiological factors associated with IBS by using a biopsychosocial model. In this article, we describe (1) the predisposing psychological features seen in early life; (2) the psychological factors associated with life stress, the symptom presentation, and their associated coping patterns; (3) gut pathophysiology with emphasis on disturbances in motility, visceral hypersensitivity and brain-gut interactions; and finally (4) the clinical outcomes and effective treatments including psychotherapeutic methods.

Existing and emerging therapies for irritable bowel syndrome

INTRODUCTION

Irritable bowel syndrome is a common disorder that is associated with a significant impact on both affected individuals and society. While the pathophysiology of irritable bowel syndrome remains unknown, knowledge regarding the normal and abnormal functions of the gut and its complex interaction with the body's nervous systems continues to shed light on the multifactorial origins of irritable bowel syndrome symptoms. This article provides an overview of the current knowledge of the therapeutic approaches to irritable bowel syndrome.

AREAS COVERED

A search of the online bibliographic databases MEDLINE and EMBASE was performed in order to identify all relevant articles published between 1980 and 2010. The search was enhanced with the use of a medical librarian. Bibliographies from potentially relevant articles were manually searched.

EXPERT OPINION

The therapeutic options for irritable bowel syndrome are rapidly evolving beyond traditional symptom-based therapies, such as fiber, antispasmodics, antidiarrheals and laxatives, and are moving toward agents with organ-specific receptor selectivity directed, in many cases, at specific gastrointestinal functions.

Celiac disease: diagnostic criteria in progress

Until a few years ago, celiac disease (CD) was thought to be a rare food intolerance that was confined to childhood and characterized by severe malabsorption and flat intestinal mucosa. Currently, CD is regarded as an autoimmune disorder that is common in the general population (affecting 1 in 100 individuals), with possible onset at any age and with many possible presentations. The identification of CD is challenging because it can begin not only with diarrhea and weight loss but also with atypical gastrointestinal (constipation and recurrent abdominal pain) and extra-intestinal symptoms (anemia, raised transaminases, osteoporosis, recurrent miscarriages, aphthous stomatitis and associated autoimmune disorders), or it could be completely symptomless. Over the last 20 years, the diagnostic accuracy of serology for CD has progressively increased with the development of highly reliable tests, such as the detection of IgA tissue transglutaminase and antiendomysial and IgG antideamidated gliadin peptide antibodies. The routine use of antibody markers has allowed researchers to discover a very high number of 'borderline' cases, characterized by positive serology and mild intestinal lesions or normal small intestine architecture, which can be classified as potential CD. Therefore, it is evident that the 'old celiac disease' with flat mucosa is only a part of the spectrum of CD. It is possible that serology could identify CD in its early stages, before the appearance of severe intestinal damage. In cases with a positive serology but with mild or absent intestinal lesions, the detection of HLA-DQ2 and HLA-DQ8 can help reinforce or exclude the diagnosis of gluten sensitivity.

Risk of tuberculosis in a large sample of patients with coeliac disease--a nationwide cohort study

BACKGROUND

Research suggests a positive association between coeliac disease and tuberculosis (TB), but that research has often been limited to in-patients and small sample size. We examined the relationship between TB and coeliac disease.

AIM

To examine the association of TB and coeliac disease.

METHODS

We collected biopsy data from all pathology departments in Sweden (n=28) to identify individuals who were diagnosed with coeliac disease between 1969 and 2007 (Marsh 3: villous atrophy; n=29,026 unique individuals). Population-based sex- and age-matched controls were selected from the Total Population Register. Using Cox regression, we calculated hazard ratios (HRs) for TB from data in the Swedish national health registers.

RESULTS

Individuals with coeliac disease were at increased risk of TB (HR=2.0; 95% CI=1.3-3.0) (during follow-up, 31 individuals with coeliac disease and 74 reference individuals had a diagnosis of TB). The absolute risk of TB in patients with coeliac disease was 10/100,000 person-years with an excess risk of 5/100,000. Risk estimates were the highest in the first year. Restricting our outcome to a diagnosis of TB confirmed by (I) a record of TB medication (HR=2.9; 95% CI=1.0-8.3), (II) data in the National Surveillance System for Infectious Diseases in Sweden (HR=2.6; 95% CI=1.3-5.2) or (III) positive TB cultivation (HR=3.3; 95% CI=1.6-6.8) increased risk estimates. The positive association between coeliac disease and TB was also observed before the coeliac disease diagnosis (odds ratio=1.6; 95% CI=1.2-2.1).

CONCLUSION

We found a moderately increased risk of tuberculosis in patients with coeliac disease.

The role of diagnostic testing in irritable bowel syndrome

This article discusses the diagnostic criteria and processes applicable to irritable bowel syndrome (IBS). The authors describe the various diagnostic criteria with a focus on the Rome criteria for IBS and the judicious application of historical information such as alarm features and the yield of various diagnostic modalities such as blood, stool, breath, and endoscopic tests.

Anorectal function and visceral hypersensitivity in celiac disease

OBJECTIVE

To evaluate anorectal function and rectal sensitivity thresholds in patients with celiac disease (CD).

METHODS

In 25 unselected patients with CD (16 female, 9 male; mean age 45, range 24 to 75 y) and 20 controls (12 female, 8 male; mean age 41, range 20 to 65 y) anorectal manometry and rectal balloon distension test were conducted using a 4 lumen water perfused catheter with a polyethylene balloon (Zinectics Manometric Catheter, Medtronic).

RESULTS

In celiac patients the maximal anal resting pressure, reflecting the internal anal sphincter function, was significantly higher than that in the controls: 87.8±21.7 mm Hg versus 66.7±15.2 mm Hg (P<0.001). There were no considerable differences between both the groups neither in the maximal anal squeeze nor in the cough pressures. Celiac patients had significantly lower first sensation threshold: 25.6±10.8 mL versus 37.5±12.5 mL (P<0.05). Visceral hypersensitivity (rectal pain/discomfort threshold ≤100 mL) was observed in 36% of celiac patients and in none of the controls (P<0.01).

CONCLUSIONS

The increased anal resting pressure and rectal hypersensitivity are observed in CD. Disturbances in gastrointestinal motility and visceral perception in the course of CD may occur at different levels of the brain-gut axis including direct changes in the enteric nervous system.

The prevalence of celiac disease in patients fulfilling Rome III criteria for irritable bowel syndrome

BACKGROUND AND AIMS

Celiac disease shares several symptoms which constitute some of the ROME criteria used for the diagnosis of irritable bowel syndrome (IBS), and as such many patients with underlying Celiac disease may be mistakenly diagnosed as having IBS. The aim of the present study was to determine the prevalence of Celiac disease in patients with IBS fulfilling ROME III criteria.

MATERIALS AND METHODS

Patients who fulfilled ROME III criteria for irritable bowel syndrome were screened for Celiac disease using the Biocard(TM) Celiac Disease Stick test, and patients who tested positive had their serum samples analyzed for antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies. Patients with detectable antibody levels underwent endoscopic duodenal biopsy to confirm a diagnosis of Celiac disease.

RESULTS

Two of 100 patients who were diagnosed as having irritable bowel syndrome as per the Roma III criteria were found to have elevated levels of serum antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies, with histological evidence of Celiac disease on examination of duodenal biopsy. Both patients were started on a gluten-free diet, showing significant improvement in their symptoms on follow-up.

CONCLUSIONS

Celiac disease is a common finding among patients labeled as IBS. Celiac disease must be considered in differential diagnosis of IBS especially in the therapy refractory group.

Irritable bowel syndrome: can nutrient manipulation help?

PURPOSE OF REVIEW

To describe the evidences for the usefulness of dietary manipulations (including the use of probiotics and prebiotics) in the management of irritable bowel syndrome (IBS).

RECENT FINDINGS

Exclusion diets do not have a role in the management of these patients except in the case of malabsorbed sugars (lactose, fructose). However, recent work suggests that excluding these sugars is more effective in non-IBS than in IBS patients. Also, the first small open series on the use of very low (20 g/day) carbohydrate diet (VLCD) in IBS has been published with promising results. However, safety concerns do not allow us to recommend them. In the period of review, further evidence has been provided on the role of psyllium in IBS. Also, the available evidence on the use of probiotics in IBS has been meta-analyzed.

SUMMARY

IBS patients should eat a balanced diet without restrictions, and (except for malabsorbed sugars) exclusion diets are not useful in most of them. The role of VLCD remains to be established. The concept that increasing fiber intake is useful for IBS may not be true for all patients, and hydrophilic colloids (e.g. psyllium) are preferred. There is growing evidence for the effectiveness of probiotics in IBS.

Diagnostic immunology in celiac disease

Serum autoantibodies to transglutaminase and endomysium are found in the majority of patients with celiac disease, an autoimmune multisystem disorder affecting approximately 1% of Western and Middle-Eastern populations. Detection of these antibodies plays a crucial role in the diagnosis of celiac disease. The aim of this review is to summarize recent publications in this field, with particular focus on the applications and limitations of celiac autoantibody testing in routine clinical practice.

Some patients with irritable bowel syndrome may have exocrine pancreatic insufficiency

BACKGROUND & AIMS

Patients with irritable bowel syndrome (IBS) might have other underlying pathologies. Pancreatic disease can be elusive-especially in the early stages, and some symptoms overlap with those of IBS. We evaluated the prevalence of exocrine pancreatic insufficiency in diarrhea-predominant IBS (D-IBS) and assessed the effects of pancreatic enzyme supplementation.

METHODS

The study included patients who met the Rome II criteria for D-IBS, patients with chronic diarrhea, and subjects without diarrhea (controls). Subjects' baseline weight, stool frequency, stool consistency (using the Bristol score), and fecal elastase-1 (Fel-1) levels were determined. Patients were assessed using British Society of Gastroenterology IBS guidelines. Patients with Fel-1 levels less than 100 microg/g stool (indicating pancreatic exocrine insufficiency; group 1) were compared with age- and sex-matched patients with D-IBS and normal levels of Fel-1 (group 2), given pancreatic enzyme therapy, and reassessed at 12 weeks.

RESULTS

Fel-1 levels were less than 100 microg/g in stool from 19 of 314 patients with D-IBS (6.1%; 95% confidence interval [CI], 3.7%-9.3%), none of the 105 patients with chronic diarrhea (95% CI, 0.0%-3.5%), and none of 95 controls (95% CI, 0.0-3.8%) (P < .001). After enzyme supplementation, improvements in stool frequency (P < .001), stool consistency (P < .001), and abdominal pain (P = .003) were observed in patients in group 1, but not in group 2.

CONCLUSIONS

Pancreatic exocrine insufficiency was detected in 6.1% of patients who fulfilled the Rome II criteria for D-IBS. In these patients, pancreatic enzyme therapy might reduce diarrhea and abdominal pain. Pancreatic exocrine insufficiency should be considered in patients with D-IBS.

[Diagnosis of irritable bowel syndrome]

The diagnosis of irritable bowel syndrome (IBS) is a clinical diagnosis, based on the Rome III criteria. The identification of alarm features (red flags), associated with an organic digestive pathology is a key point during the initial screening. Age over 50 years, blood in feces, and diarrhea seem to be the three most specific red flags. Biological and morphological examinations must be performed cautiously; their profitability is low in patients with Rome criteria. In the majority of clinical situations encountered in daily clinical practice, a positive diagnosis of IBS can be made.

Celiac disease in patients with presumed irritable bowel syndrome: A case-finding study

AIM: To estimate the prevalence of celiac disease (CD) in adult patients with presumed irritable bowel syndrome (IBS).

METHODS: Between March 2005 and December 2008, 742 consecutive patients (293 male, median age 43 years, range 18-69 years) fulfilling the Rome II criteria for IBS were prospectively enrolled in the study. IBS was diagnosed via self-completed Rome II modular questionnaires. Anti-tissue transglutaminase (anti-tTG) serology was checked to initially recognize possible CD cases. Patients with a positive test were offered endoscopic duodenal biopsy to confirm the diagnosis of CD.

RESULTS: Thirty two patients (15 male, median age 41 years, range 19-59 years) were found to have organic diseases other than CD. Twenty four patients tested positive for anti-tTG antibodies, and duodenal biopsies confirmed the diagnosis in all of them. Thus, in this patient population with presumed IBS, 3.23% actually had CD.

CONCLUSION: CD is common in patients with presumed IBS. Routine screening for CD in patients with symptoms of IBS is recommended.

Irritable bowel syndrome: role of food in pathogenesis and management

Patients with the irritable bowel syndrome (IBS) commonly report the precipitation of symptoms on food ingestion. Though the role of dietary constituents in IBS has not been extensively studied, food could contribute to symptom onset or even the causation of IBS through a number of mechanisms. First, the physiological response of the intestine to food ingestion could precipitate symptoms in predisposed individuals; second, there is some evidence that allergy or intolerance to a particular food can produce IBS-like symptoms, third, certain foods may alter the composition of the luminal milieu, either directly or indirectly through effects on bacterial metabolism, and thus induce symptoms and, finally, IBS may develop following exposure to food-borne pathogens. Anticipatory, psychological factors generated by previous negative experiences with food ingestion or other factors may also contribute though their contribution has been scarcely quantified. Not surprisingly, there is considerable interest in the potential roles of diet and food supplements in the therapy of IBS; for the most part, the evidence base for such recommendations remains slim though certain probiotics show considerable promise.

Between celiac disease and irritable bowel syndrome: the "no man's land" of gluten sensitivity

The repertoire of gastrointestinal (GI) symptoms is finite; however, the etiologies and mechanisms underlying symptom generation and perception are diverse and, in many cases, unknown. This review examines the clinical and experimental evidence exploring the putative relationship between gluten sensitivity (GS) and the generation of GI symptoms. It explores the hypothesis that, in a proportion of patients, GS causes functional bowel disorder (FBD)-like symptoms. We propose a model for investigating and understanding the induction of GI symptoms and dysfunction by gluten in FBD and organic disease. We hypothesize that, even in the absence of fully developed celiac disease, gluten can induce symptoms similar to FBD. We discuss the hypothesis that GS and post-infectious irritable bowel syndrome (IBS) provide two triggers that can explain at least part of the spectrum that constitutes IBS, further advancing an understanding of the role of mucosal responses to luminal factors in FBDs. We propose that the animal model of GS in human leukocyte antigen (HLA)- DQ8 mice allows investigation of mucosal pathophysiological changes that occur before the onset of full-blown inflammation in a GS host. A better understanding of how gluten can cause symptoms in sensitive individuals will illuminate the interaction between host genotype, diet, and intestinal microbiota in generating one of the most common GI conditions.

Review article: Small intestinal bacterial overgrowth, bile acid malabsorption and gluten intolerance as possible causes of chronic watery diarrhoea

BACKGROUND

Chronic watery diarrhoea is one of the most common symptoms prompting GI evaluation. Recently, new diagnostic considerations have emerged as possible factors in chronic diarrhoea.

AIM

To review available data regarding diagnosis and treatment of chronic diarrhoea with an emphasis on bacterial overgrowth and bile acid malabsorption.

METHODS

A systematic search of the English language literature of chronic diarrhoea was performed focused on three possible aetiologies of diarrhoea: small intestinal bacterial overgrowth (SIBO), idiopathic bile salt malabsorption (IBAM), gluten responsive enteropathy.

RESULTS

Recent studies suggest that SIBO and bile acid malabsorption may have been underestimated as possible causes of chronic watery diarrhoea. Gluten intolerance with negative coeliac serology is a contentious possible cause of watery diarrhoea, but requires further research before acceptance as an entity.

CONCLUSION

In patients with otherwise unexplained chronic watery diarrhoea, small intestinal bacterial overgrowth and bile salt malabsorption should be considered and investigated.

Postinfectious irritable bowel syndrome

Approximately 1 in ten patients with irritable bowel syndrome (IBS) believe their IBS began with an infectious illness. Prospective studies have shown that 3% to 36% of enteric infections lead to persistent new IBS symptoms; the precise incidence depends on the infecting organism. Whereas viral gastroenteritis seems to have only short-term effects, bacterial enteritis and protozoan and helminth infections are followed by prolonged postinfective IBS (PI-IBS). Risk factors for developing PI-IBS include, in order of importance, prolonged duration of initial illness, toxicity of infecting bacterial strain, smoking, mucosal markers of inflammation, female gender, depression, hypochondriasis, and adverse life events in the preceding 3 months. Age older than 60 years might protect against PI-IBS, whereas treatment with antibiotics has been associated with increased risk. The mechanisms that cause PI-IBS are unknown but could include residual inflammation or persistent changes in mucosal immunocytes, enterochromaffin and mast cells, enteric nerves, and the gastrointestinal microbiota. Adverse psychological factors contribute to persistent low-grade inflammation. The prognosis for patients with PI-IBS is somewhat better than for those with unselected IBS, but PI-IBS can still take years to resolve. There are no specific treatments for PI-IBS; these should be tailored to the predominant bowel disturbance, which is most frequently diarrhea.

Use of serum biomarkers in a diagnostic test for irritable bowel syndrome

BACKGROUND

Currently, no single serum biomarker can reliably differentiate irritable bowel syndrome (IBS) from other functional gastrointestinal disorders or organic diseases of the gastrointestinal tract.

AIM

To develop and validate a diagnostic test using serum biomarkers to detect IBS.

METHODS

Ten serum biomarkers were selected from a potential panel of 140 for their ability to differentiate IBS from non-IBS disease in blood samples from patients with IBS, other gastrointestinal disorders and healthy volunteers. A predictive modelling tool was developed to assess patterns and relationships among the 10 serum biomarkers that best differentiated IBS patients from healthy controls and patients with non-IBS gastrointestinal disease. This model was tested in a different cohort of patients and healthy controls (n = 516) to determine the predictive accuracy of differentiating IBS from non-IBS.

RESULTS

The sensitivity and specificity of the 10-biomarker algorithm for differentiating IBS from non-IBS was 50% and 88% respectively. The positive predictive value was 81%, and the negative predictive value was 64% at 50% IBS prevalence in the validation cohort. Overall accuracy was 70%.

CONCLUSIONS

Assessing serum biomarker patterns can differentiate IBS from non-IBS with reasonable sensitivity and specificity. Assessing serum biomarkers in an overall diagnostic strategy may allow earlier diagnosis and treatment for patients with IBS.

Long-term health and quality-of-life consequences of mass screening for childhood celiac disease: a 10-year follow-up study

OBJECTIVE

Mass screening for celiac disease is controversial. The objective of this study was to determine whether detection of childhood celiac disease by mass screening improves long-term health status and health-related quality of life.

METHODS

We conducted a prospective 10-year follow-up study of 32 children who were aged 2 to 4 years, had celiac disease identified by mass screening, and had a gluten-free diet (19) or a normal gluten-containing diet (13). The follow-up included assessments of general health status, celiac disease-associated symptoms, celiac disease-associated serum antibodies, and health-related quality of life.

RESULTS

Ten years after mass screening, 81% of the children were adhering to a gluten-free diet. The health status improved in 66% of the treated children: in 41% by early treatment and in 25% by prevention of the gluten-dependent symptoms that they developed after diagnosis. For 19% of the children, treatment after screening would not have improved their health status, because they had no symptoms at screening and have remained symptom-free while consuming gluten. The health-related quality of life of the children with symptoms improved significantly after 1 year of gluten-free diet. Ten years after screening, the health-related quality of life of the children with celiac disease was similar to that of the reference population.

CONCLUSION

Identification by mass screening led 10 years later to health improvement in 66% of children without deterioration of generic health-related quality of life. There is a good compliance after mass screening. In a research setting, delaying treatment for children without symptoms seems to be an option after a positive screening test. Long-term follow-up studies are needed to assess possible long-term complications in untreated, nonsymptomatic celiac disease.

Missing celiac disease in family medicine: the importance of hypothesis generation

PURPOSE

Delays in diagnosing celiac disease average 13 years. We aimed to identify reasons for misdiagnosis in family medicine.

BACKGROUND

During a larger study on diagnosis, a scenario describing a 30-year-old female with 3-month abdominal pain, diarrhea, and microcytic anemia consistent with celiac disease was presented on a computer to 84 family physicians. Their information gathering and diagnoses were recorded. Fifty physicians misdiagnosed, and 38 of these took part in "stimulated recall'': they were asked to recall their hypotheses and inferences step by step, aided by a record of their information gathering. They were unaware of the misdiagnosis.

ANALYSES

Transcripts were analyzed to identify whether celiac disease was mentioned and how information was interpreted. Two raters independently assessed information interpretation against the published evidence (kappa = 0.85).

RESULTS

Physicians did not change their diagnoses during stimulated recall. Only 10 physicians mentioned celiac disease as a hypothesis (26%). "Diarrhea'' and "pain relief by defecation,'' consistent with both celiac disease and irritable bowel syndrome (IBS), were only linked to IBS. "Absence of weight loss'' led to rejecting celiac disease, although weight loss is characteristic of advanced disease. A complete blood count was requested as a routine test and not specifically for celiac disease. Thus, the unexpected result of "microcytic anemia,'' inconsistent with IBS, did not trigger the correct diagnosis.

CONCLUSIONS

Most physicians never considered celiac disease. Information inconsistent with the favorite IBS diagnosis was overlooked. Reviewing the case did not prompt physicians to consider celiac disease, re-evaluate the evidence, or rethink the IBS diagnosis.

Efficient diagnosis of suspected functional bowel disorders

Functional bowel disorders (FBDs) are common disorders that are characterized by various combinations of abdominal pain and/or discomfort, bloating and changes in bowel habits. At present, diagnosing FBDs often incurs considerable health-care costs, partly because unnecessary investigations are performed. Patients are currently diagnosed as having an FBD on the basis of a combination of typical symptoms, normal physical examination and the absence of alarm features indicative of an organic gastrointestinal disease. Basic laboratory investigations, such as a complete blood count, measurement of the erythrocyte sedimentation rate and serological tests for celiac disease, are useful in the initial evaluation. No further investigations are needed for most patients who have typical symptoms and no alarm symptoms. The most important alarm symptoms include signs of gastrointestinal bleeding, symptom onset above 50 years of age, a family history of colorectal cancer, documented weight loss and nocturnal symptoms. The presence of alarm symptoms obviously does not exclude an FBD, but further investigation is needed before confirmation of the diagnosis. For patients with predominant and severe diarrhea, a more thorough diagnostic work-up should normally be considered, including colonoscopy with colonic biopsies and a test for bile-acid malabsorption.

Predictors of family risk for celiac disease: a population-based study

BACKGROUND & AIMS

There is an elevated prevalence of celiac disease (CD) in family members (FMs) of CD patients, but most prior studies have been done on selected populations. Our aim was to determine the clinical, serologic, and genetic predictors of CD in FMs of a population-based cohort of index cases.

METHODS

Index cases from southeast Minnesota provided contact information for their first-degree relatives. FMs were examined for endomysial antibodies (EMAs), tissue transglutaminase antibodies (tTGAs), and HLA-DQ genotyping. Two questionnaires were applied, Bowel Disease Questionnaire and Short Form Health Survey. Intestinal biopsies were offered if there were any positive autoantibody or seronegative FMs with gastrointestinal symptoms and HLA-DQ at risk for CD.

RESULTS

We recruited 111 index cases that had 579 FMs, of whom 344 (59%) were investigated. The average screening rate among families was 65%. A positive tTGA test was found in 47 (14%), 33 with a positive EMA test. CD was diagnosed in 39 (21 males), with an estimated prevalence of 11% (lambda(R) = 16.1). All affected FMs carried the at-risk genotypes. Twenty-one (54%) had "silent" disease, most with severe intestinal villous atrophy. Carrying HLA-DQ2 (odds ratio, 16.1; 95% confidence interval, 2.1-123) and being a sibling (odds ratio, 2.5; 95% confidence interval, 1.1-5.8) are high-risk factors for CD.

CONCLUSIONS

CD is more common in first-degree relatives than previously reported in the United States, with siblings having the greatest risk. There is male preponderance of new cases, and many had silent disease despite severe histologic injury. A more proactive case-finding strategy in FMs might improve the diagnostic rate of CD in North America.

Age-related clinical, serological, and histopathological features of celiac disease

BACKGROUND

Celiac disease (CD) is a common disorder in children and adults. However, limited data are available when comparing differences between both populations.

AIMS

To prospectively evaluate and compare the clinical and histological features present at diagnosis in a cohort of celiac children and adults.

METHODS

Consecutive new cases diagnosed between 2000 and 2006 were prospectively included (66 children and 54 adults). The clinical spectrum was categorized in two groups: (a) typical (malabsorption, chronic diarrhea, or failure to thrive) and (b) oligosymptomatic (abdominal pain, anemia, hypertransaminasemia, or screening in risk groups or in relatives). The histological results were divided into mild (i.e., Marsh I, II, and IIIA) and severe (i.e., Marsh IIIB, IIIC). In all cases, the human antitissue transglutaminase IgA antibodies (TTGA) were determined.

RESULTS

Overall, a female/male ratio (2.6:1) was observed. This ratio was significantly higher in adults (5.7:1) than in children (1.6:1) (P= 0.009). Typical symptoms were present in 62.5% children versus 31% adults (P= 0.01). The average time to diagnosis after the appearance of symptoms was 7.6 months for children and 90 months for adults (P < 0.001). TTGA levels were higher in children and correlated with age (P < 0.001) and with the degree of villous atrophy (P < 0.001). Histological analysis revealed a marked atrophy in 86% children versus 52% adults (P < 0.001). The degree of villous atrophy was inversely correlated with age (P < 0.001). Classic symptoms were also associated with more severe villous atrophy.

CONCLUSIONS

At initial diagnosis, CD shows age-related differences, which consist of more evident clinical and histological features in children. Furthermore, IgA TTGA levels correlate both with the degree of villous atrophy and with the patient's age.

Serotonin and GI clinical disorders

Serotonin is widely distributed throughout the gut within both the enteric nerves and enterochromaffin (EC) cells. EC cells are located in the gut mucosa with maximal numbers in the duodenum and rectum where they act as signal transducers, responding to pressure and luminal substances both bacterial and dietary. Activation leads to serotonin release which acts on a range of receptors on mucosal afferent and myenteric interneurones to initiate secretomotor reflexes. These cause nausea and vomiting as well as intestinal secretion, propulsion and if pronounced, diarrhoea. Inflammation in animal models acts via T lymphocytes to increase EC cell numbers and mucosal serotonin (5-HT) content while inflammatory cytokines decrease serotonin transporter (SERT) function. Inflammation due to coeliac disease and following gastrointestinal infection increases mucosal 5-HT availability by a combination of increased EC cells and depressed SERT. Irritable bowel syndrome (IBS) developing after gastrointestinal infection and IBS with diarrhoea is associated with excess 5-HT. The associated diarrhoeal symptoms respond well to 5-HT(3) receptor antagonists. These drugs also inhibit the nausea and vomiting occurring in patients undergoing chemotherapy which cause a marked increase in release of 5-HT as well as other mediators. Other conditions including IBS-C and constipation may have inadequate 5-HT release and benefit from both 5-HT(3) and 5-HT(4) receptor agonists.

Association of gluten enteropathy and irritable bowel syndrome in adult Turkish population

PURPOSE

Irritable bowel syndrome is generally diagnosed according to the symptoms of the patient, and gluten enteropathy can also be presented with similar symptoms (diarrhea and/or constipation) of irritable bowel syndrome. Aimed to assess the association and the frequency of gluten enteropathy in a group of Turkish patients diagnosed as irritable bowel syndrome.

RESULTS

Found anti-gliadin IgA positivity only in four patients among patients with irritable bowel syndrome. However, none of these four patients had anti-endomycium positivity or any histopathological findings specific for gluten enteropathy. All these four patients had normal histology in their small bowel biopsies.

CONCLUSION

Irritable bowel syndrome is a common problem in the population, but gluten enteropathy is not associated with the vast majority of subjects with irritable bowel syndrome as expected. The need for screening gluten enteropathy among these patients is still unclear, and screening with serology only without small bowel biopsy may lead to false positive results.

Coeliac disease

INTRODUCTION

Coeliac disease is a common but often under diagnosed condition with important complications. It is due to immune-mediated gluten intolerance and may present in a number of ways. It has become more frequently diagnosed due to the recognition of the atypical presentations. In recent years, more sensitive and specific serological markers have been developed but the gold standard of diagnosis remains duodenal biopsy. Compliance with a strict, lifelong gluten-free diet is the cornerstone of management, improving symptoms and reducing complications of the disease.

SOURCES OF DATA

For this review, we focused on papers published on coeliac disease in recent years. Particular emphasis was given to clinical papers examining new methods for the diagnosis of coeliac disease or newer therapies for managing complications. The main source was PubMed and the major gastroenterology journals.

AREAS OF AGREEMENT

Coeliac disease is more common than once thought with a prevalence of around 1%. Diagnosis should always be confirmed with a duodenal biopsy. Management of coeliac disease with a gluten-free diet remains the cornerstone of treatment.

AREAS OF CONTROVERSY

Some complications of coeliac disease, especially neurological, are not widely accepted despite growing support from the literature. Management of enteropathy-associated lymphoma has been difficult, and the optimal therapy is not known.

GROWING POINTS

Current understanding is such that coeliac disease is the most widely understood autoimmune condition. 'Atypical' presentations are becoming the most common presenting features of coeliac disease.

AREAS TIMELY FOR DEVELOPING RESEARCH

Alternatives to the gluten-free diet are about to go into clinical studies. Similarly, better serological screening tests may obviate the need for duodenal biopsy. This review will try to summarize the current understanding of coeliac disease with regard to diagnosis, management, complications and future perspectives.

A tale of two cities: typical celiac sprue presenting symptoms are significantly more common in Turkish than in US Patients

GOAL

Recent studies suggest an increasing prevalence of atypical initial symptoms in patients with celiac disease (CD). The aim of this study was to compare the presenting symptoms of CD at 2 comparable referral institutions in South Florida, and in Ankara, Turkey. We retrospectively reviewed the records of patients with an initial diagnosis of CD by small bowel biopsy during the same (1991 to 2001) 10-year period at Cleveland Clinic Florida and University of Ankara, Turkey. A numerical score was assigned to presenting symptom and signs.

RESULTS

There were 28 patients in the South Florida group (51% men) and 40 patients in the Turkish group (35% men) (P=NS). The Turkish patients were significantly younger at diagnosis (36+/-2 y vs. US patients 66+/-3 y) (P<0.0001). Typical celiac symptom scores were similar (Turkey 1.1+/-0.2 vs. South Florida 1.3+/-0.3) (P=NS). Atypical symptom scores were significantly higher in the US patients (1.9+/-0.2) versus those from Turkey (1.2+/-0.1) (P<0.01). The Turkish patients were significantly more likely (P<0.01) to present with chronic diarrhea, hypoalbuminemia, and mactocytosis at the time of diagnosis.

CONCLUSIONS

Although retrospective, this study points to striking differences in the clinical presentation of CD in individuals in South Florida, United States, and Ankara, Turkey, diagnosed during the same time period at both institutions. Turkish patients were younger, and more likely to present with chronic diarrhea, hypoalbuminemia, and microcytosis-as was more commonly seen in the United States in the 1960s and 70s. These findings raise the question of an interplay of demographics with diet and genetics in the presenting symptoms of CD in these 2 distant geographic areas.

Effect of gluten-free diet and co-morbidity of irritable bowel syndrome-type symptoms on health-related quality of life in adult coeliac patients

BACKGROUND

Both coeliac disease and irritable bowel syndrome show impaired health-related quality of life, however, the impact of irritable bowel syndrome-type symptoms on health-related quality of life in coeliac disease is unclear.

AIM

To evaluate the effect of gluten-free diet adherence and irritable bowel syndrome-type symptoms co-morbidity on health-related quality of life in adult coeliac disease patients.

PATIENTS AND METHODS

A total of 1130 adults were enrolled in the study comprising 1001 controls from the general population and 129 diagnosed coeliac disease patients from the University Clinic in Cagliari. Irritable bowel syndrome-type symptoms and health-related quality of life were assessed using the Rome II and the SF-36 questionnaires, respectively.

RESULTS

Irritable bowel syndrome-type symptoms prevalence in controls was 10.1% (102/1001) and 55% (71/129) in the coeliac disease patients. Irritable bowel syndrome-type symptom controls and coeliac disease patients both presented significantly lower health-related quality of life (p<or=0.05) compared to healthy controls. Strict diet coeliac disease patients, compared to partial diet patients, showed significantly (p<or=0.05) better scores in all domains, except physical functioning, physical-role and bodily pain. The lowest scores were found in partial diet coeliac disease patients with irritable bowel syndrome-type symptoms.

CONCLUSIONS

The present results confirm the burden of irritable bowel syndrome-type symptoms and coeliac disease on health-related quality of life. Moreover, these data show that health-related quality of life in coeliac disease is impaired by poor compliance and by co-morbidity with irritable bowel syndrome-type symptoms.

Irritable bowel syndrome and bloating

Gaseous symptoms in irritable bowel syndrome (IBS) including eructation, flatulence, and bloating occur as a consequence of excess gas production, altered gas transit, abnormal perception of normal amounts of gas within the gastrointestinal tract, or dysfunctional somatic muscle activity in the abdominal wall. Because of the prominence of gaseous complaints in IBS, recent investigations have focussed on new insights into pathogenesis and novel therapies of bloating. The evaluation of the IBS patient with unexplained gas and bloating relies on careful exclusion of organic disease with further characterisation of the underlying condition with directed functional testing. Treatment of gaseous symptomatology in IBS should be targeted to pathophysiologic defects whenever possible. Available therapies include lifestyle alterations, dietary modifications, enzyme preparations, adsorbents and agents which reduce surface tension, treatments that alter gut flora, and drugs that modulate gut transit.