Gabriele Riegler

Divergence of gut permeability and mucosal immune gene expression in two gluten-associated conditions: celiac disease and gluten sensitivity

BackgroundCeliac disease (CD) is an autoimmune enteropathy triggered by the ingestion of gluten. Gluten-sensitive individuals (GS) cannot tolerate gluten and may develop gastrointestinal symptoms similar to those in CD, but the overall clinical picture is generally less severe and is not accompanied by the concurrence of tissue transglutaminase autoantibodies or autoimmune comorbidities. By studying and comparing mucosal expression of genes associated with intestinal barrier function, as well as innate and adaptive immunity in CD compared with GS, we sought to better understand the similarities and differences between these two gluten-associated disorders.MethodsCD, GS and healthy, gluten-tolerant individuals were enrolled in this study. Intestinal permeability was evaluated using a lactulose and mannitol probe, and mucosal biopsy specimens were collected to study the expression of genes involved in barrier function and immunity.ResultsUnlike CD, GS is not associated with increased intestinal permeability. In fact, this was significantly reduced in GS compared with controls (P = 0.0308), paralleled by significantly increased expression of claudin (CLDN) 4 (P = 0.0286). Relative to controls, adaptive immunity markers interleukin (IL)-6 (P = 0.0124) and IL-21 (P = 0.0572) were expressed at higher levels in CD but not in GS, while expression of the innate immunity marker Toll-like receptor (TLR) 2 was increased in GS but not in CD (P = 0.0295). Finally, expression of the T-regulatory cell marker FOXP3 was significantly reduced in GS relative to controls (P = 0.0325) and CD patients (P = 0.0293).ConclusionsThis study shows that the two gluten-associated disorders, CD and GS, are different clinical entities, and it contributes to the characterization of GS as a condition associated with prevalent gluten-induced activation of innate, rather than adaptive, immune responses in the absence of detectable changes in mucosal barrier function.

Zonulin Upregulation Is Associated With Increased Gut Permeability in Subjects With Type 1 Diabetes and Their Relatives

Zonulin, a protein that modulates intestinal permeability, is upregulated in several autoimmune diseases and is involved in the pathogenesis of autoimmune diabetes in the BB/Wor animal model of the disease. To verify the association between serum zonulin levels and in vivo intestinal permeability in patients with type 1 diabetes, both parameters were investigated in different stages of the autoimmune process. Forty-two percent (141 of 339) of the patients had abnormal serum zonulin levels, as compared with age-matched control subjects. The increased zonulin levels correlated with increased intestinal permeability in vivo and changes in claudin-1, claudin-2, and myosin IXB genes expression, while no changes were detected in ZO1 and occludin genes expression. When tested in serum samples collected during the pre–type 1 diabetes phase, elevated serum zonulin was detected in 70% of subjects and preceded by 3.5 ± 0.9 years the onset of the disease in those patients who went on to develop type 1 diabetes. Combined, these results suggest that zonulin upregulation is associated with increased intestinal permeability in a subgroup of type 1 diabetic patients. Zonulin upregulation seems to precede the onset of the disease, providing a possible link between increased intestinal permeability, environmental exposure to non–self antigens, and the development of autoimmunity in genetically susceptible individuals.

Alterations of the intestinal barrier in patients with autism spectrum disorders and in their first-degree relatives.

Objectives: Intestinal permeability (IPT) was investigated in patients with autism as well as in their first-degree relatives to investigate leaky gut hypothesis. Faecal calprotectin (FC) was also measured in patients with autism, either with or without gastrointestinal symptoms, and in their first-degree relatives. Patients and Methods: IPT results, assessed by means of the lactulose/mannitol test, were compared with adult and child controls and with FC values. Results: A high percentage of abnormal IPT values were found among patients with autism (36.7%) and their relatives (21.2%) compared with normal subjects (4.8%). Patients with autism on a reported gluten-casein–free diet had significantly lower IPT values compared with those who were on an unrestricted diet and controls. Gastrointestinal symptoms were present in 46.7% of children with autism: constipation (45.5%), diarrhoea (34.1%), and others (alternating diarrhoea/constipation, abdominal pain, etc: 15.9%). FC was elevated in 24.4% of patients with autism and in 11.6% of their relatives; it was not, however, correlated with abnormal IPT values. Conclusions: The results obtained support the leaky gut hypothesis and indicate that measuring IPT could help to identify a subgroup of patients with autism who could benefit from a gluten-free diet. The IPT alterations found in first-degree relatives suggest the presence of an intestinal (tight-junction linked) hereditary factor in the families of subjects with autism.

Advanced Age Is an Independent Risk Factor for Severe Infections and Mortality in Patients Given Anti–Tumor Necrosis Factor Therapy for Inflammatory Bowel Disease

BACKGROUND & AIMS Few data are available on effects of biologic therapies in patients more than 65 years old with inflammatory bowel disease (IBD). We evaluated the risk and benefits of therapy with tumor necrosis factor (TNF) inhibitors in these patients. METHODS We collected data from patients with IBD treated with infliximab (n = 2475) and adalimumab (n = 604) from 2000 to 2009 at 16 tertiary centers. Ninety-five patients (3%) were more than 65 years old (52 men; 37 with ulcerative colitis and 58 with Crohns disease; 78 treated with infliximab and 17 with adalimumab). The control group comprised 190 patients 65 years old or younger who were treated with both biologics and 190 patients older than 65 years who were treated with other drugs. The primary end points were severe infection, cancer, or death. RESULTS Among patients more than 65 years old who received infliximab and adalimumab, 11% developed severe infections, 3% developed neoplasms, and 10% died. No variable was associated with severe infection or death. Among control patients more than 65 years old, 0.5% developed severe infections, 2% developed cancer, and 2% died. Among control patients less than 65 years old, 2.6% developed severe infections, none developed tumors, and 1% died. CONCLUSIONS Patients older than 65 years treated with TNF inhibitors for IBD have a high rate of severe infections and mortality compared with younger patients or patients of the same age that did not receive these therapeutics. The effects of anti-TNF agents in older patients with IBD should be more thoroughly investigated, because these patients have higher mortality related to hospitalization than younger patients.

Variants of CARD15 are associated with an aggressive clinical course of Crohn's disease--an IG-IBD study.

BACKGROUND:Three major variants of the CARD15 gene confer susceptibility to Crohns disease (CD). Whether or not these variants correlate with specific clinical features of the disease is under evaluation.AIM:We investigated the possible association of CARD15 variants with specific clinical characteristics, including the occurrence of anti-Saccharomyces cerevisiae antibodies (ASCA) and antineutrophil cytoplasmic antibodies (ANCA), in a large cohort of inflammatory bowel disease (IBD) patients and their unaffected relatives.METHODS:Three hundred and sixteen CD patients (156 with positive family history), 408 ulcerative colitis (UC) patients (206 with positive family history), 588 unaffected relatives, and 205 unrelated healthy controls (HC) were studied. Single nucleotide polymorphisms (SNPs) R702W, G908R, and L1007finsC of the CARD15 gene were investigated and correlated to age at diagnosis, gender, family history, localization, extraintestinal manifestations, previous resective surgery, stenosing/fistulizing pattern, ANCA, and ASCA.RESULTS:Compared to HC, the frequencies of all three variants in CD were significantly increased: 8.7%versus 4.1% for R702W (p < 0.006), 7.3%versus 2.7% for G908R (p < 0.002), 9.3%versus 0.7% for L1007finsC (p < 0.00001). At least one risk allele was found in 38.2% (p < 0.0001, compared to HC), 13.7% (NS), and 15.1% of CD, UC, and HC, respectively. The L1007finsC risk allele was also significantly increased in unaffected relatives of familial (9.5%; p < 0.00001), and sporadic CD (9%; p < 0.00001), compared to HC (0.7%). Sixteen healthy relatives, carriers of two risk alleles, were asymptomatic after 5–8 yr of follow-up. CD carriers of at least one variant were younger (p= 0.03), more likely to have ileal localization (p= 0.0001), stenosing pattern (p= 0.01), previous resective surgery (p= 0.0001), and presence of ASCA (p= 0.0001). No difference in SNPs frequency between familial and sporadic cases of CD was found.CONCLUSIONS:In our population, both familial and sporadic CD patients carrying at least one major variant of CARD15 had an aggressive clinical course.

Intestinal permeability in Crohn's disease patients and their first degree relatives.

BACKGROUND Family studies suggested that an altered intestinal permeability plays a role in the genesis of Crohns disease. AIM Aim of the present study was to investigate a possible genetic alteration of the mucosal barrier in Crohns disease. SUBJECTS 16 Crohns disease patients and 26 of their cohabiting first degree relatives were studied. METHODS To investigate intestinal permeability, Cellobiose/Mannitol test was administered to both groups. RESULTS In the two groups, we found that the median intestinal permeability values were higher and statistically different from those obtained in 32 healthy control subjects as well as in five healthy control families. Six (37.5%) Crohns disease patients and three (11.5%) of their first degree relatives showed increased individual intestinal permeability values. Intestinal permeability alteration in Crohns disease patients was unrelated to sex, age, disease activity, localisation, duration, treatment schedule, as well as to serum anti-Saccharomyces cervisiae antibody positivity in a pilot study conducted in 7 Crohns disease patients; anti-Saccharomyces cervisiae antibody values were negative in all 10 first degree relatives investigated. CONCLUSIONS These findings demonstrate the increase in IP in 37% of the patients and in 11% of their relatives. More extensive investigation of the correlation between ASCA alterations and IP will be needed in both patients with Crohns disease and their relatives.

Survival and causes of death in Italian patients with ulcerative colitis A GISC nation-wide study

BACKGROUND Death rate for patients with ulcerative colitis has changed over last few decades. Recent studies indicate that cumulative long-term mortality is comparable to that in general population, and that deaths may depend on causes not strictly related to colonic disease. AIM To evaluate overall and cause-specific mortality rate in a large group of Italian patients with ulcerative colitis. METHODS A total of 2,066 ulcerative colitis patients aged >18 years consecutively diagnosed in twenty Italian Gastroenterology Units between 1964 and 1995 were followed-up from diagnosis until 1997. Standardised Mortality Ratios and Relative Survival Ratios were calculated. RESULTS Overall mortality of patients with ulcerative colitis was comparable to that in general population with 93 deaths observed versus 92.1 expected (standardises mortality ratio, 1.0; 95% confidence interval, 0.8-1.2). Significantly higher mortality was observed in patients under 30 years of age at diagnosis (standardised mortality ratio, 2.7; 95% confidence interval, 1.3-4.9), and in those diagnosed before 1974 (standardised mortality ratio, 2.7; 95% confidence interval, 1.1-5.7). Proctocolitis and complications from surgery were mentioned in 11 and 5 certificates, respectively. A significant excess of deaths was observed for colorectal cancer (colon: standardised mortality ratio, 3.0; 95% confidence interval, 1.0-6.9; rectum: standardised mortality ratio, 4.4; 95% confidence interval, 1.2-11.3), and haemolymphopoietic neoplasms (standardised mortality ratio, 2.8; 95% confidence interval, 1.0-6.1), in particular multiple myeloma and non-Hodgkin lymphoma. A significant deficit of deaths was observed for cancer of the respiratory system (standardised mortality ratio, 0.3; 95% confidence interval, 0.1-1.0). CONCLUSIONS This study confirms that, also in Italy, mortality of patients with ulcerative colitis is comparable to that in general population. Only 12% of deaths were due to ulcerative colitis itself, whereas 10% of deaths were attributed to colorectal cancer. Deaths from colorectal cancer occurred, on average, 9 years after diagnosis of ulcerative colitis, suggesting that the risk of cancer is not limited to patients with long-standing colitis. As to mortality for causes unrelated to colitis, there was an excess of deaths due to malignancies of the haemolymphopoietic system.

Hepatobiliary alterations in patients with inflammatory bowel disease: a multicenter study. Caprilli & Gruppo Italiano Studio Colon-Retto.

BACKGROUND AND METHODS Four hundred and eighty-four patients with inflammatory bowel disease underwent clinical examination, ultrasonography, and biochemical liver function tests, to estimate the prevalence of hepatobiliary alterations. The patient group included patients without a history of liver disease. Controls were recruited from patients with functional symptoms. RESULTS More patients with ulcerative colitis than controls had liver steatosis and increased alkaline phosphatase levels. Factors increasing the probability of liver damage were long-standing disease, the presence of moderate/severe disease activity, and treatment with steroids and mesalazine. A significant association was found between biliary disease and long-standing colitis and also therapy with steroids and mesalazine. Alkaline phosphatase and aminotransferase levels were significantly higher in Crohns disease patients than in controls. Hepatic and biliary damage was found more commonly in the 1st year after diagnosis. CONCLUSIONS The monitoring of hepatobiliary function is suggested for patients with inflammatory bowel disease, even in the absence of symptoms and history.

Cancer in Crohn's Disease patients treated with infliximab: A long-term multicenter matched pair study

Background: The long‐term risk of neoplasia in Crohns disease (CD) patients treated with infliximab is undefined. The aim was to assess, in a multicenter, matched‐pair study, whether infliximab use in CD is associated with an increased frequency of neoplasia in the long term. Methods: A multicenter, long‐term, matched‐pair study was conducted in 12 referral inflammatory bowel disease (IBD) centers. An initial cohort of 808 CD patients, including 404 infliximab‐treated (CD‐IFX) and 404 matched CD controls never treated with infliximab (CD‐C) studied from 1999 to 2004, was followed up for an additional 4 years (2004–2008). Cases and controls were matched for: sex, age (±5 years), CD site, follow‐up (±5 years), immunosuppressant use, and CD duration (±5 years). From 1999 to 2008 the frequency and characteristics of neoplasia were compared between CD‐IFX and CD‐C. Results: In 2008, 591 patients (304 CD‐IFX, 287 CD‐C) were in follow‐up. Matched couples included 442 patients: 221 CD‐IFX and 221 CD‐C (median follow‐up, months: 72, range 48–114 versus 75, range 44–114). From 1999 to 2008 the frequency of neoplasia among the 591 patients did not differ between CD‐IFX (12/304; 3.94%) and CD‐C (12/287; 4.19%; P = 0.95). A comparable frequency of neoplasia was also observed between the 221 matched couples (CD‐IFX: 8/221; 3.61% versus CD‐C: 9/221; 4.07%; P = 1). No specific histotype of cancer appeared associated with infliximab use. Conclusions: The frequency of neoplasia was comparable in an adult population of CD patients treated or not with infliximab, matched for clinical variables and followed up for a median of 6 years. (Inflamm Bowel Dis 2011)

Randomized, controlled trial to compare the J-pouch and W-pouch configurations for ulcerative colitis in the maturation period.

PURPOSE: Proctocolectomy with ileal pouch-anal anastomosis has become the procedure of choice for the treatment of ulcerative colitis. Functional results may differ with different pouch designs. This randomized study aimed to evaluate the relative effectiveness of two-limb J and four-limb W reservoir designs in the so-called maturation period after ileostomy closure. METHODS: Twenty-four patients underwent ileal pouch-anal anastomosis for ulcerative colitis. Eleven were randomly assigned to the J-pouch group and 13 to the W-pouch group. Frequency of defecation and other functional data were collected at 4, 8, and 12 months after ileostomy closure. Maximum tolerated volume was assessed in the same period by a latex balloon inflated with water. Maximum resting anal pressure, maximum voluntary contraction, and the rectoanal inhibitory reflex were assessed in the preoperative period and at 4, 8, and 12 months after ileostomy closure. RESULTS: Frequency of defecation decreased from 4 to 12 months after ileostomy closure in both groups (P=0.04), but patients with a W-pouch had significantly lower values than patients with J-pouches (P<0.01). Night-time defecation (P=0.04) and use of antidiarrheals (P=0.04) were significantly lower for patients with a W-pouch. Maximum tolerated volume was greater in the W-pouch group throughout the whole period (P=0.01). Maximum resting anal pressure, maximum voluntary contraction, and rectoanal inhibitory reflex did not differ between the study arms CONCLUSION: Patients with W-pouch have better functional results than those with J-pouches in the “maturation period” after ileostomy closure.