M1115 Comparison of Gut Mucosal Response to Food Antigen Injection with Serum IgG Food Antibodies in...
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ulcerative colitis (UC) and Mb Crohn (MB) patients were tested using t-tests or non paramet- rical tests, as appropriate. All statistical analyses were carried out using SPSS 11.0 (SSPS inc., Chicago, IL, USA) statistical software package. RESULTS: We tested 41 cases (28 with MC and 13 with UC) and 39 controls. Among patients, 4 of them had elastase levels indicative of pancreatic insufficiency (<200 ug); 2 patients with UC and 2 patients with MC. All controls had normal level of elastase-1. Overall, we found significant differences in mean levels of stool elastase between cases and controls. No differences in stool elastase means +/- SD were found comparing MC and UC (Mean Elastase +/- SD in stool among patients with UC vs MC were 611.86 +/- 101.91 vs. 726.25+/- 51.58, respectively, t-test t=-1.117, p=0.271). No significant differences were found regarding to gender in patients and controls. CONCLUSION: Finding pancreatic insufficiency in 10,89% of the included patients suggests association between IBD and PI. Further investigations have to be done to answer which factors are responsible for impaired pancreatic function in IBD. M1114 The Prevalence and Discrimination Value of Perinuclear Antineutrophil Cytoplasmic Antibodies and Anti-Saccharomyces Cerevisiae Antibodies in a Chinese Inflammatory Bowel Disease Cohort in Central China Feng Zhou, Fubing Wang, Umid K. Shrestha, Hongling Wang, Zhitao Chen, Jin Li, Bing Xia Background and aims Perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti- Saccharomyces cerevisiae antibodies (ASCA) has been suggested as a diagnostic approach in inflammatory bowel disease (IBD) in Western countries. The present study aimed to determine the prevalence of pANCA and ASCA in Chinese patients with IBD and to evaluate their discriminative ability between ulcerative colitis (UC) and Crohn's disease (CD) in a Chinese cohort in central China. Methods One hundred and fifty-six well-characterized, unrelated, consecutive Chinese patients with IBD (126 with UC, 30 with CD) and 60 age and sex matched healthy controls were included in the study. Serum pANCA and ASCA were assayed by standardized indirect immunofluorescence methods. Clinical phenotypes of the patients were obtained from the medical charts. Results The prevalence of pANCA was 42.9% in patients with UC, 13.3% in CD (P<0.01) and 5% in healthy controls (P<0.01), while the prevalence of ASCA was 46.7% in patients with CD, 15.9% in CD (P<0.05) and 5% in healthy controls (P<0.01). Sensitivity, specificity, positive and negative predictive values of the pANCA test were 43%, 87%, 93%, and 27%, respectively for UC. A combination of positive pANCA and negative ASCA was more accurate than the pANCA test alone. Positive pANCA was associated with phenotype of severe and extensive UC. ASCA test yielded 47% of sensitivity, 84% specificity, 41% positive and 87% negative predictive values for CD. The combination of positive ASCA and negative pANCA did not change these values significantly. Conclusions pANCA was more prevalent in UC and ASCA was more prevalent in CD. Both are specific to discriminate for UC and CD in an IBD cohort in central China. Acknowledgement The study was supported by grants from the state public health project of China (200802156) and Hubei provincial center for clinical study of colorectal dis- eases (2008) M1115 Comparison of Gut Mucosal Response to Food Antigen Injection with Serum IgG Food Antibodies in Crohn's Disease Stephen J. Inns, Farooq Rahman, Stuart L. Bloom, Anton V. Emmanuel Background: Controversy surrounds the issue of food sensitivity in Crohn's disease (CD), but tools to measure this are poor. Mucosal provocation tests are attractive in being directly interpretable whilst reducing the subjectivity inherent in interpreting a patient's perceived response. The aim of this study was to correlate the colonic mucosal response to food antigen provocation in CD with serum IgG reactivity, patient perceived intolerance and intestinal permeability. Methods: 12 patients with quiescent CD not involving the rectum were exam- ined using flexible sigmoidoscopy and rectal mucosal provocation using one control and 5 food antigen injections. The mucosal reaction was measured using laser doppler flowmetry (LDF) 3.5 hours after injection. Each patient also completed a questionnaire regarding food sensitivities, had intestinal permeability measured and had serum testing for IgG antibodies to foods. Results: There was no change in mean LDF for the control site injection but there was an increase in LDF for each of the food antigen injection sites. This change was statistically significant (Bonferroni-corrected) for yeast (p<0.001) and milk (p<0.003). However, there was no correlation between that change and either serum IgG reactivity for the tested foods, or patient reported sensitivity to the tested foods or intestinal permeability. Conclusion: This study confirms the practicality of performing antigen provocation testing in patients with CD, and demonstrates that patients exhibit greater mucosal hyperaemia in response to food antigen injection than in response to control injection. The mechanism for this phenomenon merits further investigation since there is no association with serum IgG reactivity to foods, patient reported food intolerance or intestinal permeability. M1116 Evaluation of Perinuclear Antineutrophil Cytoplasmic Autoantibodies (P- ANCA) and Anti-Saccharomyces Cerevisiae Antibodies (ASCA) in Inflammatory Bowel Disease in a Reference Center in Brazil Aderson O. Damiao, Fernando Schappo, Cleonice Bueno, Maria Laura Lacava Lordello, André Z. Leite, Maraci Rodrigues, Carmen L. Ortiz-Agostinho, Iêda Nishitokukado, Fabiana M. Santos, Debora D. Poli, Aytan M. Sipahi The determination of the serological markers P-ANCA and ASCA assists as non-invasive strategies on the inflammatory bowel disease (IBD) diagnosis. The most associated pattern to ulcerative colitis (UC) occurs with ASCA- (negative) and P-ANCA + (positive). In Crohn's disease (CD) is the opposite, that is, ASCA+ and P-ANCA-. Sensitivity and specificity of these markers in the diagnosis of UC and CD have varied substantially and, in addition to methodological issues, there is the possibility of ethnic group variation (Lawrance et al. Am A-353 AGA Abstracts J Gastroenterol 2004; 99: 2186-2194). Thus, it is worthwhile to get some insights on the performance of these markers in a developing country like Brazil. Material and Methods - Serum samples were obtained from 200 patients for analysis of P-ANCA and ASCA, being 98 with UC and 102 with CD. The control group was represented by 54 healthy individuals. Determination of P-ANCA was performed by means of an indirect immunofluorescence assay, using ethanol-fixed neutrophil slides and ASCA was measured by ELISA. Results: P- ANCA prevalence found in UC, CD and the control group were 61,2%, 16,7% and 5,6%, respectively. ASCA prevalence in CD, UC and the control group were 52,9%, 27,6% and 5,6%, respectively. Sensitivity and specificity achieved using ASCA+/P-ANCA- pattern for CD were 45,1% and 89%, respectively. P-ANCA+/ASCA- pattern for UC were 43,9% and 91,2% respectively. A correlation was obtained between ASCA positive CD and use of immunosuppressants, including infliximabe (p=0,008). Other correlations (clinical and demographic) were not statistically different. Conclusions: The determination of antibodies P-ANCA and ASCA in IBD gets low sensitivity but high specificity, as demonstrated in other published reports. The correlation of these markers with clinical characteristics appears to be limited to a subset of patients with Crohn's disease, in whom a positive ASCA implies in increased consumption of immunosuppressants. M1117 Seroreactivity to Faecalibacterium Prausnitzii and the Presence of This Microorganism in Feces of Crohn's Disease Patients and Controls Nathalie Vermeulen, Marie Joossens, Severine Vermeire, Paul J. Rutgeerts, Xavier Bossuyt Introduction: Crohn's disease (CD) and ulcerative colitis (UC) are considered to originate from an aberrant immune response towards commensal bacteria in the gut in genetically predisposed patients. An imbalance of beneficial and detrimental commensal organisms, called dysbiosis, has been observed in IBD patients. Up to 80% of IBD patients show reactivity to bacterial components in their serum. A reduction of Faecalibacterium prausnitzii has recently been reported in CD patients. Aim: We evaluated whether patients with IBD show seroreactivity to F. prausnitzii and whether this reactivity is related to the presence of F. prausnitzii in fecal samples. Methods: We separated a total protein extract of F. prausnitzii on 2D gel elektrophoresis and blotted serum of 4 UC patients, 8 CD patients and 8 healthy controls. We also examined DGGE profiles of fecal bacteria in 4 CD patients and 4 age and sex matched controls. We identified a band on DGGE gel as F. prausnitzii by sequencing. Results: We found seroreactivity against several proteins in UC patients, CD patients, and healthy controls. No clear differences could be observed between the different groups, except for one prominent spot which was detected on western blots in 3 of 4 UC patients and in 6 of 8 CD patients. A very faint spot was observed in 1 of 8 healthy controls. F. prausnitzii was present in feces of 3 of the 4 CD patients and in all healthy controls. Interestingly, the same patient which lacked the band corresponding to F. prausnitzii on DGGE also lacked the prominent spot on western blot analysis. Conclusion: Blotting of serum against a protein extract of F. prausnitzii revealed strong seroreactivity against one protein in 9 of 12 patients with IBD which was not found in healthy control sera. Absence of this seroreactivity in one patient with Crohn's disease correlated with absence of the bacterium on DGGE analysis of the fecal flora. Identification of this protein might allow to understand why this bacterium exhibiting anti-inflammatory effects is found in reduced amounts in the feces of patients with IBD. M1118 Presence of Serum Antibodies Against Secreted Proteins from Mycobacterium avium Spp Paratuberculosis in Patients with Crohn's Disease Hin Hin Ko, Horacio Bach, Eran A. Raizman, Robert A. Enns, Brian Bressler Background. Mycobacterium avium spp. paratuberculosis (MAP) is the etiological agent of Johne's disease, an inflammatory bowel disease in domestic cattle that shows a striking resemblance to Crohn's disease (CD). Previous studies have shown that in order to survive, pathogenic mycobacteria secrete an abundant amount of proteins within macrophages, which interfere with the host immune response. Therefore, the purpose of this study is to determine the presence of antibodies against one such specific mycobacterial antigen in serum of patients with CD. Patients & Methods. Serum samples from 20 CD patients and 20 controls from a single, tertiary ambulatory care centre were collected. The presence of antibodies against specific antigen was determined by ELISA. Linear regression was used to assess the association of CD, sex, and age. Results. The average age for CD patients and controls were 41±14 and 46±18 years. 37.5% were males. In CD group, the mean Harvey Bradshaw Index score was 5.2±5.0 and the mean time since diagnosis of CD was 10.4±10.2 years. The mean antibody intensity readings for CD patients and controls are 0.513 and 0.355, respectively. The diagnosis of CD and female sex were independently associated with higher antibody intensity readings (p<0.01). Conclusions. Patients with CD have a significant higher level of antibodies against a specific mycobacterial antigen compared to people without CD. The relevance of this finding may provide further insight into the pathophysiology of CD and MAP's influence on this process. Whether this assay might be a more sensitive one compared to other antibodies previously used for detection of MAP in CD patients, will be examined in a larger cohort. AGA Abstracts
Transcript of M1115 Comparison of Gut Mucosal Response to Food Antigen Injection with Serum IgG Food Antibodies in...
ulcerative colitis (UC) and Mb Crohn (MB) patients were tested using t-tests or non paramet-rical tests, as appropriate. All statistical analyses were carried out using SPSS 11.0 (SSPSinc., Chicago, IL, USA) statistical software package. RESULTS: We tested 41 cases (28 withMC and 13 with UC) and 39 controls. Among patients, 4 of them had elastase levelsindicative of pancreatic insufficiency (<200 ug); 2 patients with UC and 2 patients withMC. All controls had normal level of elastase-1. Overall, we found significant differences inmean levels of stool elastase between cases and controls. No differences in stool elastasemeans +/- SD were found comparing MC and UC (Mean Elastase +/- SD in stool amongpatients with UC vs MC were 611.86 +/- 101.91 vs. 726.25+/- 51.58, respectively, t-testt=-1.117, p=0.271). No significant differences were found regarding to gender in patientsand controls. CONCLUSION: Finding pancreatic insufficiency in 10,89% of the includedpatients suggests association between IBD and PI. Further investigations have to be doneto answer which factors are responsible for impaired pancreatic function in IBD.
M1114
The Prevalence and Discrimination Value of Perinuclear AntineutrophilCytoplasmic Antibodies and Anti-Saccharomyces Cerevisiae Antibodies in aChinese Inflammatory Bowel Disease Cohort in Central ChinaFeng Zhou, Fubing Wang, Umid K. Shrestha, Hongling Wang, Zhitao Chen, Jin Li, BingXia
Background and aims Perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) has been suggested as a diagnostic approachin inflammatory bowel disease (IBD) in Western countries. The present study aimed todetermine the prevalence of pANCA and ASCA in Chinese patients with IBD and to evaluatetheir discriminative ability between ulcerative colitis (UC) and Crohn's disease (CD) in aChinese cohort in central China. Methods One hundred and fifty-six well-characterized,unrelated, consecutive Chinese patients with IBD (126 with UC, 30 with CD) and 60 ageand sex matched healthy controls were included in the study. Serum pANCA and ASCAwere assayed by standardized indirect immunofluorescence methods. Clinical phenotypesof the patients were obtained from the medical charts. Results The prevalence of pANCAwas 42.9% in patients with UC, 13.3% in CD (P<0.01) and 5% in healthy controls (P<0.01),while the prevalence of ASCA was 46.7% in patients with CD, 15.9% in CD (P<0.05) and5% in healthy controls (P<0.01). Sensitivity, specificity, positive and negative predictivevalues of the pANCA test were 43%, 87%, 93%, and 27%, respectively for UC. A combinationof positive pANCA and negative ASCA was more accurate than the pANCA test alone.Positive pANCA was associated with phenotype of severe and extensive UC. ASCA testyielded 47% of sensitivity, 84% specificity, 41% positive and 87% negative predictive valuesfor CD. The combination of positive ASCA and negative pANCA did not change these valuessignificantly. Conclusions pANCA was more prevalent in UC and ASCA was more prevalentin CD. Both are specific to discriminate for UC and CD in an IBD cohort in central China.Acknowledgement The study was supported by grants from the state public health projectof China (200802156) and Hubei provincial center for clinical study of colorectal dis-eases (2008)
M1115
Comparison of Gut Mucosal Response to Food Antigen Injection with SerumIgG Food Antibodies in Crohn's DiseaseStephen J. Inns, Farooq Rahman, Stuart L. Bloom, Anton V. Emmanuel
Background: Controversy surrounds the issue of food sensitivity in Crohn's disease (CD),but tools to measure this are poor. Mucosal provocation tests are attractive in being directlyinterpretable whilst reducing the subjectivity inherent in interpreting a patient's perceivedresponse. The aim of this study was to correlate the colonic mucosal response to food antigenprovocation in CD with serum IgG reactivity, patient perceived intolerance and intestinalpermeability. Methods: 12 patients with quiescent CD not involving the rectum were exam-ined using flexible sigmoidoscopy and rectal mucosal provocation using one control and 5food antigen injections. The mucosal reaction was measured using laser doppler flowmetry(LDF) 3.5 hours after injection. Each patient also completed a questionnaire regarding foodsensitivities, had intestinal permeability measured and had serum testing for IgG antibodiesto foods. Results: There was no change in mean LDF for the control site injection but therewas an increase in LDF for each of the food antigen injection sites. This change was statisticallysignificant (Bonferroni-corrected) for yeast (p<0.001) and milk (p<0.003). However, therewas no correlation between that change and either serum IgG reactivity for the tested foods,or patient reported sensitivity to the tested foods or intestinal permeability. Conclusion:This study confirms the practicality of performing antigen provocation testing in patientswith CD, and demonstrates that patients exhibit greater mucosal hyperaemia in responseto food antigen injection than in response to control injection. The mechanism for thisphenomenon merits further investigation since there is no association with serum IgGreactivity to foods, patient reported food intolerance or intestinal permeability.
M1116
Evaluation of Perinuclear Antineutrophil Cytoplasmic Autoantibodies (P-ANCA) and Anti-Saccharomyces Cerevisiae Antibodies (ASCA) inInflammatory Bowel Disease in a Reference Center in BrazilAderson O. Damiao, Fernando Schappo, Cleonice Bueno, Maria Laura Lacava Lordello,André Z. Leite, Maraci Rodrigues, Carmen L. Ortiz-Agostinho, Iêda Nishitokukado,Fabiana M. Santos, Debora D. Poli, Aytan M. Sipahi
The determination of the serological markers P-ANCA and ASCA assists as non-invasivestrategies on the inflammatory bowel disease (IBD) diagnosis. The most associated patternto ulcerative colitis (UC) occurs with ASCA- (negative) and P-ANCA + (positive). In Crohn'sdisease (CD) is the opposite, that is, ASCA+ and P-ANCA-. Sensitivity and specificity ofthese markers in the diagnosis of UC and CD have varied substantially and, in addition tomethodological issues, there is the possibility of ethnic group variation (Lawrance et al. Am
A-353 AGA Abstracts
J Gastroenterol 2004; 99: 2186-2194). Thus, it is worthwhile to get some insights on theperformance of these markers in a developing country like Brazil. Material and Methods -Serum samples were obtained from 200 patients for analysis of P-ANCA and ASCA, being98 with UC and 102 with CD. The control group was represented by 54 healthy individuals.Determination of P-ANCA was performed by means of an indirect immunofluorescenceassay, using ethanol-fixed neutrophil slides and ASCA was measured by ELISA. Results: P-ANCA prevalence found in UC, CD and the control group were 61,2%, 16,7% and 5,6%,respectively. ASCA prevalence in CD, UC and the control group were 52,9%, 27,6% and5,6%, respectively. Sensitivity and specificity achieved using ASCA+/P-ANCA- pattern forCD were 45,1% and 89%, respectively. P-ANCA+/ASCA- pattern for UC were 43,9% and91,2% respectively. A correlation was obtained between ASCA positive CD and use ofimmunosuppressants, including infliximabe (p=0,008). Other correlations (clinical anddemographic) were not statistically different. Conclusions: The determination of antibodiesP-ANCA and ASCA in IBD gets low sensitivity but high specificity, as demonstrated in otherpublished reports. The correlation of these markers with clinical characteristics appears tobe limited to a subset of patients with Crohn's disease, in whom a positive ASCA impliesin increased consumption of immunosuppressants.
M1117
Seroreactivity to Faecalibacterium Prausnitzii and the Presence of ThisMicroorganism in Feces of Crohn's Disease Patients and ControlsNathalie Vermeulen, Marie Joossens, Severine Vermeire, Paul J. Rutgeerts, Xavier Bossuyt
Introduction: Crohn's disease (CD) and ulcerative colitis (UC) are considered to originatefrom an aberrant immune response towards commensal bacteria in the gut in geneticallypredisposed patients. An imbalance of beneficial and detrimental commensal organisms,called dysbiosis, has been observed in IBD patients. Up to 80% of IBD patients show reactivityto bacterial components in their serum. A reduction of Faecalibacterium prausnitzii hasrecently been reported in CD patients. Aim: We evaluated whether patients with IBD showseroreactivity to F. prausnitzii and whether this reactivity is related to the presence of F.prausnitzii in fecal samples. Methods: We separated a total protein extract of F. prausnitziion 2D gel elektrophoresis and blotted serum of 4 UC patients, 8 CD patients and 8 healthycontrols. We also examined DGGE profiles of fecal bacteria in 4 CD patients and 4 age andsex matched controls. We identified a band on DGGE gel as F. prausnitzii by sequencing.Results: We found seroreactivity against several proteins in UC patients, CD patients, andhealthy controls. No clear differences could be observed between the different groups, exceptfor one prominent spot which was detected on western blots in 3 of 4 UC patients and in6 of 8 CD patients. A very faint spot was observed in 1 of 8 healthy controls. F. prausnitziiwas present in feces of 3 of the 4 CD patients and in all healthy controls. Interestingly, thesame patient which lacked the band corresponding to F. prausnitzii on DGGE also lackedthe prominent spot on western blot analysis. Conclusion: Blotting of serum against a proteinextract of F. prausnitzii revealed strong seroreactivity against one protein in 9 of 12 patientswith IBD which was not found in healthy control sera. Absence of this seroreactivity in onepatient with Crohn's disease correlated with absence of the bacterium on DGGE analysis ofthe fecal flora. Identification of this protein might allow to understand why this bacteriumexhibiting anti-inflammatory effects is found in reduced amounts in the feces of patientswith IBD.
M1118
Presence of Serum Antibodies Against Secreted Proteins from Mycobacteriumavium Spp Paratuberculosis in Patients with Crohn's DiseaseHin Hin Ko, Horacio Bach, Eran A. Raizman, Robert A. Enns, Brian Bressler
Background. Mycobacterium avium spp. paratuberculosis (MAP) is the etiological agent ofJohne's disease, an inflammatory bowel disease in domestic cattle that shows a strikingresemblance to Crohn's disease (CD). Previous studies have shown that in order to survive,pathogenic mycobacteria secrete an abundant amount of proteins within macrophages, whichinterfere with the host immune response. Therefore, the purpose of this study is to determinethe presence of antibodies against one such specific mycobacterial antigen in serum ofpatients with CD. Patients & Methods. Serum samples from 20 CD patients and 20 controlsfrom a single, tertiary ambulatory care centre were collected. The presence of antibodiesagainst specific antigen was determined by ELISA. Linear regression was used to assess theassociation of CD, sex, and age. Results. The average age for CD patients and controls were41±14 and 46±18 years. 37.5% were males. In CD group, the mean Harvey Bradshaw Indexscore was 5.2±5.0 and the mean time since diagnosis of CD was 10.4±10.2 years. The meanantibody intensity readings for CD patients and controls are 0.513 and 0.355, respectively.The diagnosis of CD and female sex were independently associated with higher antibodyintensity readings (p<0.01). Conclusions. Patients with CD have a significant higher levelof antibodies against a specific mycobacterial antigen compared to people without CD. Therelevance of this finding may provide further insight into the pathophysiology of CD andMAP's influence on this process. Whether this assay might be a more sensitive one comparedto other antibodies previously used for detection of MAP in CD patients, will be examinedin a larger cohort.
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