Predictors of Outcome in Ulcerative Colitis.

BACKGROUND: Approximately 80% of patients with ulcerative colitis (UC) have intermittently active disease and up to 20% will require a colectomy, but little data available on predictors of poor disease course. The aim of this study was to identify clinical and genetic markers that can predict prognosis. METHODS: Medical records of patients with UC with ≥5 years of follow-up and available DNA and serum were retrospectively assessed. Immunochip was used to genotype loci associated with immune mediated inflammatory disorders (IMIDs), inflammatory bowel diseases, and other single nucleotide polypmorphisms previously associated with disease severity. Serum levels of pANCA, ASCA, CBir1, and OmpC were also evaluated. Requirement for colectomy, medication, and hospitalization were used to group patients into 3 prognostic groups. RESULTS: Six hundred one patients with UC were classified as mild (n = 78), moderate (n = 273), or severe disease (n = 250). Proximal disease location frequencies at diagnosis were 13%, 21%, and 30% for mild, moderate, and severe UC, respectively (P = 0.001). Disease severity was associated with greater proximal extension rates on follow-up (P < 0.0001) and with shorter time to extension (P = 0.03) and to prednisone initiation (P = 0.0004). When comparing severe UC with mild and moderate UC together, diagnosis age >40 and proximal disease location were associated with severe UC (odds ratios = 1.94 and 2.12, respectively). None of the single nucleotide polypmorphisms or serum markers tested was associated with severe UC, proximal disease extension or colectomy. CONCLUSIONS: Older age and proximal disease location at diagnosis, but not genetic and serum markers, were associated with a more severe course. Further work is required to identify biomarkers that will predict outcomes in UC.

Serological markers predict inflammatory bowel disease years before the diagnosis.

OBJECTIVE: Anti-neutrophil cytoplasmic antibodies and anti-Saccharomyces cerevisiae mannan antibodies (ASCAs) have been detected in the serum of patients with ulcerative colitis (UC) and Crohn's disease (CD) and their unaffected family members. The aim of this study was to establish the value of serological markers as predictors of UC and CD. DESIGN: Individuals who developed CD or UC were identified from the European Prospective Investigation into Cancer and Nutrition (EPIC) study. At recruitment, none of the participants had a diagnosis of CD or UC. For each incident case, two controls were randomly selected matched for centre, date of birth, sex, date of recruitment and time of follow-up. Serum of cases and controls obtained at recruitment were analysed for ASCA IgG, ASCA IgA, perinuclear anti-neutrophil cytoplasmic antibody (pANCA), antibodies against Escherichia coli outer membrane porin C (OmpC) and flagellin CBir1. Conditional logistic regression was used to determine risk of CD and UC. Receiver operating characteristic curves were constructed to test accuracy. RESULTS: A total of 77 individuals were diagnosed with CD and 167 with UC after a mean follow-up of 4.5 (SD 3.2) and 4.4 (SD 3.1) years following blood collection, respectively. Combinations of pANCA, ASCA, anti-CBir1 and anti-OmpC were most accurate in predicting incident CD and UC (area under curve 0.679 and 0.657, respectively). The predictive value of the combination of markers increased when time to diagnosis of CD or UC decreased. CONCLUSION: A panel of serological markers is able to predict development of CD and UC in individuals from a low-risk population.

Serum interleukin-1ß, interleukin-8 and anti-heat shock 60 Chlamydia trachomatis antibodies as markers of ectopic pregnancy.

Anti-Chlamydial trachomatis (anti-CT) responses, particularly anti-heat shock 60 (Hsp60), antibodies confer a higher risk of ectopic pregnancy. With emerging evidence supporting the pivotal role of interleukin-1ß (IL-1ß) and IL-8 in the immunopathogenesis of CT-specific tubal obstruction, we determined anti-CT Hsp60 antibody reactivity and serum concentrations of IL-1ß and IL-8 in failed pregnancies consisting of 30 consecutive ectopic pregnancies and 30 missed abortions, with 32 viable intrauterine pregnancies tested as normal controls. ELISAs were utilised to measure IgA or IgG anti-CT major outer membrane outer protein (MOMP) antibodies, IgG anti-CT Hsp60 antibodies and IL-1ß and IL-8. IgG anti-CT Hsp60 antibodies were more prevalent in ectopic pregnancy cases (43.3%, 13/30) than in intrauterine pregnancies (16%, 5/32, p=0.016). All 13 ectopic pregnancy anti-CT Hsp60-positive cases had anti-CT MOMP antibodies. CT-specific antibodies were more frequent in merged ectopic pregnancy and missed abortions cases (35%, 21/60) than in intrauterine pregnancies (16%, p=0.049). The median (range) levels of IL-1ß in ectopic pregnancy, missed abortions and normal intrauterine pregnancies were 1.74 (0.2-8.7), 1.14 (0.2-16) and 1.22 (0.2-16.2) pg/ml, respectively (p>0.05, for all). Serum IL-8 levels were comparable amongst groups: ectopic pregnancy (median [range]: 25.1 [18.3-1000]); missed abortions (32.9 [15.39-1000]); and intrauterine pregnancies (25.11 [18.3-1000] pg/ml). Anti-CT antibody-positive ectopic pregnancy had significantly lower IL-1ß levels (1.29 [0.2-2.93]) pg/ml than sero-negative ectopic pregnancy cases (2.09 [1.10-8.70]) pg/ml, (p=0.022), but IL-8 did not differ. Our data demonstrate that anti-CT Hsp60 immunity is a predominant feature of ectopic pregnancy. We conclude that neither IL-1ß nor IL-8 can be considered markers of failed pregnancy, although lower levels of the former cytokine are associated with CT-related ectopic pregnancy.

[Possible pathogenic role of vascular, immunologic and genetic factors in certain gastroenterologic disorders]. / Vascularis, immunológiai és genetikai tényezok lehetséges patogenetikai szerepe néhány gasztroenterológiai kórképben.

Clinical presentations of the celiac disease and inflammatory bowel diseases (IBD) are highly variable, but little is known about those factors determining disease phenotype. Since differences in the antioxidant, scavenging and immunomodulatory properties were found among 3 major haptoglobin (Hp) phenotypes. The aim of our study was to investigate the distribution of Hp polymorphisms in large cohort celiac patients and in patients with IBD, and also their possible association with the clinical presentation of these diseases. Hp phenotypes were determined by sodium-dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting of the sera, which clearly identifies the genotypes. In celiac patients, the frequency of Hp 2-1 phenotypes was significantly higher compared to the control population. The occurrence of Hp 2-2 was lower; however, patients having this phenotype were at an increased risk of severe malabsorption as a clinical presentation of the disease but reduced risk of silent disease. In Crohn's disease (CD), patients with Hp 2-1 type carried a higher probability for inflammatory form compared to the other two phenotypes, while the stricturing form developed less frequently. In patients with primary sclerosing cholangitis we found no Hp 1-1 expression. The role of Hp molecules may be explained by their distinct immunomodulatory properties and structural characteristics. Sero-reactivity to microbial components or perinuclear components of neutrophils (atypical P-ANCA) is reported to be associated with disease phenotype and may be of diagnostic importance in IBD. The aim of our study was to investigate the prevalence of serological markers in a large cohort of IBD patients. We also assessed the possible interaction with the disease phenotype and studied the relationship between serological response and genetic factors. Sera were assayed for Saccharomyces cerevisiae (ASCA) and outer membrane porin protein of Escherichia coli (anti-Omp) by enzyme-linked immunosorbent assay (ELISA) and ANCA by indirect immunofluorescence method. Serological markers proved to be useful in differential diagnosis of IBD. In a logistic regression analysis, ASCA and anti-Omp were independently associated with ileal and non-inflammatory disease, but not with a risk for surgery. The number of antibodies produced against microbial antigen and their titers in CD showed a positive correlation with the small bowel involvement and the severity of the disease course (serology dosage effect). Reactivity to microbial components was associated with caspase recruitment domain (NOD2/CARD15) genotype. Positive correlation was found between the number of mutations and the prevalence of antimicrobial antibodies (gene dosage effect), further supporting the role of altered microbial sensing in the pathogenesis of CD.

Serum immune responses predict rapid disease progression among children with Crohn's disease: immune responses predict disease progression.

BACKGROUND AND AIM: Crohn's disease (CD) is a heterogeneous disorder characterized by diverse clinical phenotypes. Childhood-onset CD has been described as a more aggressive phenotype. Genetic and immune factors may influence disease phenotype and clinical course. We examined the association of immune responses to microbial antigens with disease behavior and prospectively determined the influence of immune reactivity on disease progression in pediatric CD patients. METHODS: Sera were collected from 196 pediatric CD cases and tested for immune responses: anti-I2, anti-outer membrane protein C (anti-OmpC), anti-CBir1 flagellin (anti-CBir1), and anti-Saccharomyces-cerevisiae (ASCA) using ELISA. Associations between immune responses and clinical phenotype were evaluated. RESULTS: Fifty-eight patients (28%) developed internal penetrating and/or stricturing (IP/S) disease after a median follow-up of 18 months. Both anti-OmpC (p < 0.0006) and anti-I2 (p < 0.003) were associated with IP/S disease. The frequency of IP/S disease increased with increasing number of immune responses (p trend = 0.002). The odds of developing IP/S disease were highest in patients positive for all four immune responses (OR (95% CI): 11 (1.5-80.4); p = 0.03). Pediatric CD patients positive for > or =1 immune response progressed to IP/S disease sooner after diagnosis as compared to those negative for all immune responses (p < 0.03). CONCLUSIONS: The presence and magnitude of immune responses to microbial antigens are significantly associated with more aggressive disease phenotypes among children with CD. This is the first study to prospectively demonstrate that the time to develop a disease complication in children is significantly faster in the presence of immune reactivity, thereby predicting disease progression to more aggressive disease phenotypes among pediatric CD patients.

Serologic responses in indeterminate colitis patients before ileal pouch-anal anastomosis may determine those at risk for continuous pouch inflammation.

PURPOSE: Although acute pouchitis after ileal pouch-anal anastomosis is common and easily treated, continuous pouch inflammation seen clinically as chronic, antibiotic-dependent pouchitis, and/or Crohn's disease remains a difficult management problem. Compared with ulcerative colitis, indeterminate colitis patients undergoing ileal pouch-anal anastomosis have a higher incidence of continuous pouch inflammation, which may represent persistent immune reactivity to microbial antigens. Antibody responses to three microbial antigens (oligomannan anti-Saccharomyces cerevisiae, outer membrane porin C of Escherichia coli, and an antigen (I2) from Pseudomonas flourescens) are more commonly seen in Crohn's disease, whereas antibodies to a cross-reactive antigen (perinuclear antineutrophil cytoplasmic antibodies) is more suggestive of ulcerative colitis. We examined whether preoperative serologic responses to these antigens were associated with Crohn's disease in indeterminate colitis patients after ileal pouch-anal anastomosis. METHODS: Twenty-eight indeterminate colitis patients undergoing ileal pouch-anal anastomosis were prospectively assessed for the development of pouchitis or Crohn's disease. Serologic responses were determined by enzyme-linked immunosorbent assay and immunofluorescence. Patients were classified based on four predominant profiles of antibody expression. Antibody profiles were determined before knowledge of clinical outcome. RESULTS: Median follow-up was 38 (range, 3-75) months. Of 16 patients (61 percent) who developed pouch inflammation, 4 (25 percent) had acute pouchitis and 12 (75 percent) had continuous pouch inflammation (9 had chronic pouchitis, 3 had Crohn's disease). No preoperative clinical factor predicted the development of these pouch complications. Overall, 16 patients (57 percent) had a positive antibody reactivity profile. Serologic expression of any marker alone did not predict the development of continuous pouch inflammation. However, continuous pouch inflammation developed in 10 of 16 patients (63 percent) who had a positive antibody reactivity profile compared with only 2 of 12 patients (17 percent) who had a negative antibody reactivity profile (P = 0.015). CONCLUSIONS: Indeterminate colitis patients who have a positive antibody reactivity profile before ileal pouch-anal anastomosis have a significantly higher incidence of continuous pouch inflammation after surgery than those with a negative profile.

Serologic markers in inflammatory bowel disease: state of the art.

A variety of serologic tests are emerging that are relevant to the diagnosis and treatment of Crohn's disease and ulcerative colitis. These laboratory tests include: anti-neutrophil cytoplasmic antibody with perinuclear staining (pANCA); anti-Saccharomyces cerevisiae antibody (ASCA); outer membrane porin C (Omp C); and I2 antibody (novel homologue of the bacterial transcription-factor families). The potential roles for serologic testing for inflammatory bowel disease (IBD) include adjunctive diagnostic testing in patients with known IBD, screening testing for IBD in patients with compatible gastrointestinal symptoms, and serving as a marker of unique disease course or prediction of response to specific treatments. This article reviews the use of pANCA, ASCA, I2, and Omp C in patients with IBD.

Anti-Saccharomyces cerevisiae antibody (ASCA) positivity is associated with increased risk for early surgery in Crohn's disease.

BACKGROUND: Anti-Saccharomyces cerevisiae antibodies (ASCA) are a specific but only moderately sensitive diagnostic marker for Crohn's disease. We sought to explore the role of ASCA as a prognostic marker for aggressive disease phenotype in Crohn's disease. AIMS: To determine the role of ASCA status as a risk factor for early surgery in Crohn's disease. SUBJECTS: We performed a case control study in a cohort of patients, newly diagnosed with Crohn's disease, between 1991 and 1999. All patients were followed for at least three years. Case subjects (n = 35) included those who had major surgery for Crohn's disease within three years of diagnosis. Controls (n = 35) included patients matched to cases for age, sex, disease location, and smoking status, and who did not undergo major surgery for Crohn's disease within three years of diagnosis. METHODS: Blinded assays were performed on serum for ASCA (immunoglobulin (Ig)A and IgG). A paired analysis of cases-controls was performed to test for the association between ASCA status and risk of early surgery. RESULTS: ASCA IgA was strongly associated with early surgery (odds ratio (OR) 8.5 (95% confidence interval (CI) 2.0-75.9); p = 0.0013). ASCA IgG+ and ASCA IgG+/IgA+ patients were also at increased risk for early surgery (OR 5.5 (95% CI 1.2-51.1), p = 0.0265; and OR 5.0 (95% CI 1.1-46.9), p = 0.0433, respectively). The association between ASCA and early surgery was evident in patients requiring surgery for ileal or ileocolonic disease. CONCLUSIONS: Patients with Crohn's disease who are positive for ASCA IgA, IgG, or both, may define a subset of patients with Crohn's disease at increased risk for early surgery.

Investigation of the pore-forming mechanism of a cytolytic delta-endotoxin from Bacillus thuringiensis.

Cyt2Aa1 is a cytolytic protein produced by Bacillus thuringiensis subsp. kyushuensis. Penetration of the toxin into membranes has been studied to learn more about membrane-insertion mechanisms and transmembrane-pore formation. The haemolysis assay of Cyt2Aa1 showed a steep and sigmoidal dose-response curve, indicating that toxin aggregation or oligomerization is required for pore formation. Studies of the effect of temperature on pore formation and fluorimetric studies of acrylodan-labelled toxin suggest that toxin inserts into the membrane before oligomerizing to form a pore. Low temperature neither inhibited membrane binding nor closed pores that have been formed, but markedly inhibited oligomerization of the toxin molecules. When toxin-treated red blood cells at 4 degrees C were transferred to a toxin-free solution at 37 degrees C, no significant increase in haemolysis was observed. This result suggests that membrane-bound toxin could not diffuse laterally and interact with other molecules to form a pore. From these results, we propose that Cyt2Aa1 binds and inserts into the membrane as a monomer. Oligomerization occurs when toxin molecules have bound in close proximity to each other and pores are formed from large oligomers.