Frank Seibold

Genome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease susceptibility loci

We undertook a meta-analysis of six Crohns disease genome-wide association studies (GWAS) comprising 6,333 affected individuals (cases) and 15,056 controls and followed up the top association signals in 15,694 cases, 14,026 controls and 414 parent-offspring trios. We identified 30 new susceptibility loci meeting genome-wide significance (P < 5 × 10−8). A series of in silico analyses highlighted particular genes within these loci and, together with manual curation, implicated functionally interesting candidate genes including SMAD3, ERAP2, IL10, IL2RA, TYK2, FUT2, DNMT3A, DENND1B, BACH2 and TAGAP. Combined with previously confirmed loci, these results identify 71 distinct loci with genome-wide significant evidence for association with Crohns disease.

Fecal calprotectin correlates more closely with the Simple Endoscopic Score for Crohn's disease (SES-CD) than CRP, blood leukocytes, and the CDAI

OBJECTIVES:Studies evaluating the correlation between the widely used Simple Endoscopic Score for Crohns disease (SES-CD) and noninvasive markers are scarce. The aim of this study was to evaluate the correlation between the SES-CD and fecal calprotectin, C-reactive protein (CRP), blood leukocytes, and the Crohns disease activity index (CDAI).METHODS:Crohns disease patients undergoing complete ileocolonoscopy were prospectively enrolled and scored independently according to the SES-CD and the CDAI. SES-CD was defined as follows: inactive 0–3; mild 4–10; moderate 11–19; and high ≥20.RESULTS:Values in CD patients (n=140 ileocolonoscopies) compared with controls (n=43) are as follows: calprotectin, 334±322 vs. 18±5 μg/g; CRP, 26±29 vs. 3±2 mg/l; and blood leukocytes, 9.1±3.4 vs. 5.4±1.9 g/l (all P<0.001). The SES-CD correlated closest with calprotectin (Spearmans rank correlation coefficient r=0.75), followed by CRP (r=0.53), blood leukocytes (r=0.42), and the CDAI (r=0.38). Calprotectin was the only marker that could discriminate inactive endoscopic disease from mild activity (104±138 vs. 231±244 μg/g, P<0.001), mild from moderate activity (231±244 vs. 395±256 μg/g, P=0.008), and moderate from high activity (395±256 vs. 718±320 μg/g, P<0.001). The overall accuracy for the detection of endoscopically active disease was 87% for calprotectin (cutoff 70 μg/g), 66% for elevated CRP, 54% for blood leukocytosis, and 40% for the CDAI ≥150.CONCLUSIONS:Fecal calprotectin correlated closest with SES-CD, followed by CRP, blood leukocytes, and the CDAI. Furthermore, fecal calprotectin was the only marker that reliably discriminated inactive from mild, moderate, and highly active disease, which underlines its usefulness for activity monitoring.

Discriminating IBD from IBS: Comparison of the test performance of fecal markers, blood leukocytes, CRP, and IBD antibodies†

Background: Symptoms of inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) can overlap. We aimed to determine the accuracy of fecal markers, C‐reactive protein (CRP), blood leukocytes, and antibody panels for discriminating IBD from IBS and to define a “best test.” Methods: We prospectively included 64 patients with IBD (36 Crohns disease [CD], 28 ulcerative colitis [UC]), 30 with IBS, and 42 healthy controls. Besides CRP and blood leukocytes, blinded fecal samples were measured for calprotectin (PhiCal Test, enzyme‐linked immunosorbent assay [ELISA]), lactoferrin (IBD‐SCAN, ELISA), Hexagon‐OBTI (immunochromatographic test for detection of human hemoglobin), and LEUKO‐TEST (lactoferrin latex‐agglutination test). Blinded serum samples were measured for the antibodies ASCA (ELISA) and pANCA (immunofluorescence). Results: Overall accuracy of tests for discriminating IBD from IBS: IBD‐SCAN 90%, PhiCal Test 89%, LEUKO‐TEST 78%, Hexagon‐OBTI 74%, CRP 73%, blood leukocytes 63%, CD antibodies (ASCA+/pANCA− or ASCA+/pANCA+) 55%, UC antibodies (pANCA+/ASCA−) 49%. ASCA and pANCA had an accuracy of 78% for detecting CD and 75% for detecting UC, respectively. The overall accuracy of IBD‐SCAN and PhiCal Test combined with ASCA/pANCA for discriminating IBD from IBS was 92% and 91%, respectively. Conclusions: The PhiCal Test and IBD‐SCAN are highly accurate for discriminating IBD from IBS. There is only marginal additional diagnostic accuracy when the PhiCal Test and IBD‐SCAN are combined with ASCA and pANCA. ASCA and pANCA have a high specificity for IBD.

Ulcerative colitis : correlation of the Rachmilewitz endoscopic activity index with fecal calprotectin, clinical activity, C-reactive protein, and blood leukocytes

Background: The accuracy of noninvasive markers for the detection of endoscopically active ulcerative colitis (UC) according the Rachmilewitz Score is so far unknown. The aim was to evaluate the correlation between endoscopic disease activity and fecal calprotectin, Clinical Activity Index, C‐reactive protein (CRP), and blood leukocytes. Methods: UC patients undergoing colonoscopy were prospectively enrolled and scored independently according the endoscopic and clinical part of the Rachmilewitz Index. Patients and controls provided fecal and blood samples for measuring calprotectin, CRP, and leukocytes. Results: Values in UC patients (n = 134) compared to controls (n = 48): calprotectin: 396 ± 351 versus 18.1 ± 5 μg/g, CRP 16 ± 13 versus 3 ± 2 mg/L, blood leukocytes 9.9 ± 3.5 versus 5.4 ± 1.9 g/L (all P < 0.001). Endoscopic disease activity correlated closest with calprotectin (Spearmans rank correlation coefficient r = 0.834), followed by Clinical Activity Index (r = 0.672), CRP (r = 0.503), and leukocytes (r = 0.461). Calprotectin levels were significantly lower in UC patients with inactive disease (endoscopic score 0‐3, calprotectin 42 ± 38 μg/g), compared to patients with mild (score 4‐6, calprotectin 210 ± 121 μg/g, P < 0.001), moderate (score 7‐9, calprotectin 392 ± 246 μg/g, P = 0.002), and severe disease (score 10‐12, calprotectin 730 ± 291 μg/g, P < 0.001). The overall accuracy for the detection of endoscopically active disease (score ≥4) was 89% for calprotectin, 73% for Clinical Activity Index, 62% for elevated CRP, and 60% for leukocytosis. Conclusions: Fecal calprotectin correlated closest with endoscopic disease activity, followed by Clinical Activity Index, CRP, and blood leukocytes. Furthermore, fecal calprotectin was the only marker that reliably discriminated inactive from mild, moderate, and highly active disease, which emphasizes its usefulness for activity monitoring. Inflamm Bowel Dis 2009

Evaluation of serologic disease markers in a population-based cohort of patients with ulcerative colitis and Crohn's disease.

BackgroundThe sensitivity of assays for antineutrophil cytoplasmic antibody (ANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and antipancreatic antibody (PAB) in different laboratories is unknown. Likewise, the sensitivity and diagnostic usefulness of these assays in patients with inflammatory bowel disease (IBD) in the community is unknown. MethodsAn incidence cohort of 290 patients with IBD were offered participation in the study. Blood was obtained from 162 patients (56%) (83 with ulcerative colitis, 79 with Crohns disease) who agreed to participate. ANCA was determined in five laboratories, ASCA in two laboratories, and PAB in one laboratory. ResultsIn ulcerative colitis, the sensitivity of ANCA determined in five laboratories varied widely, ranging from 0–63%. In Crohns disease, the sensitivity of ASCA determined in two laboratories did not vary significantly, ranging from 39–44%; and the sensitivity of PAB determined in one laboratory was 15%. The optimal diagnostic usefulness was obtained from one laboratory where the positive predictive values of a positive ANCA assay combined with a negative ASCA assay for ulcerative colitis, and a negative ANCA combined with a positive ASCA for Crohns disease, were 75% and 86%, respectively. ConclusionsIn patients with IBD, the sensitivity of ANCA varied widely in different laboratories, whereas the prevalence of ASCA was similar. The positive predictive values of the ANCA assay combined with the ASCA assay for ulcerative colitis and Crohns disease are high enough to be clinically useful.

Comparison of interferon-gamma release assay versus tuberculin skin test for tuberculosis screening in inflammatory bowel disease

OBJECTIVES: Reactivation of latent tuberculosis (TB) in inflammatory bowel disease (IBD) patients treated with antitumor necrosis factor-alpha medication is a serious problem. Currently, TB screening includes chest x-rays and a tuberculin skin test (TST). The interferon-gamma release assay (IGRA) QuantiFERON-TB Gold In-Tube (QFT-G-IT) shows better specificity for diagnosing TB than the skin test. This study evaluates the two test methods among IBD patients.METHODS: Both TST and IGRA were performed on 212 subjects (114 Crohns disease, 44 ulcerative colitis, 10 indeterminate colitis, 44 controls).RESULTS: Eighty-one percent of IBD patients were under immunosuppressive therapy; 71% of all subjects were vaccinated with Bacille Calmette Guérin; 18% of IBD patients and 43% of controls tested positive with the skin test (P < 0.0001). Vaccinated controls tested positive more often with the skin test (52%) than did vaccinated IBD patients (23%) (P= 0.011). Significantly fewer immunosuppressed patients tested positive with the skin test than did patients not receiving therapy (P= 0.007); 8% of patients tested positive with the QFT-G-IT test (14/168) compared to 9% (4/44) of controls. Test agreement was significantly higher in the controls (P= 0.044) compared to the IBD group.CONCLUSIONS: Agreement between the two test methods is poor in IBD patients. In contrast to the QFT-G-IT test, the TST is negatively influenced by immunosuppressive medication and vaccination status, and should thus be replaced by the IGRA for TB screening in immunosuppressed patients having IBD.

Antibodies to flagellin indicate reactivity to bacterial antigens in IBS patients

Abstract  One of the several possible causes of irritable bowel syndrome (IBS) is thought to be low‐grade mucosal inflammation. Flagellin, the primary structural component of bacterial flagellae, was shown in inflammatory bowel disease patients to activate the innate and adaptive immunity. It has not yet been conclusively established if IBS patients show reactivity to luminal antigens. In 266 patients [112 IBS, 61 Crohn’s disease (CD), 50 ulcerative colitis (UC) and 43 healthy controls (HC)], we measured antibodies to flagellin (FAB, types A4‐Fla2 and Fla‐X), anti‐Saccharomyces cerevisiae antibodies (ASCA) (both ELISA), antipancreas antibodies (PAB) and perinuclear antineutrophil cytoplasmatic antibodies (p‐ANCA) (both IF). All IBS patients had normal fecal calprotectin (mean 21 μg mL−1, SD 6.6) and fulfilled the ROME II criteria. Frequencies of antibodies in patients with IBS, CD, UC and HC, respectively, are as follows (in per cent): antibodies against A4‐Fla2: 29/48/8/7; antibodies against Fla‐X: 26/52/10/7; ASCA: 6/59/0/2; p‐ANCA: 0/10/52/0; and PAB: 0/28/0/0. Antibodies against A4‐Fla2 and Fla‐X were significantly more frequent in IBS patients than in HC (P = 0.004 and P = 0.009). Antibodies to A4‐Fla2 and Fla‐X were significantly more frequent in IBS patients with antecedent gastroenteritis compared to non‐postinfectious IBS patients (P = 0.002 and P = 0.012). In contrast to ASCA, PAB and p‐ANCA, antibodies against A4‐Fla2 and Fla‐X were found significantly more often in IBS patients, particularly in those with postinfectious IBS, compared to HC. This observation supports the concept that immune reactivity to luminal antigens has a putative role in the development of IBS, at least in a subset of patients.

Resistin is an inflammatory marker of inflammatory bowel disease in humans.

Objectives Resistin, a recently discovered adipokine, has been shown to be associated with inflammatory conditions such as insulin resistance, obesity, atherosclerosis and rheumatoid arthritis. We therefore hypothesized that (i) resistin levels may be elevated in patients with inflammatory bowel disease (IBD) and (ii) resistin levels may be associated with disease activity in IBD. Methods We addressed these questions by testing for associations between resistin plasma levels, inflammatory parameters and clinical disease activity in a case–control study with 235 patients with Crohns disease (CD), 112 patients with ulcerative colitis (UC) and 144 healthy controls. Results Patients with IBD showed significantly higher resistin levels compared with controls (P<0.0001). In both, patients with CD and UC, resistin concentrations were significantly associated with elevated white blood cell count (P<0.0001), C-reactive protein (CRP) (P<0.0001) and disease activity (P≤0.0001). In multivariate logistic regression analysis, resistin levels were identified as an independent predictor of active disease (odds ratio 1.014, 95% confidence interval 1.002–1.027, P=0.02) in patients with CD after adjusting for sex, age, body mass index, white blood cell count and CRP. In UC patients, resistin was associated with active disease in multivariate regression analysis after control for sex, age, body mass index and white blood cell count (odds ratio 1.015, 95% confidence interval 1.002–1.029, P=0.02). Addition of CRP, however, abolished this association. Conclusion Resistin levels are an independent predictor of disease activity in patients with CD. Resistin may represent a novel link between inflammation and IBD.

Accuracy of Four Fecal Assays in the Diagnosis of Colitis

PurposeThis study was designed to evaluate the accuracy of four different fecal markers in discriminating between irritable bowel syndrome, inflammatory bowel disease, and other forms of colitis and to examine the feasibility of collecting fecal samples in outpatients.MethodsWe prospectively included 20 patients with irritable bowel syndrome, 36 with inflammatory bowel disease (24 Crohn’s disease, 12 ulcerative colitis), and 18 with other forms of colitis (8 infectious colitis, 5 ischemic colitis, 5 medication-induced colitis). Diagnosis was established by clinical, laboratory, and endoscopic workup. Blinded fecal samples were measured for calprotectin (PhiCal™-Test, ELISA), lactoferrin (IBD-SCAN™, ELISA), Hexagon OBTI (immunochromatographic test for detection of human hemoglobin), and LEUKO-TEST (lactoferrin latex-agglutination test).ResultsOverall accuracy for discriminating irritable bowel syndrome from inflammatory bowel disease or other forms of colitis was recorded, respectively: IBD-SCAN™ 91/100 percent, PhiCal™-Test 89/100 percent, LEUKO-TEST 83/89 percent, Hexagon OBTI 77/84 percent, C-reactive protein 71/79 percent, and blood leukocytes 63/68 percent. Differentiation of inflammatory bowel disease from other forms of colitis with fecal markers was as follows: range of overall accuracy from 43 to 50 percent. Overall accuracy (in percent) for discrimination of irritable bowel syndrome from patients with Crohn’s disease in remission (CDAI<150) was: IBD-SCAN™ 90, PhiCal™-Test 90, LEUKO-TEST 85, Hexagon OBTI 77. Calprotectin and lactoferrin were significantly elevated in patients with Crohn’s disease with CDAI>150 compared with those in remission. Fecal sampling feasibility in outpatients was high (acceptance rate 95 percent).ConclusionsIBD-SCAN™ and PhiCal™-Test have the best overall accuracy for detection of colitis, followed by LEUKO-TEST, Hexagon OBTI, C-reactive protein, and blood leukocytes. Accuracy of fecal markers is high even in patients with Crohn’s disease in remission. Fecal sampling feasibility was high in outpatients. Because fecal markers are unspecific, endoscopic workup remains crucial to determine the underlying cause of colitis.

Complementary alternative medicine in patients with inflammatory bowel disease: use and attitudes.

Background: A widespread increase in the use of complementary alternative medicine (CAM) by patients with inflammatory bowel disease (IBD) has been recognized. The aim of our study was to evaluate both the extent and the determinants of CAM use by outpatients with IBD. Methods: Outpatients of the IBD centre at the University Hospital of Berne and patients of two gastroenterology private practices in Olten (Switzerland) completed a mailed self-administrated questionnaire regarding alternative medicine. The questionnaire addressed the following topics: demographic variables; disease-related data; the use of 16 types of complementary medicine; comparison between attitudes towards alternative versus conventional medicine and out-of pocket expenses. Results: Alternative medicine has been used by 47% of the patients. Diagnosis, duration and activity of disease, gender, age, previous surgery were not predictive for the use of CAM. The most commonly used CAM methods were: homeopathy, acupuncture and traditional Chinese medicine. Reasons cited for the use of CAM were: lack of satisfaction with and side effects of conventional therapy and the perceived safety of CAM. Sixty-one percent of patients noted that their IBD had improved with the use of CAM. By contrast, 16% noted a flare during CAM therapies. Forty-seven percent of patients paid more than €400 per year for CAM. Conclusions: Complementary medicine use is common in patients with IBD. Frequently cited reasons for the use of complementary therapies were safety of CAM; dissatisfaction with conventional therapies, including their side effects; and that CAM can be used in addition to conventional therapy.