Stephan Brackmann

A characterization in childhood inflammatory bowel disease, a new population-based inception cohort from South-Eastern Norway, 2005–07, showing increased incidence in Crohn's disease

Objective. Owing to rising incidence rates in inflammatory bowel disease (IBD), there has been increased interest in causal relationships in pediatric disease. The present population-based inception cohort was recruited in the Oslo area from 2005 to 2007, with the aim of conducting a detailed characterization of treatment-naïve patients at diagnosis. Material and methods. After an invitation was extended to all general practitioners in the catchment area, patients aged <18 years with suspected IBD were diagnosed by proximal and distal endoscopy, MRI, demographic, clinical, and histological and molecular characteristics. Symptomatic non-IBD patients served as controls. Results. Of 100 pediatric patients, 62 had IBD (39 Crohns disease (CD), 19 ulcerative colitis (UC), 4 IBD unclassified (IBDU)) and 38 other diseases. Median age at diagnosis for IBD was 13.1 years (56.4% males), median symptom duration 6 months, and 69% L3 (Vienna classification). With 195,000 children aged <18 years in the catchment area, the incidence rate of IBD per 100,000/years inhabitants was 10.9 (6.8 for CD, 3.6 for UC, and 0.6 IBDU) and for those aged <16 years (178,500) the incidence rate was 10.6. The higher NOD2 allele frequency among children may partly contribute to the increase. Conclusions. The results indicate a marked rise in the incidence of CD in contrast to no increase in UC in South-Eastern Norway, compared with the figures from the last 15 years. Time from onset of symptoms to diagnosis still represents a challenge for early characterization in IBD.

Evaluation of disease activity in IBD at the time of diagnosis by the use of clinical, biochemical, and fecal markers

Abstract Objective. The present population based adult cohort was part of a new prospective study of patients with inflammatory bowel disease (IBD) in South-Eastern Norway, the Inflammatory Bowel South-Eastern Norway II study, investigating disease characteristics in an attempt to improve our knowledge regarding factors related to early clinical phenotype and disease activity. Material and methods. Patients suspected to have IBD on the basis of predefined symptoms, including abdominal pain, diarrhea, and/or blood in stool for more than 10 days were examined at the local hospital. Colonoscopy with biopsies was performed and blood and stool samples were taken. Results. In ulcerative colitis (UC) patients, the median Simple Clinical Colitis Activity Index (SCCAI) was 4 (range 0–10) in mild and 6 (range 0–14) in patients with moderate or severe endoscopic activity of inflammation (p = 0.002). The calprotectin concentration in feces was significantly related to the SCCAI (p = 0.034) and the Mayo endoscopic subscore (p = 0.031). There was a significant association between the C-reactive protein (CRP) value, leucocytes and thrombocytes and the SCCAI, but only leucocytes were significantly associated with the Mayo endoscopic subscore. In Crohns disease (CD) patients, there was no statistical significant association between the Harvey-Bradshaw Index (HBI) and the endoscopic grade of mucosal inflammation (p = 0.8). The calprotectin concentration in feces was significantly related to the endoscopic activity score (p = 0.004), but not to the HBI (p = 0.5). HBI was significantly related to the CRP value (p = 0.047) and thrombocytes (p = 0.03). Conclusions . In UC, both biochemical and fecal markers are related to disease activity and extent of disease, whereas in CD, the fecal calprotectin concentration is a reliable marker of mucosal affection, but not for systemic disease activity.

Relationship between clinical parameters and the colitis-colorectal cancer interval in a cohort of patients with colorectal cancer in inflammatory bowel disease.

Objective. Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC), but more knowledge is needed about the possible relationship between clinical parameters and the time to development of cancer in IBD. The aim of the study was to determine the variability of the colitis-CRC interval and to analyze the association with clinical variables in an attempt to gain information on predictive factors of time to cancer within a relatively large cohort of CRC patients. Material and methods. Patients diagnosed with IBD prior to 1 May 2005 at three university hospitals in Oslo were matched against the CRC files at the Cancer Registry of Norway. Only histological re-confirmed IBD and adenocarcinoma of the colorectum were included. Results. Sixty-one patients with CRC in ulcerative colitis and 6 in Crohns disease, including 13 CRC in primary sclerosing cholangitis (PSC), covering a follow-up of 1625 patient years, were identified. The median time from diagnosis of IBD to CRC was 17 years. Seven of 58 patients (12%) developed CRC within 10 years from onset of IBD symptoms and 14/67 (21%) within 10 years after the diagnosis of IBD. The colitis-CRC interval decreased by a factor of 0.154 (p=0.018) when age at onset of IBD increased by one year. Mean age at onset of IBD was 30 years in patients with Dukes’ stage C or D compared with 20 years in Dukes’ stage A or B patients (p=0.017). The colitis-CRC interval decreased by a factor of 0.138 (p=0.003) when the percentage of the colitis-CRC interval with active symptoms increased by 1%. Patients with PSC were significantly younger at onset of IBD symptoms (+PSC: 19 years versus no PSC:29 years, p=0.04), but the colitis-CRC interval was similar to IBD without PSC (17 years versus 20 years, p=0.236). Mean duration of the colitis-CRC interval was not related to family history or drug consumption prior to CRC. Conclusions. In the present cohort, for whom the median time from diagnosis of IBD to CRC was 17 years, 21% of the cancers developed before 10 years of disease, which is before colonoscopic screening is usually recommended. High age at onset of IBD may be related to a more aggressive development of CRC in IBD and early inclusion in screening programs might be considered for this group of patients. Symptom activity but not the diagnosis of PSC, family history of CRC or IBD or drug treatment seems to have an effect on the colitis-CRC interval.

Two distinct groups of colorectal cancer in inflammatory bowel disease.

Background: The histological variability in colitis‐associated colorectal cancer (CRC in inflammatory bowel disease [IBD]) and the association to clinical factors is unknown. Methods: In population‐based material including 67 patients with CRC in IBD, histopathology of the cancers and tissue samples from different colorectal localizations were reevaluated, and relationships to clinical factors analyzed. Results: Forty‐three of 60 patients (75%) showed dysplasia in the colorectum apart from the cancer, while 17 (25%) had no dysplasia at cancer diagnosis. Mean age at onset of IBD was 22 years in patients with and 34 years in patients without dysplasia (P = 0.01). The mean duration of colitis‐CRC interval was 21 years in patients with and 16 years in patients without dysplasia (P = 0.02). The latter group included all patients with a colitis‐CRC interval <10 years. Active inflammation was more likely to occur in patients with dysplasia (odds ratio [OR] 4.2). The 2 groups were not discriminated by gender, family history of CRC or IBD, diagnosis of PSC, medical treatment, active symptoms, or histological features like type of cancer and differentiation. In multiple logistic regression analysis the age at onset of IBD was the strongest predictive variable for dysplasia at cancer diagnosis (P = 0.025). Conclusions: Widespread neoplasia occurs in the majority of cases with CRC in IBD and is associated with early onset of IBD. Localized neoplasia occurs in about a quarter of the patients and shows an association with late‐onset IBD. The 2 groups probably represent different pathogenetic entities of neoplasia in IBD. This might have consequences for surveillance strategies.

Dominant Fecal Microbiota in Newly Diagnosed Untreated Inflammatory Bowel Disease Patients

Our knowledge about the microbiota associated with the onset of IBD is limited. The aim of our study was to investigate the correlation between IBD and the fecal microbiota for early diagnosed untreated patients. The fecal samples used were a part of the Inflammatory Bowel South-Eastern Norway II (IBSEN II) study and were collected from CD patients (n = 30), UC patients (n = 33), unclassified IBD (IBDU) patients (n = 3), and from a control group (n = 34). The bacteria associated with the fecal samples were analyzed using a direct 16S rRNA gene-sequencing approach combined with a multivariate curve resolution (MCR) analysis. In addition, a 16S rRNA gene clone library was prepared for the construction of bacteria-specific gene-targeted single nucleotide primer extension (SNuPE) probes. The MCR analysis resulted in the recovery of five pure components of the dominant bacteria present: Escherichia/Shigella, Faecalibacterium, Bacteroides, and two components of unclassified Clostridiales. Escherichia/Shigella was found to be significantly increased in CD patients compared to control subjects, and Faecalibacterium was found to be significantly reduced in CD patients compared to both UC patients and control subjects. Furthermore, a SNuPE probe specific for Escherichia/Shigella showed a significant overrepresentation of Escherichia/Shigella in CD patients compared to control subjects. In conclusion, samples from CD patients exhibited an increase in Escherichia/Shigella and a decrease in Faecalibacterium indicating that the onset of the disease is associated with an increase in proinflammatory and a decrease in anti-inflammatory bacteria.

Widespread but not localized neoplasia in inflammatory bowel disease worsens the prognosis of colorectal cancer

Background: Patients with inflammatory bowel disease (IBD) are at increased risk of colorectal cancer (CRC). Recently, new phenotypes of CRC in IBD have been suggested. Studies of the prognosis of CRC in IBD have shown conflicting results. The aim of the study was to analyze factors for prognosis in CRC‐IBD, including the impact of the new phenotypes. Methods: By using the nationwide, population‐based Cancer Registry of Norway, we compared survival of a CRC‐IBD cohort with CRC in the background population (all‐CRC), adjusting for the topographical distribution of dysplasia at cancer diagnosis (widespread versus localized neoplasia in IBD) and other factors. We also analyzed prognostic factors within CRC‐IBD. Results: The mean age at CRC diagnosis was 43 years in widespread, 52 years in localized neoplasia IBD, and 70 years in all‐CRC (P < 0.05). Adjusted for cofactors, prognosis of CRC‐IBD was poorer compared to all‐CRC (mortality rate ratio [MRR] 3.71, 95% confidence interval [CI]: 2.54–5.42, P < 0.001). Prognosis of widespread neoplasia IBD was poorer compared to all‐CRC (MRR 4.27, 95% CI: 2.83–6.44, P < 0.001) and compared to localized neoplasia IBD (MRR 3.58, 95% CI: 0.87–14.72, P = 0.076). Survival was not significantly different between localized neoplasia IBD and all‐CRC (P = 0.132). Conclusions: The results demonstrate lower age and poorer survival of CRC in IBD compared to CRC in the background population. The unfavorable effect of IBD on prognosis of CRC was pronounced in widespread neoplasia IBD. The diagnosis of this phenotype seems to be an important prognostic sign in patients with CRC in IBD. (Inflamm Bowel Dis 2010;)

Paucity of mycobacteria in mucosal bowel biopsies from adults and children with early inflammatory bowel disease

BACKGROUND The presence of Mycobacterium avium subspecies paratuberculosis (MAP) has previously been inferred in the genesis of Crohns disease (CD), and a higher incidence of MAP PCR positivity has been demonstrated in the gut and peripheral blood of CD patients than in healthy individuals. The objective of this prospective study was to assess the potential etiological role of MAP in the pathogenesis of CD. METHODS The presence of mycobacteria was assessed in bowel biopsies from newly diagnosed, treatment naïve Norwegian patients with IBD, including CD and ulcerative colitis (UC), as compared to a hospital-based cohort of CD and UC patients. Biopsies were collected from the small and large bowel in 354 individuals with suspected IBD. Detection of mycobacteria was performed by long-term cultivation in combination with direct detection by MAP IS900-specific PCR. RESULTS Among the specimens included from the patients with early IBD, samples from only two of the patients with CD (2.7%) and two of the non-IBD controls (1.5%) exhibited a positive growth signal. None of the CD patients and only one of the non-IBD controls was MAP PCR positive. Only the single PCR positive non-IBD control was also mycobacterial culture positive with Mycobacterium avium subsp. hominissuis. In the referral patients with long-term IBD, the prevalence of growth signal and MAP PCR positivity was higher (52 and 9%, respectively). CONCLUSIONS These findings demonstrate the paucity of MAP in the gut of treatment naïve CD patients. This study does not provide evidence for a role of MAP in early IBD.

The exon-level biomarker SLC39A14 has organ-confined cancer-specificity in colorectal cancer.

An alternative transcript variant of SLC39A14, caused by pre‐mRNA splicing, was recently suggested as a biomarker for colorectal cancer (CRC). In our study, we have validated the cancer‐specific splicing pattern of the mutually exclusive exons 4A and 4B in altogether 244 colorectal tissue samples. Exon‐specific quantitative RT‐PCR analyses across 136 Stage I–IV CRC samples and 44 normal colonic mucosa samples showed complete cancer‐specificity, as well as 94% sensitivity of SLC39A14‐exon4B relative to SLC39A14‐exon4A expression. However, across 20 samples from a range of healthy tissues, 18 expressed the CRC variant. This was true also for ten benign lymph nodes, demonstrating that the cancer‐specificity is mainly confined to the colon and rectum. Hence, clinical use of SLC39A14‐exon4B as a detection marker for CRC other than in samples taken from the bowel wall is diminished. Prognostic value by detection of metastasis to lymph nodes is also abated, elucidating an important pitfall to biomarker discovery. However, analyses of ten nondysplastic biopsies from patients with active inflammatory bowel disease showed negative results in seven samples and only weakly positive results in three samples, suggesting value of SLC39A14‐exon4B as a marker to distinguish CRC from other pathologic conditions of the colon. In conclusion, the SLC39A14‐exon4B transcript variant is a CRC biomarker with high sensitivity and organ‐confined specificity. Further use of the transcript and its encoded protein isoform should be explored in an organ‐confined context.

Age-Dependent Fecal Bacterial Correlation to Inflammatory Bowel Disease for Newly Diagnosed Untreated Children

The knowledge about correlation patterns between the fecal microbiota and inflammatory bowel diseases (IBD)—comprising the two subforms Crohns disease (CD) and ulcerative colitis (UC)—for newly diagnosed untreated children is limited. To address this knowledge gap, a selection of faecal specimens (CD, n = 27 and UC, n = 16) and non-IBD controls (n = 30) children (age < 18 years) was analysed utilising bacterial small subunit (SSU) rRNA. We found, surprising age dependence for the fecal microbiota correlating to IBD. The most pronounced patterns were that E. coli was positively (R 2 = 0.16, P = 0.05) and Bacteroidetes, negatively (R 2 = 0.15, P = 0.05) correlated to age for CD patients. For UC, we found an apparent opposite age-related disease correlation for both Bacteroides and Escherichia. In addition, there was an overrepresentation of Haemophilus for the UC children. From our, results we propose a model where the aetiology of IBD is related to an on-going immunological development in children requiring different age-dependent bacterial stimuli. The impact of our findings could be a better age stratification for understanding and treating IBD in children.

Analysis of DNA Methylation at Specific Loci in Stool Samples Detects Colorectal Cancer and High-Grade Dysplasia in Patients With Inflammatory Bowel Disease

BACKGROUND & AIMS: Patients with inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohns disease, are at increased risk for colorectal cancer (CRC). Analyses of DNA methylation patterns in stool samples have been reported to detect CRC in patients with IBD. We sought to validate these findings in larger cohorts and assess the accuracy of analysis of DNA methylation patterns in stool for detection of CRC and high‐grade dysplasia (HGD) normalized to methylation level at ZDHHC1. METHODS: We obtained buffered, frozen stool samples from a US case–control study and from 2 European surveillance cohorts (referral or population based) of patients with chronic ulcerative colitis (n = 248), Crohns disease (n = 82), indeterminate colitis (n = 2), or IBD with primary sclerosing cholangitis (n = 38). Stool samples were collected before bowel preparation for colonoscopy or at least 1 week after colonoscopy. Among the study samples, stools from individuals with IBD but without neoplasia were used as controls (n = 291). DNA was isolated from stool, exposed to bisulfite, and then assayed by multiplex quantitative allele‐specific real‐time target and signal amplification. We analyzed methylation levels of BMP3, NDRG4, VAV3, and SFMBT2 relative to the methylation level of ZDHHC1, and compared these between patients with CRC or HGD and controls. RESULTS: Levels of methylation at BMP3 and VAV3, relative to ZDHHC1 methylation, identified patients with CRC and HGD with an area under the curve value of 0.91 (95% CI, 0.77–1.00). Methylation levels at specific promotor regions of these genes identified 11 of the 12 patients with CRC and HGD, with 92% sensitivity (95% CI, 60%–100%) and 90% specificity (95% CI, 86%–93%). The proportion of false‐positive results did not differ significantly among the case–control, referral cohort, and population cohort studies (P = .60) when the 90% specificity cut‐off from the whole sample set was applied. CONCLUSIONS: In an analysis of stool samples from 3 independent studies of 332 patients with IBD, we associated levels of methylation at 2 genes (BMP3 and VAV3), relative to level of methylation at ZDHHC1, with detection of CRC and HGD. These methylation patterns identified patients with CRC and HGD with more than 90% specificity, and might be used in CRC surveillance.