Jutta Weber

Spatial organization and composition of the mucosal flora in patients with inflammatory bowel disease.

ABSTRACT The composition and spatial organization of the mucosal flora in biopsy specimens from patients with inflammatory bowel disease (IBD; either Crohns disease or ulcerative colitis), self-limiting colitis, irritable-bowel syndrome (IBS), and healthy controls were investigated by using a broad range of fluorescent bacterial group-specific rRNA-targeted oligonucleotide probes. Each group included 20 subjects. Ten patients who had IBD and who were being treated with antibiotics were also studied. Use of nonaqueous Carnoy fixative to preserve the mucus layer was crucial for detection of bacteria adherent to the mucosal surface (mucosal bacteria). No biofilm was detectable in formalin-fixed biopsy specimens. Mucosal bacteria were found at concentrations greater than 109/ml in 90 to 95% of IBD patients, 95% of patients with self-limiting colitis, 65% of IBS patients, and 35% of healthy controls. The mean density of the mucosal biofilm was 2 powers higher in IBD patients than in patients with IBS or controls, and bacteria were mostly adherent. Bacteroides fragilis was responsible for >60% of the biofilm mass in patients with IBD but for only 30% of the biofilm mass in patients with self-limiting colitis and <15% of the biofilm mass in patients with IBS. In contrast, bacteria which positively hybridized with the probe specific for Eubacterium rectale-Clostridium coccoides accounted for >40% of the biofilm in IBS patients but for <15% of the biofilm in IBD patients. In patients treated with (5-ASA) or antibiotics, the biofilm could be detected with 4,6-diamidino-2-phenylindole but did not hybridize with fluorescence in situ hybridization probes. A Bacteroides fragilis biofilm is the main feature of IBD. This was not previously recognized due to a lack of appropriate tissue fixation. Both 5-ASA and antibiotics suppress but do not eliminate the adherent biofilm.

Association between intraepithelial Escherichia coli and colorectal cancer

BACKGROUND & AIMS Although multiple studies have focused on Helicobacter pylori, little is known about the mucosa-associated flora of the colon. The aim of this study was to detect bacteria directly in colonic mucosa from patients screened for colorectal cancer. METHODS Bacteria were quantified with the polymerase chain reaction and identified by comparative sequence analysis in colonoscopic biopsy specimens from 31 asymptomatic and 34 symptomatic controls with normal colonoscopic findings, 29 patients with colonic adenoma, and 31 patients with colorectal carcinoma. In 41 patients, intra- and extracellular location of bacteria was confirmed with the gentamicin protection assay. RESULTS No bacteria were detected in biopsy specimens from 97% of asymptomatic and 69% of symptomatic controls. In contrast, bacterial concentrations of 10(3)-10(5) colony-forming units per microliter were detected in biopsy specimens from both malignant and macroscopically normal tissue in 90% and 93% of patients with adenoma and carcinoma, respectively. E. coli and coli-like bacteria were shown to colonize the colonic mucosa in 82% of these patients. The gentamicin protection assay indicated that E. coli was partially intracellular in 87% of patients with adenoma and carcinoma and in none of the controls. CONCLUSIONS The colonic mucosa of patients with colorectal carcinoma but not normal colonic mucosa is colonized by intracellular E. coli.

Evaluation of Criteria for the Activity of Crohn’s Disease by Power Doppler Sonography

Background/Aim: In recent years, power Doppler sonography has been proposed as a method to assess disease activity in patients with Crohn’s disease. The aim of this prospective study was to evaluate diagnostic criteria for power Doppler sonography by blinded comparison with ileocolonoscopy. Methods: Twenty-two patients with confirmed Crohn’s disease were prospectively investigated with B-mode and power Doppler sonography (HDI 5000, Philips Ultrasound) as well as ileocolonoscopy. Sonography was performed within 3 days before endoscopy. All procedures were performed by experienced examiners who were blinded to the clinical data and other results. Defined ultrasound parameters (bowel wall thickness, vascularization pattern) were used to determine a sonographic score of the activity. The degree of activity was scored from 1 (none) to 4 (high) by both ultrasound and ileocolonoscopy (pattern, extent of typical lesions). For each patient all segments of the colon and the terminal ileum were evaluated by both ultrasound and endoscopy. The weighted ĸ test was used (StatXact software) for statistical analysis. Results: In total, 126 bowel segments were evaluated by both ultrasound and endoscopy. The study showed a high concordance of power Doppler sonography and ileocolonoscopy (weighted ĸ by region: sigmoid colon: 0.81; transverse colon: 0.78; ascending colon: 0.75; cecum: 0.84; terminal ileum: 0.82). Highest concordance was found in the descending colon (weighted ĸ: 0.91; 95% CI: 0.83–0.98). Conclusions: Combination of B-mode and power Doppler sonography has a high accuracy in the determination of disease activity in Crohn’s disease when compared to ileocolonoscopy. The diagnostic criteria established in this study can be useful for the evaluation of inflammatory bowel diseases by ultrasound.

Endoscopic injection of mitomycin adsorbed on activated carbon particles versus brachytherapy for advanced esophageal cancer

Background: In a pilot study we could show that local injections of mitomycin adsorbed on activated carbon particles (MMCCH) therapy is an effective, well tolerated treatment for non-resectable esophageal tumors. The Aim of this study is to compare brachytherapy (RTL) and endoluminal MMCCH in nonresectable esophageal carcinomas. Methods: Twelve patients with non-resectable esophageal carcinoma (7stage IV, 5 stage III; 5 suprabifurcal, 7 infrabifurcal) were randomized to RTL and recieved four weekly 5 Gy with a bougie applicator using a t92 iridium source, resulting in 20 Gy. Fifteen patients (12 stage IV, 3 stage III; 8 suprabifurcal, 7 infrabifurcal) were randomized to four weekly injections of 15 mg MM CH via a 5 mm sclerotherapy needle into the endoscopically visualized tumor, resulting in a total dose of 60 mg. In both groups (6 RTL group, 10 MMC-CH group) metal stents were implanted additionally before therapy if the lumen was obstructed and there was enough distance to the upper sphincter (lcm). Primary outcome parameter was time to local tumor progress, secondary parameters were dysphagia, Quality of Life (Karnofsky index) and survival time. Tumor staging (CT chest, endosonography, gastroscopy, esophagogramm), symptom scores, life quality index (Spitzer index), were performed before and every other month after therapy. Results: Median time (weeks) to local tumor progress was 19.62 +_ 19.13 in the RTL group and 11.63 +7.99 in the MMC CH group (n.s.). Dysphagia score and Karnofsky-index improved in both groups, life quality index only in the MMC-CH group (Fig.). Esophagitis occured in 9/11 patients (81.8%) in the RTL group (mean 1.27 ± 0.9 grade) and fever and cyanosis during injection in 1/15 patients (6.6%) in the MMC-CH group.