Hengameh Mirsepasi

A phylogenetic group of Escherichia coli associated with active left-sided Inflammatory Bowel Disease

BackgroundEscherichia coli have been found in increased numbers in tissues from patients with Inflammatory Bowel Disease (IBD) and adherent-invasive E. coli have been found in resected ileum from patients with Crohns disesae. This study aimed to characterize possible differences in phylogenetic group (triplex PCR), extraintestinal pathogenic E. coli (ExPEC) genes and multilocus sequence type (MLST) between E. coli strains isolated from IBD patients with past or present involvement of the left side of the colon and from controls.ResultsFecal samples were collected from 18 patients and from 10 healthy controls. Disease activity was evaluated by sigmoidoscopy. Interestingly, E. coli strains of the phylogenetic group B2 were cultured from 60% of patients with IBD compared to 11% of healthy controls (p < 0.05). Furthermore, when comparing the number of E. coli B2 strains with at least one positive ExPEC gene among different groups, 86% were found positive among active IBD patients, significantly more than 13% among inactive IBD patients (p < 0.05), and 11% among healthy controls (p < 0.05). The B2 phylogenetic group was found in a specific cluster based on MLST, but no further separation between E. coli strains associated with active compared to inactive IBD was achieved.ConclusionIn conclusion, E. coli of the phylogenetic group B2 were isolated more frequently from IBD patients with past or present involvement of the left side of the colon compared to healthy controls, and B2 strains with ExPEC genes were found more frequently among IBD patients with active disease compared to patients with inactive disease.

Active ulcerative colitis associated with low prevalence of Blastocystis and Dientamoeba fragilis infection

Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark, Department of Gastroenterology, Hvidovre University Hospital, Copenhagen, Denmark, Department of Clinical Microbiology, Slagelse Hospital, Slagelse, Denmark, Department of Clinical Microbiology, Hvidovre University Hospital, Copenhagen, Denmark, and National Food Institute, Technical University of Denmark, Copenhagen, Denmark

Ciprofloxacin and probiotic Escherichia coli Nissle add-on treatment in active ulcerative colitis: A double-blind randomized placebo controlled clinical trial

BACKGROUND AND AIM Ulcerative colitis (UC) is a chronic inflammatory bowel disease. The probiotic bacterium Escherichia coli Nissle 1917 (EcN) has been used to maintain and induce clinical remission in UC. Our aim was to test the effect of Ciprofloxacin and/or orally administered EcN as add-on to conventional therapies in patients with active UC. PATIENTS AND METHODS Our single center double-blinded randomized placebo controlled study included patients with a Colitis Activity Index (CAI) score of at least 6. Patients were randomized to Ciprofloxacin or placebo for 1week followed by EcN or placebo for 7weeks. All 4 treatments were given as add-on treatments. RESULTS One hundred subjects with active UC were recruited. In the per-protocol analysis we, surprisingly, found that in the group receiving placebo/EcN fewer patients, 54%, reached remission compared to the group receiving placebo/placebo, 89%, p<0.05. Among patients treated with Cipro/placebo and Cipro/EcN, 78% and 66% reached remission, respectively. Furthermore, the group receiving placebo/EcN had the largest number of withdrawals, 11 of 25 (44%), compared to 15 of 75 (20%) in any of the other groups, p<0.05. Indication of lack of mucosal healing was found in the group treated with placebo/Nissle, since only 4 (29%) of the 14 patients, who completed the study, reported no blood in stools at week 12 (p<0.02), compared to 63%, 67% and 65% in groups treated with Cipro/Nissle, Cipro/placebo and placebo/placebo, respectively. CONCLUSIONS Our data suggest that there is no benefit in the use of E. coli Nissle as an add-on treatment to conventional therapies for active ulcerative colitis. Furthermore, treatment with E. coli Nissle without a previous antibiotic cure resulted in fewer patients reaching clinical remission.

Investigation of the early intestinal microflora in premature infants with/without necrotizing enterocolitis using two different methods

Introduction:The pathophysiology of necrotizing enterocolitis (NEC) is multifactorial, and gastrointestinal bacteria are thought to play an important role. In this study, the role of microflora in the gastrointestinal tract of neonates with NEC was assessed by comparing cases with controls.Results:Of the 163 neonates, 21 developed NEC. The risk of NEC decreased by 8% with each additional day of gestational age.Discussion:Typically, very few bacterial species could be cultured from the fecal specimens obtained. Gram-positive (G+) bacteria dominated the samples in the NEC group, whereas in the control group mixed flora of G+ and Gram-negative (G−) bacteria were isolated. Surprisingly, molecular analysis using PCR-DGGE profiles did not confirm these differences. Our data suggest that G+ bacteria in the intestine may play a role in the development of NEC in premature infants.Methods:One hundred and sixty three neonates born at <30 weeks of gestation were enrolled. Fecal samples taken during the first month of life were subjected to culture and PCR-denaturing gradient gel electrophoresis (PCR-DGGE). A total of 482 fecal samples were examined.

Microbial diversity in fecal samples depends on DNA extraction method: easyMag DNA extraction compared to QIAamp DNA stool mini kit extraction

BackgroundThere are challenges, when extracting bacterial DNA from specimens for molecular diagnostics, since fecal samples also contain DNA from human cells and many different substances derived from food, cell residues and medication that can inhibit downstream PCR. The purpose of the study was to evaluate two different DNA extraction methods in order to choose the most efficient method for studying intestinal bacterial diversity using Denaturing Gradient Gel Electrophoresis (DGGE).FindingsIn this study, a semi-automatic DNA extraction system (easyMag®, BioMérieux, Marcy I’Etoile, France) and a manual one (QIAamp DNA Stool Mini Kit, Qiagen, Hilden, Germany) were tested on stool samples collected from 3 patients with Inflammatory Bowel disease (IBD) and 5 healthy individuals.DNA extracts obtained by the QIAamp DNA Stool Mini Kit yield a higher amount of DNA compared to DNA extracts obtained by easyMag® from the same fecal samples. Furthermore, DNA extracts obtained using easyMag® seemed to contain inhibitory compounds, since in order to perform a successful PCR-analysis, the sample should be diluted at least 10 times. DGGE performed on PCR from DNA extracted by QIAamp DNA Stool Mini Kit DNA was very successful.ConclusionQIAamp DNA Stool Mini Kit DNA extracts are optimal for DGGE runs and this extraction method yields a higher amount of DNA compared to easyMag®.

Seroreactivity to E. coli outer membrane protein C antibodies in active inflammatory bowel disease; diagnostic value and correlation with phylogroup B2 E. coli infection

Abstract Background. Several serologic tests, including anti-outer membrane porin C antibody (Omp C), are used for screening and as marker of disease course in inflammatory bowel diseases (IBD). Our aim was to investigate possible differences in Omp C level in patients with active and inactive IBD compared to controls. Methods. All blood samples were tested for Omp C. Disease activity was evaluated by Harvey Bradshaw Index, Simple Clinical Activity Index and Modified Pouchitis Disease Activity Index. Results. Blood samples were collected from 113 patients and 60 controls. Patients with active IBD did not have a higher level of Omp C than patients in remission. Surprisingly, in patients with active Crohns disease a significantly lower level of Omp C was found compared with patients with inactive Crohns disease (p < 0.05). All other groups among patients with IBD did have a significantly higher level of Omp C, compared with controls, including patients with acute gastroenteritis (p < 0.05). Although IBD patients with phylogroup B2 E. coli cultured from their fecal samples, were more likely to have a positive Omp C test (p < 0.05), this could not explain the low Omp C level in the subgroup of patients with active Crohns disease. Conclusions. Omp C titer was not raised in patients with active IBD compared with patients in remission. In addition, there was no difference in Omp C level in patients with active Crohns disease compared with controls. These observations do not support the use of Omp C serology testing, either in disease activity assessment, or in screening for active Crohns disease.

E. coli Outer Membrane Protein C Antibodies in Active and Inactive Inflammatory Bowel Diseases

G A A b st ra ct s detection of D. fragilis was higher in inactive UC than among controls (12 %), this difference was, however, not statistically significant. No difference in the detection of D. fragilis was found in active vs. inactive CD or IPAA. Conclusion: In conclusion, Blastocystis and D. fragilis were isolated more frequently from patients with inactive ulcerative colitis compared to patients with active ulcerative colitis. No similar differences were seen among patients with Crohns disease or an ileal pouch anal anastomosis. A possible protective role of these parasitic infections in ulcerative colitis could be speculated.