Helicobacter Species in the Intestinal Mucosa of Patients with Ulcerative Colitis

Abstract

In a search for Helicobacter species in the intestinal mucosae of 42 patients with ulcerative colitis (UC) and 74 without UC, only H. pylori was found. Although the bacterium was detected in UC patients by culture (7.1%) and nested PCR (19.0%), its presence was not associated with the disease (P ‫؍‬ 0.13).Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) of unknown etiology that is confined to the large bowel mucosa. It seems to be a multifactorial disorder involving both genetic and environmental components, particularly the bacterial gut microbiota (13). However, no specific pathogenic or commensal bacterium has been convincingly implicated as the etiologic agent (4). Numerous studies have demonstrated that indigenous Helicobacter species of the gut of mice-Helicobacter hepaticus and Helicobacter bilis-are able to induce a persistent inflammation of the colon and cecum in some immunocompromised mouse models (1,5,8,15). Moreover, other Helicobacter species have been isolated from the gut of cottontop tamarins (14) and rhesus monkeys (7) with IBD-like disease. We hypothesize that species of the genus Helicobacter may also be associated with the pathogenesis of UC in human beings. Therefore, we investigated the presence of Helicobacter species in the intestinal mucosa of patients with UC and controls, by culture and PCR.We studied prospectively 42 patients with UC and 74 without IBD (controls) who were undergoing colonoscopy. Prior consent of all patients and approval of the institutional ethics committee were obtained. The UC diagnosis was established by standard clinic, radiologic, endoscopic, and histologic criteria. The extent of ulcerative colitis was determined by histology. The gastric H. pylori status was assessed by serology (Cobas-Core EIA; Roche Diagnostic Systems, Basel, Switzerland) (12) and 13 C urea breath test ( 13 C-UBT; NDIRIS; Wagner Analysen Technik, Bremen, Germany) (13). Patients' characteristics, including gastric H. pylori status, are shown in Table 1.Colonoscopic biopsy fragments were taken from the rectum, the sigmoid, descending, transverse, and ascending colon, the cecum, and the terminal ileum of each patient for culture and PCR. For culture, one fragment from each region was ground separately in a glass tissue grinder and plated onto Belo Horizonte medium (11) supplemented with polymyxin B plus bacitracin (Sigma Chemical Co., St. Louis, Mo.). The culture conditions and detailed characterization of the isolates were as previously described (10).DNA from bacteria and mucosal fragments was extracted with a QIAamp DNA minikit (Qiagen GmbH, Hilden, Germany).Primers C70 and B37 were used to amplify a product of ϳ1.5 kb from the 16S rRNA gene of the isolated strains (10). The amplicons were then purified and directly sequenced as described by Queiroz et al. (10). The sequences were aligned and compared with those in the GenBank database.For the detection of Helicobacter DNA in fragments of the intestinal mucosa, the 16S rRNA gene was amplified by nested PCR using an outer prime...

The role of microbial agents in the pathogenesis of inflammatory bowel disease

“…may contribute to the persistence of colonic inflammation. This finding was in line with Oliveira et al [49] who demonstrated that only H. pylori was found in mucosal sample from patients with ulcerative colitis.…”

The Family Helicobacteraceae

“…In addition, a number of EHS including H. hepaticus and H. bilis have been shown to induce IBD-like disease in animal models utilizing immunodeficient animals. While initial reports found no evidence of EHS in IBD human patients Grehan et al 2004;Huijsdens et al 2004;Zhang et al 2011) in several subsequent studies EHS DNA, detected by PCR, Southern blot and fluorescent in situ hybridization, has been consistently found in a higher proportion of IBD patients compared to control patients (Bohr et al 2004;Oliveira et al 2004Oliveira et al , 2006Laharie et al 2009;Thomson et al 2011). In addition, there have been a number of reports of the findings of Helicobacteraceae DNA in children presenting with IBD (Zhang et al 2006;Man et al 2008;Kaakoush et al 2010).…”

<a name="home"></a>The role of IFN-gamma and IL-4 in gastric mucosa inflammation associated with Helicobacter heilmannii type 1 infection

“…Bacterial viability was assayed by checking motility by phase contrast microscopy. Mucus negative for H. heilmannii had a negative urease test, did not reveal any spiral bacteria in the smears and was PCR negative for the genus Helicobacter (28).…”