title: Association of Streptococcus bovis presence in colonic content with advanced colonic lesion.
abstract: OBJECTIVE
  To prospectively examine the association between presence of Streptococcus bovis (S. bovis) in colonic suction fluid and the endoscopic findings on colonoscopy.
  
  
  METHODS
  From May 2012 to March 2013, 203 consecutive patients who underwent colonoscopy for any reason were enrolled in the study. Exclusion criteria included: antibiotic use in the previous month, age younger than 18 years, and inadequate preparation for colonoscopy. The colonoscopy was performed for the total length of the colon or to the occluding tumor. The endoscopic findings were registered. Samples were obtained proximal to the colonoscopic part of the suction tube from each patient and sent to the clinical microbiology laboratory for isolation and identification of S. bovis. Samples were incubated in enrichment media with addition of antibiotic disks for inhibition of growth of Gram-negative rods. The samples were seeded on differential growth media; suspected positive colonies were isolated and identified with Gram staining, catalase, and pyrrolidonyl arylamidase tests, and further identified using a VITEK2 system. Statistical analyses were performed using the Student's t and χ(2) tests.
  
  
  RESULTS
  Of the 203 patients recruited, 49 (24%) patients were found to be S. bovis carriers; of them, the endoscopic findings included: 17 (34.7%) cases with malignant tumors, 11 (22.4%) with large polyps, 5 (10.2%) with medium-sized polyps, 6 (12.2%) with small polyps, 4 (8.1%) with colitis, and 6 (12.2%) normal colonoscopies. Of 154 patients found negative for S. bovis, the endoscopic findings included: none with malignant tumors, 9 (5.8%) cases with large polyps, 11 (7.1%) with medium-sized polyps, 26 (16.9%) with small polyps, 7 (4.5%) with colitis, and 101 (65.6%) normal colonoscopies. S. bovis (Gram-positive coccus) is considered part of the normal intestinal flora. There is an association between S. bovis bacteremia and colonic neoplasia. It is not well understood whether the bacterium has a pathogenetic role in the development of neoplasia or constitutes an epiphenomenon of colorectal neoplasms. There was a clear relationship between positivity for S. bovis in colonic suction fluid and findings of malignant tumors and large polyps in the colon.
  
  
  CONCLUSIONS
  There is an association between S. bovis bacteremia and malignant colonic lesions; this should prompt for development of a reliable screening method for advanced colonic lesions.
authors.affiliation: Maya Paritsky, Department of Gastroenterology, Baruch Padeh Medical Center, Poria, Lower Galilee 15208, Israel.
authors.forename: Maya
authors.initials: M
authors.lastname: Paritsky
authors.affiliation: Maya Paritsky, Department of Gastroenterology, Baruch Padeh Medical Center, Poria, Lower Galilee 15208, Israel.
authors.forename: Nina
authors.initials: N
authors.lastname: Pastukh
authors.affiliation: Maya Paritsky, Department of Gastroenterology, Baruch Padeh Medical Center, Poria, Lower Galilee 15208, Israel.
authors.forename: Diana
authors.initials: D
authors.lastname: Brodsky
authors.affiliation: Maya Paritsky, Department of Gastroenterology, Baruch Padeh Medical Center, Poria, Lower Galilee 15208, Israel.
authors.forename: Natalya
authors.initials: N
authors.lastname: Isakovich
authors.affiliation: Maya Paritsky, Department of Gastroenterology, Baruch Padeh Medical Center, Poria, Lower Galilee 15208, Israel.
authors.forename: Avi
authors.initials: A
authors.lastname: Peretz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003106:Colon / Q000382:microbiology* / Q000473:pathology; D003110:Colonic Neoplasms / Q000382:microbiology* / Q000473:pathology; D003111:Colonic Polyps / Q000382:microbiology* / Q000473:pathology; D003113:Colonoscopy; D052978:Disk Diffusion Antimicrobial Tests; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013290:Streptococcal Infections / Q000175:diagnosis / Q000382:microbiology*; D016985:Streptococcus bovis / Q000302:isolation & purification*; D047368:Tumor Burden; D055815:Young Adult
keywords: Colon cancer; Colonoscopy; Culture; Screening; Streptococcus bovis