Colonoscopy after Streptococcus bovis Bacteremia: Do We Need More Data?

Abstract

Purpose:Streptococcus bovis (SB) is a group D non- enterococcal Streptococcus; an association between SB bacteremia (SBB) and colorectal cancer (CC)/adenomatous polyps(AP) has been established and colonoscopy is considered mandatory after the diagnosis. The knowledge however about the true pathophysiologic mechanism is lacking and adenomatous polyps are frequent in general population over 50. The aim of the study was to investigate the prevalence of CC/AP in SBB patients. Methods: The study was made on 26 consecutive patients (8 women, 18 men, medium age at diagnosis 63.3 yrs, range 49-78 yrs) who had positive hemocolture for SB (Group A). Complete colonoscopy and biopsies or polypectomy were performed in all patients. In the same way colonoscopy was made on 26 consecutive asymptomatic patients(6 women, 20 men, medium age 58.1 yrs range 49-69) as a control group (Group B). Data were analysed by Fisher's exact test. Results: In Group A, 14 patients (53.8%) had neoplastic lesions (12 AP = 46.1% and 2, CC = 7.7%); in Group B 8 patients had AP (30.7%). No patient had CC. No statistical significance was found between the two groups. (p= 0.16) Conclusion: The study was made on small groups of patients and the medium age of Control Group was 5 years lower than Group A. The detection rate of CC or AP in SBB patients is higher than expected but the differences between the two groups are not statistically significant. The reasons of the association between SB infection and colon neoplasia (in particular with non ulcerated lesions) are still not clear. At the moment colonoscopy should be recommended after the diagnosis of SBB but more data might be needed.