Low Prevalence of Helicobacter pylori Infection in IBD Patients from a Predominantly African/Caribbean Urban Center

Abstract

Purpose:Helicobacter pylori (HP) is a gram negative bacterium which can survive the harsh acidic environment of the human stomach, infecting 50% of people. In developing countries, this value can be up to 90%. HP infection is associated with the development of peptic ulcer disease, gastric cancer, and MALT lymphoma. Risk factors include lower socioeconomic status, overcrowding, poor hygiene, and living in a developing country. Published rates of HP infection in the Caribbean ranges from 55%-70%. HP detection can include histologic testing of the endoscopic biopsy specimens or fecal antigen. The latter is often also used to document HP eradication after therapy or to monitor progression in the presence of continued symptoms. Patients with inflammatory bowel disease (IBD) have lower HP infection rates than the rest of the population. In fact, some studies believe HP infection may be protective in the yet to be determined factors that are causative of IBD. A recent study demonstrated that the presence of HP was inversely associated with IBD, ulcerative colitis (UC), Crohn's disease (CD), and indeterminate colitis. A recent meta-analysis reported IBD populations having a HP prevalence of 27.1% and control populations with 40.9%. However, this impact in underserved urban areas, is not well-described. The aim of our study was to determine the prevalence of HP in an urban population of Afro-Caribbean patients with IBD. Methods: IBD patients (N=347) were identified by ICD-9 coding and were retrospectively evaluated for the presence of HP by positive histology. A control group was determined by a database of patients with abdominal symptoms (N=321). Both groups were compared for HP status and demographic data. The IBD group was evaluated on the basis of UC and CD. Results: The IBD cohort comprised a group with an average age 45 years, 86% black, 62% UC, 31% CD, and 7% indeterminate colitis. The control group was an older cohort at 59 years, and 67% black. The IBD group was found to have an HP prevalence of 3.4%, as compared to 10.3% in our control group. Both these values are significantly lower than those reported in the literature, but consistent with the finding of lower HP rates in IBD patients. The control group was evaluated from a database of N=321 patients seen from 2009-2012. The average age was 59 years. 67% were black, 24% Afro-Caribbean. HP status was determined using biopsy or by HP stool antigen as a surrogate. Conclusion: These findings report a lower HP prevalence in both groups in this urban Afro-Caribbean population, as compared to those expected to be found in a U.S. cohort or either IBD (3.4%) or non-IBD (10.3%) populations. However, the lower HP prevalence, as compared to the control group, is consistent with recent literature.