Diverticular disease is one of the most prevalent disorders in western societies, and complications of diverticulosis are frequent, costly and often recurrent. Identification of individuals at high risk for these complications is of great clinical importance. However, few risk factors have been identified, and no preventative strategies exist short of segmental colectomy. The role of human intestinal microbiota in disease is increasingly being recognized. Recent advances in DNA sequencing technology now enable cost-effective, large-scale profiling of the intestinal microbiota, and provide a new quantitative tool for the study of gastrointestinal disorders. The intestinal microbiota represent an attractive target for study in diverticular disease since they can be sampled, providing the basis for a potential biomarkers and preventative interventions. The overall goal of this proposal is to profile the intestinal microbiota in both patients with asymptomatic diverticulosis and those with diverticulosis complicated by acute diverticulitis. We plan to use a combination of state-of-the-art molecular and novel metagenomic approaches, and to determine whether quantitative analysis of the intestinal microbiome can be used to differentiate diverticular disease phenotypes. Uncovering such differences would be of great potential clinical significance, since they could be modeled to (i) enable outcome prediction and risk stratification;(ii) provide avenues for treatment and prevention, and (iii) reveal insight into pathogenesis. In pursuit of this goal, we plan to profile the intestinal microbiome in diverticular disease using two parallel study cohorts: (i) 100 patients with asymptomatic diverticulosis recruited prospectively from the outpatient endoscopy units of two large teaching hospitals;and (ii) 100 prospectively identified patients with diverticulosis complicated by acute diverticulitis. Replicate fecal DNA samples will be collected longitudinally from each study individual using well-tested methods. We will then perform intestinal microbiome profiling using a combination of metagenomic Terminal Restriction Fragment Polymorphism (tRFLP) analysis and a novel digital 16S fingerprinting approach utilizing next-generation sequencing. These data will yield deep, high-resolution fingerprints of the intestinal microbial metagenome in each disease population, which can then be compared to identify composite biomarkers that predict disease complications.

Public Health Relevance

This study will use innovative molecular techniques to profile the intestinal microbiota in both patients with asymptomatic diverticulosis and those with diverticulosis complicated by diverticulitis. The identification of a unique microbial metagenomic fingerprint in patients with diverticulosis complicated by diverticulitis could provide the basis for a non-invasive screening tool for at-risk individuals, and/or for directed preventative interventions. This study has important public health implications since diverticulosis is extremely common and there is currently no way to identify patients at risk for complications and preventative strategies are limited.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK084157-03
Application #
8294925
Study Section
Gastrointestinal Mucosal Pathobiology Study Section (GMPB)
Program Officer
Karp, Robert W
Project Start
2010-07-26
Project End
2015-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
3
Fiscal Year
2012
Total Cost
$323,886
Indirect Cost
$62,214
Name
University of Washington
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
Cao, Yin; Strate, Lisa L; Keeley, Brieze R et al. (2018) Meat intake and risk of diverticulitis among men. Gut 67:466-472
Liu, Po-Hong; Cao, Yin; Keeley, Brieze R et al. (2017) Adherence to a Healthy Lifestyle is Associated With a Lower Risk of Diverticulitis among Men. Am J Gastroenterol 112:1868-1876
Strate, Lisa L; Keeley, Brieze R; Cao, Yin et al. (2017) Western Dietary Pattern Increases, and Prudent Dietary Pattern Decreases, Risk of Incident Diverticulitis in a Prospective Cohort Study. Gastroenterology 152:1023-1030.e2
Strate, Lisa L; Gralnek, Ian M (2016) ACG Clinical Guideline: Management of Patients With Acute Lower Gastrointestinal Bleeding. Am J Gastroenterol 111:459-74
Wheat, Chelle L; Strate, Lisa L (2016) Trends in Hospitalization for Diverticulitis and Diverticular Bleeding in the United States From 2000 to 2010. Clin Gastroenterol Hepatol 14:96-103.e1
Hullar, Meredith A J; Burnett-Hartman, Andrea N; Lampe, Johanna W (2014) Gut microbes, diet, and cancer. Cancer Treat Res 159:377-99
Tseng, Huei-Hun Elizabeth; Hullar, Meredith A J; Li, Fei et al. (2013) A microbial profiling method for the human microbiota using high-throughput sequencing. Metagenomics (Cairo) 2:235646
Templeton, Adam W; Strate, Lisa L (2013) Updates in diverticular disease. Curr Gastroenterol Rep 15:339
Hullar, Meredith A J; Lampe, Johanna W (2012) The gut microbiome and obesity. Nestle Nutr Inst Workshop Ser 73:67-79