The Inflammatory Bowel Disease (IBD) Genetics Consortium is currently recruiting patients with IBD to participate in research studies. We are especially interested in individuals who are members of racial or ethnic minorities or who are undergoing an ileal resection for Crohn’s disease. If you are in one of these groups and would like more information about participating in a Consortium study, please contact us at

FAQ For Patients Undergoing Ileocolic Resection

What is a Research Study?

A research study is when scientists try to answer a question about something that we don’t know enough about. You can also agree to take part now and later change your mind.

What is the purpose of this Research Study?

You may qualify to take part in this research study because you have been diagnosed with Crohn’s disease, and will undergo or very recently underwent ileal resection surgery.

The purpose of this study is gain further understanding of the mechanisms involved in the recurrence of inflammation following ileal resection surgery for Crohn’s disease (CD). One of the most common locations of CD involvement is the end of the small intestine (ileum)1. Reasons for this recurrence remain unclear, however several studies have concluded that smoking increases the risk of postoperative recurrence2,3,4,5,6,7. Postoperative recurrence is also believed to be caused by an interaction of genetic8, immune and microbial features. There are also many unanswered questions regarding the optimal management of patients during the post-operative period with regards to medication, diet and frequency of postoperative monitoring. This study aims to better understand the role of genetics, immune system, environment, medication, smoking and diet in the recurrence of Crohn’s disease after your surgery. We hope that our findings will help your physician better optimize your medication and care. This study is ongoing in several sites across the United States and Canada. We have recruited about 500 participants.

What is classified as recurrence and remission?

Recurrence can either be histological (inflammation is only visible through a microscope), endoscopic (inflammation is visible to your doctor during endoscopy), clinical (you will have increased Crohn’s disease symptoms) or Surgical (your symptoms are severe enough for surgery). Remission is defined as the temporary absence of active disease. Remission can either be endoscopic (no evidence of inflammation during your endoscopy) or clinical (you may have reduced or no symptoms).

What is involved in participation?

If you agree to participate in this study, you will be asked to provide a few extra biopsies during your colonoscopy, we would draw some blood and ask you some questions about your Crohn’s Disease medical history. You may also be asked to provide stool samples. You may also be contacted by our partners at Penn State if you express interest in the diet component of the study.

What do we do with your samples?

Some of the blood we collect will be used for protein expression analysis, some will be used for Whole Exome Sequencing in collaboration with the Broad Institute. The biopsies we collect will be used to measure gene expression analysis.

Will I receive results back?

We will deidentify your data, so any information we collect from you cannot be linked back to you and because of this, we will not be able to give you any results. When the study is over and our results are published, you will be able to read about our findings.

Where can I get more information?

You can find additional resources at the Crohn’s and Colitis Foundation.

  1. Rutgeerts P. and others, “Predictability of the Postoperative Course of Crohn’s Disease”, Gastroenterology, 99.4 (1990), 956–63 ↩︎

  2. William R Ryan and others, “Crohn’s Disease Patients Who Quit Smoking Have a Reduced Risk of Reoperation for Recurrence”", The American Journal of Surgery, 187.2 (2004), 219–25↩︎

  3. Takayuki Yamamoto, “Factors Affecting Recurrence after Surgery for Crohn’s Disease”", World Journal of Gastroenterology, 11.26 (2005), 3971–79↩︎

  4. Mario Cottone, Ambrogio Orlando, and Irene Modesto, “Postoperative Maintenance Therapy for Inflammatory Bowel Disease”", Current Opinion in Gastroenterology, 22.4 (2006), 377–81↩︎

  5. Kwan Mo Yang and others, “Risk Factors for Postoperative Recurrence after Primary Bowel Resection in Patients with Crohn’s Disease”, World Journal of Gastroenterology, 23.38 (2017), 7016–24↩︎

  6. George E. Reese and others, “The Effect of Smoking after Surgery for Crohn’s Disease: A Meta-Analysis of Observational Studies”, International Journal of Colorectal Disease, 23.12 (2008), 1213–21↩︎

  7. Roel Bolckmans and others, “Does Smoking Cessation Reduce Surgical Recurrence After Primary Ileocolic Resection for Crohn’s Disease?”, Diseases of the Colon & Rectum, 63.2 (2020), 200–206↩︎

  8. Manuel Alvarez-Lobos and others, “Crohn’s Disease Patients Carrying Nod2/CARD15 Gene Variants Have an Increased and Early Need for First Surgery Due to Stricturing Disease and Higher Rate of Surgical Recurrence”, Annals of Surgery, 242.5 (2005), 693–700↩︎