This is a retrospective, case control study of inflammatory bowel disease. This study will analyze the phenotypic characteristics of inflammatory bowel disease in the Southeast Asian population and will help describe clinical characteristics and serologic profiles in Southeast Asians with inflammatory bowel disease, comparing the phenotype differences to historical Caucasian controls. The data from this study will help identify the phenotype characteristics of different ethnic groups and study the epidemiological patterns of the disease.

This study is a retrospective, case control study of inflammatory bowel disease characteristics in patients with origins from the Indian sub-continent. Patients will be selected from the IBD registry maintained at respective institutions. Subjects from the Indian sub-continent will be identified using their country of birth, parents' ethnicity, number of years since leaving the country of birth, and number of years residing in the United States.

Using both electronic and paper databases, demographic information regarding age, gender, body mass index, smoking history, dietary habits; medical history such as type of IBD, IBD symptoms, location and behavior, medication use (past and current), history of other autoimmune disorders; surgical history (IBD and non-IBD related); laboratory indices such as IBD serology, Thiopurinemethyltransferase (TPMT), and infliximab levels will be collected.

Demographics will be compared between groups using descriptive statistics. Using univariate analysis, variables that are significantly different will be identified. Conditional logistic regression will then be performed to identify those clinical variables that are statistically significant.

The study duration will be one year from IRB approval.

Inclusion Criteria:

• Patients with origins from the Indian sub-continent
• Patients will be selected from the IBD registry maintained at respective institutions.

Patients will be selected from the IBD registry maintained at respective institutions. Subjects from the Indian sub-continent will be identified using their country of birth, parents' ethnicity, number of years since leaving the country of birth, and number of years residing in the United States.