Immune Regulation in Ulcerative Colitis or Crohn s Disease

* INCLUSION CRITERIA: 1. Patients with a verifiable diagnosis of Crohn s disease, ulcerative colitis, or IBD known to be associated with a co-existing condition and which is supported by characteristic clinical features, radiographic or endoscopic findings, or consistent histopathologic mucosal changes OR 2. Patients with clinical features consistent with an unclassified inflammatory bowel disease and histologic evidence of inflammation of the intestine OR 3. Patients with any clinical features consistent with inflammatory bowel disease (intestinal inflammation), including but not limited to abdominal pain, fistulae, weight loss, diarrhea, hematochezia or melena or suggestive extra-intestinal symptoms (pyoderma, erythema nodosum, axial and articular arthralgias, uveitis, fatigue, fever), in which a diagnosis has not been verified. OR 4. Patients who have a defined genetic syndrome linked to inflammatory bowel disease risk with or without symptoms or findings consistent with IBD 5. All subjects to be enrolled will be between ages 0-75 (Participants coming to the NIH Clinical Center must meet age and weight requirements of the clinical center, but \> 18 must years old for patients without IBD and may be as young as 0-2 years old for mail-in samples). 6. To participate in the research biopsies during endoscopy, subjects must have the following lab values within two weeks of the procedure: * Hematocrit \> 30% * Platelet count \> 100,000 * PT INR \< 1.3 or PTT prolonged by \< 3 seconds 7. Ability to consent to the protocol on their own. INCLUSION CRITERIA FOR HEALTHY VOLUNTEERS: 1. Must be willing to undergo blood draw and/or upper endoscopy and colonoscopy with biopsy to obtain material for research purposes. 2. Must be \>=18 years old. 3. Must be willing to submit samples for storage. INCLUSION OF EMPLOYEES IN THE NIH INTRAMURAL STUDIES: NIH employees and members of their immediate families may participate in this protocol. We will follow the Guidelines for the Inclusion of Employees in NIH Research Studies and will give each employee a copy of the NIH information sheet on Employee Research Participation. For NIH employees: 1. Neither participation nor refusal to participate will have an effect, either beneficial or adverse, on the participant s employment or work situation. 2. The NIH information sheet regarding NIH employee research participation will be distributed to all potential subjects who are NIH employees. 3. The employee subject s privacy and confidentiality will be preserved in accordance with NIH Clinical Center and NIAID policies, which define the scope and limitations of the protections. 4. For NIH employee subjects, consent will be obtained by an individual independent of the employee s team. Those in a supervisory position to any employee and co-workers of the employee will not obtain consent. The protocol study staff will be trained annually on obtaining potentially sensitive and private information from co-workers or subordinates. This training will be reinforced as needed, at weekly team meetings. EXCLUSION CRITERIA: 1. Failure to meet the inclusion criteria. 2. Any medical, psychiatric, or social conditions which, in the opinion of the investigators, would make participation in this protocol not in the best interest of the subject. EXCLUSION CRITERIA FOR HEALTHY VOLUNTEERS: 1. History of inflammatory bowel disease. 2. Acute systemic or intestinal infection requiring antibiotics 3. Any condition that, in the investigator s opinion, places the patient at undue risk by participating in the study.