The purpose of this study for children with a new diagnosis of Crohn's disease is to identify biomarkers found in the blood or stool to help predict which children are at risk of developing complications.

It is estimated that between 15-20% of children with Crohn's disease will develop complications that can require surgery within the first three years of diagnosis. The purpose of this study for children with a new diagnosis of Crohn's disease is to identify biomarkers found in the blood or stool to help predict which children are at risk of developing complications.

A total of 2000 children with newly-diagnosed Crohn's disease will be enrolled within 30 days of diagnosis. Up to 28 medical sites in the United States and Canada will participate in the study.

Inclusion Criteria:

• Males and females younger than 17 years of age (before their 17th birthday). An upper limit of 17 years of age was selected as important inclusion criteria to maximize the number of potential subjects that would be diagnosed and followed by a pediatric gastroenterologist for at least 3 years.
• Confirmed or suspected diagnosis of Crohn's disease based on standardized diagnostic criteria. The enrollment should occur within 30 days of diagnosis.
• Able to provide written informed consent or the ability to obtain written informed consent from the parents or patient's legal guardian in conjunction with youth assent.
• Consented to have specimens tested for genetics and immune responses.
• Access to follow-up data for a minimum of 36 months after diagnosis.
• Final eligibility will be determined by the health professionals conducting this clinical trial.

Exclusion Criteria:

• Infectious colitis.
• Final eligibility will be determined by the health professionals conducting this clinical trial.

Study population will consist of children newly diagnosed with Crohn's disease at primary care clinics.