A 12 year old female, with a history of a rectal abscess, pr…

A 12 year old female, with a history of a rectal abscess, presents to her primary care physician with a complaint of colicky, right lower quadrant pain and diarrhea for several months.  She admits to a 10 pound weight loss during that time period.  A CT abdomen and pelvis demonstrates a severely inflamed ileum.  She undergoes a colonoscopy several weeks later that demonstrates skip lesions and deep linear ulcers throughout the ascending colon.  What is the most likely diagnosis?