My son was diagnosed with Ulcerative Colitis at age 7, 7 years ago. However, a second opinion said it is not UC but it is Crohns. His marker was negative for Crohns but I was told this doesn't matter. His symptoms during a flare up are rectal bleeding and joint pain. His pathology on colonoscopy did not look typical but he was still diagnosed with Crohns. He usually has an elevated eosinophil count, his last result was 0.45 10^3/UL, normal being 0.00-0.27. This has never been addressed and he has begun experiencing irregular heart rhythm and groin pain (comes and goes). Several years ago his pediatrician said he had a sinus arrythmia (no rhythm strip or EKG done) and it was fairly common in kids. I have always worried that he was not diagnosed correctly.

This cannot be diagnosed on line. If you are unhappy with his medical care you need to consult with another Physician - or two or three.

I'm sure you've researched the subject so I am not posting links.