Hi there and welcome. I'm so sorry to hear about your little one, that must be so tough
Ok, we have a few things to cover:
1.
The parents of kids with IBD forum is here. That's the forum Trysha above mentioned. It will be invaluable for you. There are parents with kids there who are on the same treatment as you.
2. You can read more about his current nutrition treatment
here in our enteral nutrition forum.
3. The thing on his legs is called erythema nodosum. It is what is called an "extra intestinal manifestation" of Crohn's Disease. We have a few thread about it in our
skin forum here. In my opinion, it's likely a nutrient deficiency of some sort causing it. It is also a rare side effect of a medication called Pentasa.
4. We have a forum dedicated to
Imuran located here where you can educate yourself about it. Did he have TPMT testing done before he was put on it?
Let's start there. We're here for you. I know this is an overwhelming time but you're not alone. Let us know how we can help. One of my biggest suggestions is to educate the heck out of yourself about this disease so you can advocate for you son.
All my best to you and your family.