Firstly, I'm sorry about
your son's diagnosis. It's sh!t when a child gets this crappy disease. But also, I just wanted to second Charlie's suggestion of enteral nutrition. With a child, I would try that before I would try steroids. He doesn't need to be on said diet permanently because, let's face it, it's not a whole lot of fun for a child. But it's worth trying for a few weeks/months just to (hopefully) get the immediate flare-up under control.
Again, I understand your doubts about
the Humira but it sounds like your boy has severe disease to be honest :-/ For whatever it's worth, Humira is safer than long-term prednisone: a lot, lot safer.
Meanwhile, if you need to convince your GI that enteral nutrition is the way to go, here is an article you can print off to show him. /www.ncbi.nlm.nih.gov/pmc/articles/PMC4462720/
Dx Crohn's in June 2000. (Yay )
Tried: 5-ASAs, azathioprine, 6MP, Remicade, methotrexate, Humira, diets.
1st surgery 20/2/13 - subtotal colectomy with end ileostomy.
2nd surgery 10/7/15 - ileorectal anastomosis. Stoma reversed and ileum connected to the rectum.
Current status: Chronic flare. Do I have any other kind?
Current meds: 50mg 6MP; Entyvio (started 3/11/16)