Hi Gi-jo-mom,
I'm sorry that your son is going through this. It's hard enough for me to deal with as an adult, so I can imagine how hard it must be as a teenager.
I have had a fistula with seton in place since Feb 2015. My gastro says he would want to see signs of it healing on MRI scans before taking the seton out, so there is no specific length of time. The last MRI showed the tract was still quite large with lots of granulation tissue so I just had an op to scrape some of that out with the aim to promote healing. Sounds like what Sascot's son had.
I am on Humira. I was given the option of Remicade or Humira and told they both work the same way so the choice for Humira was just one of convenience of injections over infusions. I'd be really interested if anyone could point me towards the trials showing that Remicade is more effective? My gastro has specifically said there'd be no point trying Remicade if Humira doesn't work, though he would try Vedolizumab (which as yet has no evidence for fistula healing).
I'm also on Azathioprine (Imuran?) and starting exclusive enteral nutrition (Elemental 028) his weekend. There's not much evidence for the EEN but I figure there's not that much risk either. Gastro thinks it *could* help.
I'm on metronidozole just a short course of 10 days at the moment which is definitely helping it to dry up and feel less sore since my recent surgery, and pentasa long-term. I'm starting to think I should get one of those signatures with my Dx and medications!
Hope your son starts feeling better soon