Good question. I had interest in it but never did it.
I hope you find some way and share with us. I tried looking into it a couple of years ago but didn't have the time and energy while I was in Canada. I've been struggling to get my gut to function correctly for a few years now.
HLA-B27 neg; Mis-diagnosed with fibromyalgia in mid-20s.
Vague AS symptoms in 20s and early 30s (no diagnosis).
During age 47 (2015) developed complete axial inflammation (started from from skull and progressed down to sacrum). Included psoriasis. Trigger in scull was reverse blockage in a SCUBA mishap. Straw that broke the camels back was over use of NSAIDs. NSD works well but not perfect. Strong involvement between symptoms and gut integrity.