Hi Alfred and Welcome to HealingWell!! :)
You asked if PPI's caused IBS? I just posted a thread on the Allergy Forum today re "Asthma Risk Higher for People with Bowel Disease" http://www.nlm.nih.gov/medlineplus/news/fullstory_26820.html
I don't think the PPI's cause IBS (my opinion only), however, allergies, along with the inflammation that is brought on by them, may play a bigger part in a lot of ailments not yet identified.
Thanks for sharing.
"Because he is he and I am I."......E. V. Lucas