I was intrigued by your post as my son was diagnosised with AS last summer. We went to several doctors with conflicting diagnosis. The problem was he wasn't presenting the classic symptoms of the disease, but he does have HLA B27. He took one does of Humara and came down with a sinus infection 12 days later. He has had chronic sinus infections since he was young and was treated with several different antibiotics. I took him to a nutrionist who is also a scientist and was told he probably had the Klebsiella bacteria. I was not aware of the link between the bacteria and AS until I saw this posting. He will be tested later this week for the bacteria. Does anyone know of a treatment for the bacteria?