Ankylosing Spondylitis: Could my starch intolerance be linked to AS?

"I recently discovered the existence of ankylosing spondylitis (AS) while doing a web search on starch intolerance. Every time I eat starchy food the pain in my lower back, which I have had for more than 20 years, flares up. At the same time I suffer chronic cramping in my intestines. The more I read about AS, the more I am convinced it is the cause of my problems. I've been told the next stage is to see my GP to have a blood test for HLA-B27. Over the years I have often gone to my GP for bowel and back problems and I have been made to feel like a hypochondriac. Twenty years ago I was diagnosed with inflammation of the sacroiliac joint. I don't know what my GP will say if I ask for a blood test, but I imagine it will be dismissive. I've looked into a private test, but it will cost £200 and I can't afford it. What should I do?"

Dr Fred Kavalier answers your health question:

Ankylosing spondylitis is an unusual form of arthritis that affects men more commonly than women. The first symptoms are usually pain and stiffness in the lower spine. The pain of AS is worse after rest and inactivity. As the condition progresses, the spine gets stiffer, and eventually is fused in a stooped position. I do not think your intolerance of starchy food is likely to be linked to AS. The HLA-B27 blood test will not diagnose AS. Most people who carry HLA-B27 in their blood do not have AS. If your back pain is being caused by AS, it should be easy for a diagnosis to be made on the basis of history, a physical examination, and an X-ray of your sacroiliac joints. Check out the website of the National Ankylosing Spondylitis Society – www.nass.co.uk.

Please send your questions and suggestions to A Question of Health, 'The Independent', Independent House, 191 Marsh Wall, London E14 9RS; fax 020-7005 2182 or e-mail to health@independent.co.uk. Dr Kavalier regrets he is unable to respond personally to questions.