My mom is in her mid 80's. She has not been diagnosed with AS, and, as far as I know, she has not even asked a DR. if she could have it. However, I suspect from what I'm now seeing (her neck is frozen, so she can't turn her head, her hips hurt her etc.)that she, too might have it. I don't know how long she has had any symptoms. She has dementia, and would not be able to answer that question.
I was diagnosed when I was in my 40's, but I first started having symptoms when I was in my mid 20's.
I'm sure you know that the results from the HLA-B27 test really doesn't mean much. If it comes back negative, it doesn't mean that she doesn't have AS. That's just one diagnostic tool, and in my opinion, not a very good one.
I'm not a doctor, but I don't know why she would be too old.
