Sharon, it's entirely possible that your mother has had undiagnosed AS for many years. Women are often misdiagnosed because the disease presents so differently in us than it does in men, and men have been the foundation of almost all the research done on AS. Someday, the medical community is going to figure out that men and women are not the same physiologically. Until that day, women like your mother will continue to be un or mis diagnosed for many diseases.
Which blood test did they do on her, by the way? HLA-B27 is the only one that I know of when it comes to AS. Is it possible they checked her for the rheumatoid factor? If so, then she may have Rheumatoid Arthritis not AS (or both, which is possible).
Many hugs,
