Yes, it’s definitely possible and very likely. You might light up on a bone scan though like I did at first. I was diagnosed with AS almost right away. I had sacroilitis show up for years, but after being on biologics for so long then my xrays showed evidence of prior sacroilitis, and now they don’t say anything. It’s very strange. My SI joints still hurt, but not as bad as they did in the beginning years, but I attribute that to continuous biologics since 2005.
My spine has gotten progressively worse. But now I might be more considered as non radiographic axial Spondylitis. I’m HLA negative, but am textbook AS (besides SI fusion lessening). I read Kahn’s book and it describes me exactly, even the same order of symptom appearance. And I’m a woman!