Baseline available SIJ MRI 11 years ago at age 28

SIJ MRI 2014, only T1w and T2FSE non fat sat images done

1 year ago I reported chronic bilateral sacroilitis with questionable minimal synovial edema

Now, detailed hx reveals 15 yrs LBP in a 39F.  Carries a dx of RA and has tolerated multiple DMARDs poorly, currently not on therapy.  Referred by orthopedist who tells me she was diagnosed with "spondyloarthropathy in 2015, found to be HLA-B27 positive. All prior Lumbar MRI is essential normal; 2018 exam included Sag STIR images. 

I don't see any real interval change since Nov 2018.  I am told that she has never had other peripheral joint symptoms. Is this actually RA?  Can this be AS (the patient self reports history of AS now) without ankylosis over a course of 5 years?  How would you report this?