Hello, I Am A 34 Years Old Female. I Have

Hello, I am a 34 years old female. I have back pain for year and a half and looks like noone knows what is causing it. I just had a second MRI done because my rheumathologist thinks I may have ankylosing spondylitis. I just got a copy of the MRI and I am really confused what I have. I will appreciate if a doctor explain it in simple English and tell me if there is a cure and what could be the best treatment in my case.
Below are my MRI findings

Thank you in advance for your time.

Moderate disc space narrowing is seen at the l4-l5 and l5-s1 levels.Mild endplate edema and fatty marrow changes are noted on these levels, favored to represent Modic type 1 and 2 endplate changes.
A small focal area of edema is noted on the iliac side of the left sacroiliac joint posterosuperiorly