Thank you for posting your query on XXXXXXX
Well looking into your problem it is possible that you are suffering from the condition known as seronegative spondyloarthropathy
( ankylosing spondylitis
) since you are HLA B 27 positive also . It seems that you have both axial as well as peripheral manifestation as you have pain in back along with swelling in joints .
I will advise you to see a rheumatologist
and get your disease activity assessed . You need to get a CBC , ESR
, CRP , X Ray
pelvis and possible MRI pelvis to look for sacroillitis .
Only after assessment of your disease activity proper treatment will be initiated . Please do not ignore the problem . Physical examination is very important in this disease as various tests like schobers test , figure of 4 test is needed for disease assessment .
So , seek medical advise as soon as possible .