<unk>  (SpA) are a group of chronic inflammatory arththropathies which are inter-related to each other.<unk> " refers to the fact that autoimmune antibodies are not found in these diseases. SpA primarily affects axial skeleton but may also have peripheral as well as extra-articular involvement. Individuals affected with<unk>  SpA are generally genetically predisposed to have positive major histocompatibility complex (MHC) class I molecule HLA-B27. As the diseases feature overlap, it is difficult to make a precise diagnosis; hence, the diseases are monitored and treated on the basis of clinical presentation. Common clinical manifestations includes sacroiliitis, peripheral arthritis, and enthesitis. Extra-articular involvement depends on the disease such as skin manifestations for psoriatic arthritis, gastrointestinal tract manifestations for enteropathy associated arthritis, and ocular and genitourinary manifestations for reactive arthritis.
Seronegative spondyloarthritis
Enteropathic arthropathy
Psoriatic arthritis pathophysiology
Polymyalgia rheumatica
Systemic lupus erythematosus
Reactive arthritis
Psoriatic arthritis
Spondyloarthropathy