Spondyloarthropathies
Radiograph	Disease	HLA-B27	Sacroiliitis	Arthritis	Other Tissues
	Ankylosing Spondylitis	++++	++++	++	Uveitis, Aortitis
	Reiter Syndrome	+++	+++	++	Uveitis, Conjunctivitis, Urethritis
	Psoriatic Arthritis	+	++	+++	Psoriasis, Conjunctivitis, Iritis
	Enteropathic Arthritis	+++	+	++	Inflammatory bowel disease

The spondyloarthropathies are a diverse group conditions characterized by an inflammatory arthritis that involves the spine and/or peripheral joints, along with additional organ system involvement. Most of them are marked serologically by the presence of the tissue antigen known as HLA-B27. These conditions can be chronic and progressive (ankylosing spondylitis), relapsing or recurrent (Reiter syndrome), or variable (psoriatic and enteropathic arthritis).

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