There are six types of spondyloarthropathy [SpA]. SpA is also called spondylitis. Ankylosing Spondylitis is one of the SpA diseases. Enteropathic Arthritis is a form of chronic, inflammatory arthritis associated with the occurrence of an inflammatory bowel disease like CD or UC. It is one of the SpA diseases too. Each of the spondylitis diseases has similar symptoms but with some different manifestations. You might want to read about both Enteropathic Arthritis and Ankylosing Spondylitis at the Spondylitis Association of America's web site. They have really good information. Look under about Spondylitis.