<prompt> Which of the following is NOT associated with ankylosing spondylitis:SLEReiters syndromePsoriatic ahropathyCrohns disease  <response>: Ankylosing spondylitis is an inflammatory disorder of unknown cause Primarily affects the axial skeleton; peripheral joints and extraaicular structuresOlder names: Marie-Strumpell disease or Bechterews diseaseTypically associated with HLA-B27ref:Harrisons 18e p2774, 2775 