<prompt> HLA B 27 is not seen in which of the followingAnkylosing spondylitisReiters syndromeRheumatoid ahritisPsoriatic ahritis  <response>: Ref Robbins 9e p215 HLA and diseases, the association of B27 with ankylosing spondylitis AS is the strongest. The B27 antigen is present in over 90 of patients with AS as com- pared with the B27 prevalence of 8 in Caucasians in general. A strong but slightly minor association has also been found between B27 and Reiters syndrome RS, reactive ahritis ReA, and acute anterior uveitis AAU. It is negative in rheumatoid ahritis 