Immunoglobulin A intheskinofpatients with ankylosing spondylitis

studies were carried out in 21 patients with ankylosing spondylitis (AS)andtheresults comparedwiththosefor18healthy subjects. The mostprominent finding was thepresence ofIgAindermalvessels ofpatients withAS (71% compared with17%ofthecontrol group). IgGandIgMcutaneousdeposits were alsoobserved in patients withAS,butthese results didnotdiffer fromthoseofthecontrol group. A renalbiopsy wasperformed inthree ofthepatients presenting withunexplained microscopic haematuria. One ofthemhadanIgAnephropathy, butno correlation was foundbetweenkidneyandskindeposits ofIgA.Thesefindings suggestthatIgAcutaneousdeposits inAS are not a markerofIgA nephropathy butstress therole ofimmunoglobulin A inthepathogenesis ofthisdisease.