Association of inflammation with raised serum IgA in ankylosing spondylitis
Annals of the Rheumatic Diseases, 1980, 39, 545-549
P. COWLING,1 R. EBRINGER,2 AND A. EBRINGER1
From the * Immunology Unit, Department of Biochemistry, Queen Elizabeth College, London W8, and the 2Department of Rheumatology, Middlesex Hospital, Arthur Stanley House, Tottenham Street, London W1P 9PG
There is evidence that gastrointestinal infection may be an important aetiological factor in ankylosing spondylitis (AS). Sacroiliitis and AS are common sequelae in persons who develop arthritis or Reiter's disease after dysenteric infection with salmonella, shigella, or Yersinia enterocolitica.1 We have reported an increased isolation of Klebsiella pneumoniae from the faeces of AS patients before and during active phases of the disease2 or during episodes of acute anterior uveitis.3 Investigation by lymphangio-graphy has shown that pelvic and paraspinal lymphadenopathy precedes the radiological changes in AS4. Raised levels of serum IgA in patients with AS have been reported5"8. Plasma cells in the gut associated lymphoid tissue are the major source of serum IgA,9 and investigations in animals raised in germ-free conditions have shown that after oral immunisation the main specific plasma cell response is IgA in character and nearly all the circulating specific antibody is IgA.10
We report here our studies on serum immuno-globulin levels in AS.
Accepted for publication 4 December 1979 Correspondence to Dr R. Ebringer.