ANKYLOSING-SPONDYLITIS AND SECRETOR STATUS - A REEVALUATION

Non-secretion of ABO blood group substances in body fluids is associat ed with susceptibility to some bacterial infections. Non-secretors wer e previously found to be over-represented in patients with ankylosing spondylitis (AS) (49%) compared to controls (27%). Re-evaluation of se cretor status in a population of 92 AS patients and 103 controls revea led identical proportions of non-secretors (28%). Of 43 patients studi ed in both surveys, 6/22 typed initially as non-secretors proved to be secretors using both haemagglutination inhibition assay (HAI) and enz yme-linked immunosorbent assay (ELISA) techniques. Loss of secreted bl ood group antigens in the saliva is the cause of this mis-typing. Care ful attention to the method of collection, handling and preservation o f saliva specimens is essential for accurate assessment of secretor st atus. Therefore, there is no link between secretor status and AS.