title: Reduced free protein S levels in patients with inflammatory bowel disease: prevalence, clinical relevance, and role of anti-protein S antibodies.
abstract: We evaluated free plasma levels of protein S, a natural anticoagulant factor, the prevalence of anti-protein S antibodies, a possible cause of protein S deficiency, and their correlation with anti-phospholipid antibodies in 53 patients with inflammatory bowel disease (IBD) and 53 age- and sex-matched controls. Mean free plasma protein S levels (+/- SD) were significantly lower in IBD patients (0.98+/-0.32 IU/ml) than in controls (1.06+/-0.28 IU/ml) (P < 0.05); only one patient showed protein S deficiency. Specific antibodies to protein S were found in four IBD patients (7.5%) and in one control (1.9%) (P = NS). Five IBD patients (9.4%) and none of the controls showed anti-phospholipid antibodies (P < 0.06). No correlation was found between free protein S levels and anti-protein S antibodies or between anti-protein S and anti-phospholipid antibodies. In conclusion, free plasma protein S levels are slightly but significantly decreased in IBD patients. The prevalence of anti-protein S and antiphospholipid antibodies is increased in IBD patients. Anti-protein S antibodies do not appear to determine low protein S levels or to overlap with or belong to anti-phospholipid antibodies.
authors.affiliation: Angelo Bianchi Bonomi Haemophilia and Thrombosis Center, IRCCS Ospedale Maggiore, Department of Internal Medicine, University of Milan, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Saibeni
authors.forename: M
authors.initials: M
authors.lastname: Vecchi
authors.forename: C
authors.initials: C
authors.lastname: Valsecchi
authors.forename: E M
authors.initials: EM
authors.lastname: Faioni
authors.forename: C
authors.initials: C
authors.lastname: Razzari
authors.forename: R
authors.initials: R
authors.lastname: de Franchis
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D005260:Female; D006801:Humans; D015151:Immunoblotting; D015212:Inflammatory Bowel Diseases / Q000097:blood* / Q000276:immunology*; D008297:Male; D010743:Phospholipids / Q000276:immunology; D017293:Protein S / Q000032:analysis* / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D010743:Phospholipids; D017293:Protein S