title: C1-inhibitor autoantibodies in SLE.
abstract: The presence of anti-C1-inhibitor (anti-C1-INH) autoantibodies is a hallmark of acquired C1-inhibitor deficiency. However, only scarce data are available on their prevalence, diagnostic value, and/or significance in systemic lupus erythematosus (SLE). In a multicentre study, we determined the levels of autoantibodies to C1-inhibitor in sera from 202 patients with SLE and 134 healthy controls. Additional clinical and laboratory parameters, such as organ involvement, as well as anti-C1q, anti-double-stranded DNA antibody, erythrocyte sedimentation rate, C-reactive protein, C3 and C4 serum complement levels have been studied in patients. The level of anti-C1-INH IgG was significantly higher (p = 0.034) in SLE patients, than in the controls. A high anti-C1-INH level of > or =0.4 U/ml (mean of controls + 2 SD) was found in 17% of the patients, but in only 4% of the controls (p = 0.0003). The SLEDAI score was significantly higher (p = 0.048) and the duration of SLE was significantly longer (p = 0.0004) among patients with elevated anti-C1-INH levels compared with patients without this autoantibody (median disease duration 8 vs. 17 years, respectively). Anti-C1-INH level was not correlated with any other laboratory parameter or organ manifestation of the disease. These findings indicate that the anti-C1-INH level is higher in SLE patients than in healthy controls and furthermore, the anti-C1-INH level correlates with the duration and activity of the disease.
authors.affiliation: 3rd Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: T
authors.initials: T
authors.lastname: Mészáros
authors.forename: G
authors.initials: G
authors.lastname: Füst
authors.forename: H
authors.initials: H
authors.lastname: Farkas
authors.forename: L
authors.initials: L
authors.lastname: Jakab
authors.forename: G
authors.initials: G
authors.lastname: Temesszentandrási
authors.forename: G
authors.initials: G
authors.lastname: Nagy
authors.forename: E
authors.initials: E
authors.lastname: Kiss
authors.forename: P
authors.initials: P
authors.lastname: Gergely
authors.forename: M
authors.initials: M
authors.lastname: Zeher
authors.forename: Z
authors.initials: Z
authors.lastname: Griger
authors.forename: L
authors.initials: L
authors.lastname: Czirják
authors.forename: R
authors.initials: R
authors.lastname: Hóbor
authors.forename: A
authors.initials: A
authors.lastname: Haris
authors.forename: K
authors.initials: K
authors.lastname: Polner
authors.forename: L
authors.initials: L
authors.lastname: Varga
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D050718:Complement C1 Inhibitor Protein / Q000276:immunology*; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood*; D008297:Male; D008875:Middle Aged
chemical_list: D001323:Autoantibodies; D050718:Complement C1 Inhibitor Protein