title: Cardiolipin antibodies and null alleles of C4 in black Americans with systemic lupus erythematosus.
abstract: Twelve of 44 black American patients with systemic lupus erythematosus (SLE) (27%) studied during periods of disease activity had increased levels of IgG antibodies against cardiolipin (IgG aCL). IgG aCL occurred almost exclusively in patients who had a partial genetic deficiency of C4A or C4B. Eleven of 29 patients (38%) with a C4A or C4B deficiency allele had IgG aCL, compared with 1/15 patients (7%) who did not have C4A or C4B deficiency allele (p = 0.04). During periods when SLE was less active clinically, IgG aCL levels returned to normal in 10/12 patients. Active SLE, rather than null alleles, appeared to be associated with low C4 levels in patients with IgG aCL.
authors.affiliation: Department of Medicine, Louisiana State University Medical Center, New Orleans 70112.
authors.forename: W A
authors.initials: WA
authors.lastname: Wilson
authors.forename: M C
authors.initials: MC
authors.lastname: Perez
authors.forename: J P
authors.initials: JP
authors.lastname: Michalski
authors.forename: P E
authors.initials: PE
authors.lastname: Armatis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001323:Autoantibodies / Q000032:analysis*; D044383:Black People; D002308:Cardiolipins / Q000276:immunology*; D002872:Chromosome Deletion; D003181:Complement C4 / Q000172:deficiency* / Q000235:genetics; D015934:Complement C4a; D015935:Complement C4b; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D008180:Lupus Erythematosus, Systemic / Q000235:genetics / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D001741:Black or African American
chemical_list: D001323:Autoantibodies; D002308:Cardiolipins; D003181:Complement C4; D007074:Immunoglobulin G; D015934:Complement C4a; D015935:Complement C4b