title: Effectiveness of different methods for anti-Sm antibody identification. A multicentre study.
abstract: Methods for the measurement of autoantibodies frequently provide controversial results. The objective of the present study was to evaluate the performance of Spanish Clinical Laboratories in the measurement of anti-Sm antibodies. A total of 23 laboratories participated, analysing 30 serum samples from patients with systemic lupus erythematosus and other autoimmune and non-autoimmune diseases. The laboratories used four extractable nuclear antigen screens, eight enzyme-linked immunosorbent assays (ELISAs) specific for anti-Sm, one line-blot, one dot-blot and one double immunodiffusion assay, from 15 different manufacturers. A total of 871 results were obtained. In general, very good sensitivity was obtained (95-100%), but specificity was moderate (52-86%) and must be improved. Most ELISAs and the line-blot were valid assays for anti-Sm detection and could serve as tests both for analysis and/or confirmation. The likelihood ratios indicated that both methods can be considered very useful or useful for the determination of anti-Sm antibodies. Nevertheless, the analytical quality of the methods for the measurement of anti-Sm antibodies could probably be improved by standardisation of the methods and the participation of laboratories in external quality control programs.
authors.affiliation: Servicio de Análisis Clínicos, Hospital de Móstoles, Madrid, Spain.
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Llorente
authors.forename: Juana
authors.initials: J
authors.lastname: Jiménez
authors.forename: Concepción
authors.initials: C
authors.lastname: González
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Alarcón
authors.forename: Monserrat
authors.initials: M
authors.lastname: Alsina
authors.forename: Luisa María
authors.initials: LM
authors.lastname: Casas
authors.forename: José Enrique
authors.initials: JE
authors.lastname: Benedito
authors.forename: José
authors.initials: J
authors.lastname: Luis Araquistain
authors.forename: Victor
authors.initials: V
authors.lastname: Farre
authors.forename: José Manuel
authors.initials: JM
authors.lastname: González-Buitrago
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000974:Antibodies, Antinuclear / Q000097:blood*; D000918:Antibody Specificity; D001324:Autoantigens; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D015151:Immunoblotting / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D005779:Immunodiffusion / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D007753:Laboratories; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011786:Quality Control; D017411:Ribonucleoproteins, Small Nuclear / Q000276:immunology*; D013030:Spain; D055517:snRNP Core Proteins
chemical_list: D000974:Antibodies, Antinuclear; D001324:Autoantigens; D017411:Ribonucleoproteins, Small Nuclear; D055517:snRNP Core Proteins