title: Autoantibody detection using indirect immunofluorescence on HEp-2 cells.
abstract: The detection of autoantibodies is an important element in the diagnosis and monitoring of disease progression in patients with autoimmune diseases. In laboratory diagnostic tests for connective tissue and autoimmune liver diseases, indirect immunofluorescence on HEp-2 cells plays a central role in a multistage diagnostic process. Despite the high quality of diagnostics, findings at different laboratories can differ considerably due to a lack of standardization, as well as subjective factors. The present paper formulates recommendations for the standardized processing and interpretation of the HEp-2 cell test for the detection of non-organ-specific (especially antinuclear) antibodies. It provides requirements regarding the diagnostic tests used, instructions for laboratory procedure and evaluation, and recommendations for interpretation. For an optimal laboratory diagnostic process, it is useful to have an informative, tentative clinical diagnosis and an experienced laboratory diagnostician. In addition, the following key elements are recommended: initial screening using indirect immunofluorescence on carefully chosen HEp-2 cells beginning with a serum dilution of 1:80 and evaluation under a microscope with powerful illumination; results from a titer of 1:160 upwards being considered positive; internal laboratory quality control; and standardized interpretation. The aim is to improve diagnostic tests and care of patients with autoimmune diseases as a central concern of the European Autoimmunity Standardization Initiative (EASI).
authors.affiliation: Institute of Clinical Immunology and Transfusion Medicine, Medical Faculty of the University, Leipzig, Germany. ulrich.sack@medizin.uni-leipzig.de
authors.forename: Ulrich
authors.initials: U
authors.lastname: Sack
authors.forename: Karsten
authors.initials: K
authors.lastname: Conrad
authors.forename: Elena
authors.initials: E
authors.lastname: Csernok
authors.forename: Ingrid
authors.initials: I
authors.lastname: Frank
authors.forename: Falk
authors.initials: F
authors.lastname: Hiepe
authors.forename: Thorsten
authors.initials: T
authors.lastname: Krieger
authors.forename: Arno
authors.initials: A
authors.lastname: Kromminga
authors.forename: Philipp
authors.initials: P
authors.lastname: von Landenberg
authors.forename: Gerald
authors.initials: G
authors.lastname: Messer
authors.forename: Torsten
authors.initials: T
authors.lastname: Witte
authors.forename: Rudolf
authors.initials: R
authors.lastname: Mierau
mesh_terms: D000974:Antibodies, Antinuclear / Q000097:blood; D001323:Autoantibodies / Q000097:blood*; D045744:Cell Line, Tumor; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods* / Q000592:standards; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results
chemical_list: D000974:Antibodies, Antinuclear; D001323:Autoantibodies