Efficiency of different strategies to detect autoantibodies to extractable nuclear antigens.
Autoantibodies to extractable nuclear antigens (anti-ENA) are identified mainly in samples positive for antinuclear antibodies (ANA). Although the method of choice for ANA screening is indirect immunofluorescence (IIF), several techniques are available to detect anti-ENA. The aim of this study was to compare the efficiency of five different strategies to determine anti-ENA. During a 2-year period we screened ANA in 30375 samples with IIF, and the 4475 samples ANA positive were tested for anti-ENA by double immune diffusion screening or fluoroenzymeimmunoassay (Screening FI); anti-ENA specificities were then determined by line immunoassay (LIA) or fluoroenzymeimmunoassay (FI). We compared five strategies that involved FI or LIA identification of anti-ENA with or without prior screening, or an algorithm that combined fluorescence pattern, number of anti-ENA specificities requested by the clinician and ANA dilution titer. One cost unit (CU) was defined as the cost of 1 test of ANA determination. We detected 553 anti-ENA positive samples. The most efficient strategy was the algorithm, at a cost of 3.3 CU per sample processed, the second most efficient strategy was screening plus FI identification (cost=3.8 CU), and the third most efficient strategy was screening plus LIA identification (cost=3.9 CU). The fourth most efficient strategy was FI identification without prior screening (13.3 CU per sample) and the least efficient was LIA identification without prior screening (13.6 CU per sample). In conclusion, an algorithm that combined techniques for detection, ANA titer, fluorescence pattern and number of specificities requested was the most efficient strategy for determining anti-ENA.
Almeida González
Delia
D
Hospital Universitario Ntra. Sra. de la Candelaria, Tenerife, Canary Islands, Spain.
Cabrera de León
Antonio
A
Rodríguez Pérez
María Del Cristo
Mdel C
Brito Díaz
Buenaventura
B
González Hernández
Ana
A
García García
Diego
D
Vázquez Moncholi
Carmen
C
Aguirre Jaime
Armando
A
D000465:Algorithms; D000974:Antibodies, Antinuclear / Q000097:blood* / Q000191:economics; D034961:Antigens, Nuclear / Q000276:immunology; D045744:Cell Line, Tumor; D003362:Cost-Benefit Analysis; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D005779:Immunodiffusion; D009098:Multiphasic Screening; D016036:Seroepidemiologic Studies
D000974:Antibodies, Antinuclear; D034961:Antigens, Nuclear; D000939:Epitopes; C033055:anti-extractable nuclear antigen antibodies