Impact of likelihood ratios of rheumatoid factor and anti-cyclic citrullinated peptide antibody in clinical diagnosis of rheumatoid arthritis by two available platforms

Background/Objectives: Rheumatoid arthritis (RA) is one of the most prevalent autoimmune diseases, characterized by an articular and extra-articular involvement, where autoantibodies, such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPAs), are important biomarkers fo...

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Detalles Bibliográficos
Autores: Irure Ventura, Juan, Díaz-Toledo García, María, Palazuelos Cayón, Noelia, López Hoyos, Marcos
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/36658
Acceso en línea:https://hdl.handle.net/10902/36658
Access Level:acceso abierto
Palabra clave:Rheumatoid arthritis
Rheumatoid factor
Anti-cyclic citrullinated peptide antibodies
Likelihood ratio
Descripción
Sumario:Background/Objectives: Rheumatoid arthritis (RA) is one of the most prevalent autoimmune diseases, characterized by an articular and extra-articular involvement, where autoantibodies, such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPAs), are important biomarkers for the diagnosis. Autoantibody determination can be carried out using different assays. However, the results obtained are usually expressed in arbitrary units that are not comparable. Therefore, the aim of this study is to improve clinical interpretation of RF and ACPA test results using the likelihood ratio (LR). Methods: RF and ACPA titers were analyzed by turbidimetry and chemiluminescence using Optilite and BIO-FLASH systems, respectively, in 781 samples from patients with RA and in 1970 controls. Results: The higher the antibody titer of RF or ACPA, the higher the LR for RA. The definition of test result interval-specific LR based on predefined specificities for antibody levels provides more information than the use of the cut-off set by the manufacturer for each antibody. Conclusions: The LR for RA increased with an increasing antibody level. In addition, the use of test result interval-specific LR allows better clinical interpretation for RF and ACPA assays compared to the traditional idea of interpreting antibody results in a dichotomous manner, such as negative or positive.