¿Cuándo solicitar los anticuerpos anticitoplasma de neutrófilo?
- Marta García Castro
- Francisco Javier López Longo
- María Dolores Casas
- Irene Díez Merchán
- María Carpena Zafrilla
- Luis Carreño Pérez
ISSN: 1577-3566
Año de publicación: 2008
Volumen: 9
Número: 4
Páginas: 235-239
Tipo: Artículo
Otras publicaciones en: Seminarios de la Fundación Española de Reumatología
Objetivos de desarrollo sostenible
Resumen
Antineutrophil cytoplasmic antibodies (ANCA) are autoantibodies, usually IgG, directed against azurophilic granules in neutrophils and lysosomes in monocyte components. ANCA are found in patients with small-vessel vasculitides but their true role in the pathogenic cascade remains unclear and these autoantibodies are not always related to disease activity. Several studies demonstrate the existence of ANCA in other diseases, such as infections or neoplasia, and in up to 2% of healthy individuals. In these situations, ANCA could be considered as an inflammation epiphenomenon. ANCA are usually detected by indirect immunofluorescence (IIF) on smears of ethanol-fixed human neutrophils that define patterns such as peripheral (P-ANCA), cytoplasmic (C-ANCA) or atypical (A-ANCA). The antigen is subsequently identified by means of enzyme-linked immunosorbent assay (ELISA). The sensitivity and specificity of both techniques depend heavily on the extent of the vasculitides, clinical activity when the test is performed, and the methodology used in IFI or ELISA. The utility of ANCA in the classification, diagnosis and monitoring of disease is controversial. ANCA determination is recommended at regular intervals during follow-up because an increase in these autoantibodies detected by IFI and ELISA anticipates disease reactivation in 58% and 75% of patients, respectively.