RESUMEN
OBJECTIVES: Autoantibodies directed against cytosolic 5'-nucleotidase 1A have been identified in many patients with inclusion body myositis. This retrospective study investigated the association between anticytosolic 5'-nucleotidase 1A antibody status and clinical, serological and histopathological features to explore the utility of this antibody to identify inclusion body myositis subgroups and to predict prognosis. MATERIALS AND METHODS: Data from various European inclusion body myositis registries were pooled. Anticytosolic 5'-nucleotidase 1A status was determined by an established ELISA technique. Cases were stratified according to antibody status and comparisons made. Survival and mobility aid requirement analyses were performed using Kaplan-Meier curves and Cox proportional hazards regression. RESULTS: Data from 311 patients were available for analysis; 102 (33%) had anticytosolic 5'-nucleotidase 1A antibodies. Antibody-positive patients had a higher adjusted mortality risk (HR 1.89, 95% CI 1.11 to 3.21, p=0.019), lower frequency of proximal upper limb weakness at disease onset (8% vs 23%, adjusted OR 0.29, 95% CI 0.12 to 0.68, p=0.005) and an increased prevalence of excess of cytochrome oxidase deficient fibres on muscle biopsy analysis (87% vs 72%, adjusted OR 2.80, 95% CI 1.17 to 6.66, p=0.020), compared with antibody-negative patients. INTERPRETATION: Differences were observed in clinical and histopathological features between anticytosolic 5'-nucleotidase 1A antibody positive and negative patients with inclusion body myositis, and antibody-positive patients had a higher adjusted mortality risk. Stratification of inclusion body myositis by anticytosolic 5'-nucleotidase 1A antibody status may be useful, potentially highlighting a distinct inclusion body myositis subtype with a more severe phenotype.
Asunto(s)
5'-Nucleotidasa/inmunología , Autoanticuerpos/sangre , Fibras Musculares Esqueléticas/patología , Miositis por Cuerpos de Inclusión/sangre , Miositis por Cuerpos de Inclusión/diagnóstico , Edad de Inicio , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Citosol , Complejo IV de Transporte de Electrones/análisis , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Fibras Musculares Esqueléticas/química , Debilidad Muscular/etiología , Miositis por Cuerpos de Inclusión/patología , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Dispositivos de Autoayuda/estadística & datos numéricos , Tasa de Supervivencia , Factores de TiempoRESUMEN
The authors recruited 19 nonambulant patients with Guillain-Barré syndrome into a pilot, double-blind, randomized, placebo-controlled safety trial of interferon beta 1a (IFN[beta]-1a) (Rebif). Participants received IFN[beta]-1a or placebo subcutaneously three times weekly, 22 microg for the first week and then 44 microg for up to 24 weeks, in addition to IV immunoglobulin (IVIg). IFN[beta] did not have any unexpected interaction with IVIg and there was no significant difference in rate of improvement.
