Fatigue in SLE: diagnostic and pathogenic impact of anti-N-methyl-D-aspartate receptor (NMDAR) autoantibodies.

ObjectivesWe explored the impact of circulating anti-N-methyl-D-aspartate receptor (NMDAR) antibodies on the severity of fatigue in patients with systemic lupus erythematosus (SLE).MethodsSerum samples of 426 patients with SLE were analysed for the presence of antibodies to the NR2 subunit of the NMDAR. In parallel, the severity of fatigue was determined according to the Fatigue Scale for Motor and Cognitive functions questionnaire. In a subgroup of patients with SLE, the hippocampal volume was correlated with the levels of anti-NR2 antibodies. Isolated immunoglobulin G from patients with anti-NR2 antibodies were used for murine immunohistochemical experiments and functional assays on neuro…