Chinese Journal of Contemporary Neurology and Neurosurgery (Oct 2016)
Detection and clinical significance of serum autoantibodies in patients with myasthenia gravis
Abstract
Objective To investigate the expressions and clinical significance of serum anti - acetylcholine receptor antibodies (AChR-Ab), anti-Titin antibodies (Titin-Ab), and anti-Ryanodine receptor antibodies (RyR-Ab) in patients with myasthenia gravis (MG). Methods Serum AChR-Ab, Titin-Ab and RyR-Ab were detected with enzyme-linked immunosorbent assay (ELISA) in 182 MG patients, 105 patients of other neurological diseases (OND) and 62 normal controls. Results Serum AChR-Ab, Titin-Ab and RyR-Ab were detected positive respectively in 68.13% (124/182), 64.29% (117/182) and 67.03% (122/182) of patients in MG group. The positive rates of those antibodies in MG group were significantly higher than those in OND group (P = 0.000, for all) and control group (P = 0.000, for all). When 3 antibodies coexisted, the sensitivity in the diagnosis of MG was 41.21%, with 99.40% of specificity. There was no significant difference in the positive rate of serum AChR-Ab, Titin-Ab and RyR-Ab between early-onset MG subgroup and late-onset MG subgroup (P > 0.05, for all). The positive rates of AChR-Ab were significantly higher in MG patients with thymoma than in those without thymoma (P = 0.004). There was no significant difference in the positive rate of Titin-Ab and RyR-Ab between MG with thymoma subgroup and MG without thymoma subgroup (P > 0.05, for all). The prevalence of AChR-Ab in generalized MG (GMG) atients (Ⅱa and Ⅱb) was higher than those in ocular MG (OMG) patients (typeⅠ; P = 0.005, 0.012). There was no significant difference in the positive rate of Titin-Ab and RyR-Ab between GMG subgroup and OMG subgroup (P > 0.05, for all). Conclusions Serum AChR-Ab, Titin-Ab and RyR-Ab can be used as ndicators of the diagnosis of MG. Patients with 3 coexisted positive antibodies are highly suspected as MG. Higher AChR-Ab level in serum of OMG patients indicates the possibility of progressing to GMG. DOI: 10.3969/j.issn.1672-6731.2016.10.007