The Specificity, Sensitivity and Clinical Correlation of CBA, RIPA and ELISA in Detecting AChR and MuSK IgG of Myasthenia Gravis

Myasthenia gravis (MG) is a neuromuscular junction (NMJ) disorder mediated by autoantibodies against AChR, MuSK or other autoantigens located at the post synaptic membrane of the neuromuscular junction. Presence of autoantibodies specific for AChR or MuSK can establish diagnosis in conjunction with clinical presentations. In most established guidelines for the diagnosis and treatment of myasthenia gravis, determination of AChR and MuSK antibodies has been recommended. Radioimmunoprecipitation assay (RIPA), enzyme-linked immunosorbent assay (ELISA), and cell-based assay (CBA) are all commercially available and have been adopted for autoantibody detection by most referring neurologists. At present, specificity and sensitivity of these methods have not been compared in large cohorts within a context of stringent quality control. As a consequence, there are no national or international consensus regarding selection of methods and interpretation of results, resulting in challenges to neurologists managing these patients. To this end, the investigators proposed to conduct a multicenter, double-blind, prospective study to compare the sensitivity and specificity of CBA, RIPA and ELISA assays to detect AChR and MuSK antibodies.

Sex

All

Minimum age

1 Year

Maximum age

90 Years

Inclusion Criteria:

* Patients with compatible clinical features of weakness of skeletal muscles, including ptosis, diplopia, dysphonia, dysphagia, or limb weakness.
* Patients need to do the diagnosis of MG, requiring serum autoantibody, electrophysiological, pharmacological neostigmine test, thymic computed tomography (CT) and magnetic resonance imaging (MRI), etc in the diagnostic evaluation of MG.

Exclusion Criteria:

* Patients with uncertain diagnoses or incomplete clinical data for data analysis.
* Patients with abnormal serum samples, such as hemolysis or lipemia, which will affect the detection base value and the final interpretation of CBA, RIPA and ELISA.

• DERIVEDLi Z, Zhang C, Chang T, Zhang X, Yang H, Gao F, Feng J, Liu H, Chen S, Wang L, Yang C, Li H, Pan Y, Palace J, Shi FD; SCREAM Study Investigators. A multicentre, prospective, double-blind study comparing the accuracy of autoantibody diagnostic assays in myasthenia gravis: the SCREAM study. Lancet Reg Health West Pac. 2023 Jul 19;38:100846. doi: 10.1016/j.lanwpc.2023.100846. eCollection 2023 Sep. PMID 37554174