Clinical Characteristics of Double Seropositive Myasthenia Gravis.

Double seropositive myasthenia gravis (DSP-MG) has antibodies positive to both acetylcholine receptor (AChR) antibody and muscle-specific tyrosine kinase (MuSK) antibody. This study aims to delineate the clinical phenotype of DSP-MG and assess the histopathological correlation with thymoma. This is a retrospective case series conducted at a tertiary care hospital in South India between February 2018 and October 2021. We had 13 DSP-MG patients (seven females, mean age 60.77+/-14.24). The presentation was generalized in nine patients, bulbar in three, and ocular in one patient. Multi-detector computed tomography done in 11 patients showed thymoma in five and thymic hyperplasia in one. Four patients underwent thymectomy; histopathology showed Type A, B2 (n = 2), and AB thymomas. All 13 patients improved with anticholinesterases. Nine patients were administered immunosuppressants, three patients were given intravenous immunoglobulin, and a single patient underwent plasmapheresis. Our study shows that DSP-MG is more similar to the clinical phenotype of AChR-MG.