MUSK and thymoma: Based on the antibody profile, clinical presentation, age of onset, and thymic pathology, patients can be divided into several subtypes: MG with anti-AChR antibodies (AChR-MG) of early-onset, late-onset or with thymoma; MG with anti-MuSK antibodies (MuSK-MG); MG with anti-LRP4 antibodies (LRP4-MG); ocular MG; and seronegative MG (1, 4).