The Japanese clinical guidelines 2022 for myasthenia gravis and Lambert–Eaton myasthenic syndrome

Abstract

The revised Japanese clinical guidelines for myasthenia gravis (MG) and Lambert–Eaton myasthenic syndrome (LEMS) were published in 2022. The notable points in these guidelines (GLs) are as follows: (i) these are the first Japanese GLs to include a description of LEMS; (ii) diagnostic criteria of MG are revised to lessen the incidence of false negative patients; (iii) MG is divided into six clinical subtypes; (iv) a high-dose oral steroid regimen with escalation and de-escalation schedule is not recommended by the GLs; (v) the GLs promote the early fast-acting treatment strategy initially proposed in the previous GLs; (vi) refractory MG is defined; (vii) the use of molecular targeted drugs is included; (viii) diagnostic criteria of LEMS are proposed; and (ix) treatment algorithms for both MG and LEMS are presented. These new GLs are expected to improve the patients' quality of life and will serve to bridge the present era with the molecular targeted treatment eras.