[Durable remission attained with plasmapheresis and intravenous immunoglobulin therapy in a patient with acute exacerbation of GVHD-related myasthenia gravis].

A 17-year-old male underwent a second bone marrow transplantation using a 6/8 allele HLA-matched unrelated donor. On day 100 after transplantation, steroid treatment for chronic graft-versus-host disease (GVHD) was started. On day 766, the patient experienced general fatigue, followed by double vision, ptosis, and dysphagia on day 810. Based on the positivity of the acetylcholine receptor antibody and a waning electromyography pattern, he was diagnosed with GVHD-related myasthenia gravis (MG). On day 861, we initiated plasmapheresis (PE), followed by the administration of intravenous immunoglobulin (IVIg) ; this treatment attenuated the bulbar symptoms of MG. Although the steroid treatment was continued, we restarted the administration of tacrolimus. On day 2,739 after transplantation, we stopped the steroid treatment, and the patient remained in remission for MG following the cessation of the steroid treatment on day 2,897. This case suggests that PE followed by IVIg could be an effective therapeutic alternative for MG associated with GVHD.