[Usefulness of plasmapheresis before thymectomy in the management of myasthenia gravis].

Plasmapheresis (PMP) is effective in some clinical situations of myasthenia gravis (MG). To evaluate its usefulness before thymectomy in patients with moderate generalized MG with no respiratory involvement, we studied 24 patients with MG divided into 2 groups of 12. PMP was performed before thymectomy in one group. The course of disease and mean doses of drugs required were recorded over a follow-up period of 12 months. There were no significant differences between the 2 groups in clinical condition or mean dose of anticholinesterase agents before or after thymectomy. Significantly higher doses of corticosteroids were used after the third month of follow-up in the group treated with PMP. We conclude that PMP confers no benefit when applied before thymectomy in patients without severe MG.