Myasthenia gravis exacerbation in association with antibody overshoot following plasmapheresis.

INTRODUCTION/AIM: Antibody overshoot following therapeutic plasmapheresis (PLEX) is defined by subsequent increase in antibody to levels exceeding those prior to removal. It has been infrequently described in the past, and its influence on the clinical course of myasthenia gravis (MG) remains unclear.

METHODS

This was a retrospective analysis of five patients with generalized MG treated with PLEX.

RESULTS

All five patients possessed antibodies against acetylcholine receptor (AChR-Ab). After undergoing 3 to 12 PLEX treatment sessions, AChR-Ab titer increased to a median of 1292% of the baseline level. The median interval from the last PLEX session to peak AChR-Ab detection was 6 wk. In four patients, AChR-Ab overshoot was associated with a clinical deterioration.

DISCUSSION: The AChR-Ab overshoot may occur following PLEX. In patients who deteriorate following PLEX treatment, the presence of antibody overshoot may serve as additional guidance for treatment adjustment.