[Clinical and immunological studies on a patient with myasthenia gravis before and after repeated plasma exchange].

A 56-year-old patient with severe acquired myasthenia gravis refractory to conventional therapy underwent a series of plasma exchanges. Three single exchanges did not improve her status. A series of intensive plasma exchanges of 6 liters each on 4 consecutive days reduced her anti-acetylcholine receptor antibodies to one-tenth of the initial value. The reduction was accompanied by an impressive clinical improvement. This study confirms that antibodies can be removed by plasma exchange. It further shows that the clinical improvement appears to be closely related to the quantity of antibodies removed.