Postoperative myasthenic crisis successfully treated with immunoadsorption therapy.

Myasthenia gravis (MG) is an autoimmune disorder characterized by loss of acetylcholine receptors (AChR) due primarily to the production of anti-AChR autoantibodies. We report a case of MG associated with elevated anti-acetylcholine receptor antibody (anti-AChR Ab) and refractory crisis after thymectomy, in which immunoadsorption therapy was used successfully to stabilize myasthenic symptoms and decrease the anti-AChR Ab titer. A 79-year-old woman underwent extended thymectomy under the diagnosis of MG. One day after surgery she suddenly underwent a myasthenic crisis and was successfully resuscitated. Immunoadsorption therapy with a tryptophan-linked polyvinyl alcohol adsorber was performed three times for the purpose of decreasing the anti-AChR antibodies. The anti-AChR Ab titer was reduced by immunoadsorption during each therapy session; however, the level of anti-AChR Ab before immunoadsorption was higher than that of the previous treatment. This case suggests that the absolute serum level of anti-AChR Ab does not always correlate with the severity of the disease. Removal of pathogenic factors, not only anti-AChR Ab but other antibodies with specificities to skeletal muscles or certain components of the complement system, may contribute to effective treatment of myasthenic crisis.