Background: The use of plasma exchange (PE) constituted an advance in the treatment of myasthenia. The objective of our study was to determine the relevance of PE in the treatment of myasthenia and to study the different complications which can be observed during PE.
Patients and methods: We studied retrospectively 11 patients who have generalized myasthenia and underwent PE. We used an intermittent flow cell separator and we performed PE three times a week. Biological assessment was performed before and after PE for all patients. The exchange volume was calculated according to the patient weight, gender and the value of hematocrit.
Results: Our series included six women and five men. The mean age at onset of the disease was 41.4+/-14.1 years (range: 18 to 68). Indication of PE was myasthenia crisis (eight cases), resistance to classic treatment (two cases) and exacerbation after thymectomy (one case). An improvement was observed rapidly in five cases and delayed in three cases. The remaining three patients did not improve. The most frequent side effects of PE were hypotension (four cases), heart arrhythmia (two cases) and hypoglycemia (one case). Three patients dead in the seven days after the first PE.
Conclusion: PE represents an interesting tool to treat severe forms of myasthenia and improve prognosis. High incidence of complications in our series can be explained by the initial disease severity, the used method of PE, the existence of associated illness, and a long stay in intensive care unit.