[Cholinergic crisis in a patient with myasthenia treated by plasma exchange and anticholinesterase agents].

A patient with myasthenia receiving treatment with anticholinesterase agents and plasma exchanges for an acute episode, developed three successive periods of neurological deterioration during which plasma cholinesterase levels were determined. The risk of onset of a cholinergic crisis under these circumstances has been reported in the literature but not documented. The accidents in the present case were related to cumulative overdose effects of anticholinesterase agents and depletion of cholinesterase, suggesting caution in the use of anticholinesterase agents when frequent plasma exchanges are being carried out in a patient with myasthenia.