[Thyrotoxic periodic paralysis. Discussion of the role of Na-K-ATPase, apropos of a case].

We report a case of thyrotoxicosis periodic paralysis (TPP), occurring as a complication of a Grave's disease in a 31 year-old Caucasian male. It has been suggested that the membrane Na-K pump was involved in the pathogenesis of this complication. In our patient, before treatment, the activity of erythrocyte Na-K-ATPase was significantly decreased, as compared with healthy subjects (228nmol Pi/mg prot/h versus 298 + 60 nmol Pi/mg prot/h) and went back to normal levels post treatment. The activity of this enzyme seems to be prone to genetics factors as well as environmental ones. This would explain the higher incidence of TPP in male and in asiatic people. However, other reports emphasize the role of Na-K-pump-independent potassium influx, which would be more specific of TPP.