[Reversible alterations of peripheral nerve function in thyroid dysfunction (author's transl)].

In 7 patients with hyperthyroidism and 9 patients with hypothyroidism both thve before treatment and after a period of normal thyroid function of at least one year duration. As far as conduction velocity and relative refractory period are concerned there was no difference between hyperthyroid patients and normal persons, whereas in cases of hypothyroidism before treatment the conduction velocity was shown to be significantly reduced; moreover a prolonged relative refractory period and a decline in amplitude of the nerve action potential were found. These alterations of peripheral nerve function, interpreted as evidence of neuropathy, proved to be reversible when the thyroid function returned to normal.