Hypokalaemic periodic paralysis and hyperthyroidism. A case report

The hypokalaemic thyrotoxic periodic paralysis (HTPP) is a rare neuromuscular disorder in hyperthyroid Caucasian patients. We describe the case of a 31-yr-old man suffering from Graves' disease, admitted to Hospital with flaccid quadriplegia. In comparison with those previously reported, this case shows some peculiarities. Neuromuscular symptoms and signs appeared one year after the onset of hyperthyroidism. No HLA haplotype usually associated with HTPP was found. None of the various factors known to be able to trigger paralytic attacks was identified in our patient. We could not induce the typical neuromuscular picture by a provocative test with glucose and insulin administration. No hyperinsulinaemia was demonstrated either in basal condition or after oral glucose tolerance test. On the basis of these findings, the present case emphasizes the possible different pathogenesis of HTPP in Oriental and Caucasian patients.