Thyrotoxic periodic paralysis in a Hispanic man after the administration of prednisone.
OBJECTIVE
To present a case of thyrotoxic periodic paralysis (TPP) in a Hispanic man and to discuss the potential precipitating mechanisms.


METHODS
We review the clinical and laboratory findings relative to the occurrence of TPP in a 34-year-old Hispanic man, who had been diagnosed as having Graves' disease.


RESULTS
TPP is a rare complication of thyrotoxicosis. The two known triggers of TPP are high carbohydrate intake and rest after strenuous physical activity. Other precipitating factors include ingestion of alcohol, infection, trauma, emotional stress, and exposure to cold. Nonselective beta-adrenergic blocking agents are used as prophylaxis for the paralytic attacks. Glucocorticoids have been used to treat nonresponsive and recurrent episodes. Nevertheless, our patient, a 34-year-old Hispanic man, had received propranolol for 7 days and one single dose of prednisone 2 hours before the onset of the paralysis. In patients with TPP, the Na+/K+-adenosinetriphosphatase (ATPase) pump activity is considerably increased by excess thyroid hormones, resulting in an increased intracellular potassium shift. Insulin activates the Na+/K+-ATPase pump as well; thus, the precipitating effect of a high carbohydrate diet is explained. Glucocorticoids have been shown to increase the number of Na+/K+-ATPase molecules in skeletal muscle. They also increase insulin secretion in the basal state and the first-phase insulin release after a glucose load.


CONCLUSIONS
In our patient with TPP, the onset of the attack was not prevented by the use of propranolol and was likely triggered by the administration of prednisone.
Liu
Zhao
Z
Section of Endocrinology, Diabetes and Nutrition, Boston Medical Center, Boston, Massachusetts 02118, USA.
Braverman
Lewis E
LE
Malabanan
Alan
A
D000328:Adult; D006111:Graves Disease / Q000150:complications / Q000188:drug therapy; D006801:Humans; D020514:Hypokalemic Periodic Paralysis / Q000139:chemically induced* / Q000150:complications; D008297:Male; D011241:Prednisone / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D011433:Propranolol / Q000627:therapeutic use; D013971:Thyrotoxicosis / Q000139:chemically induced* / Q000150:complications*
D011433:Propranolol; D011241:Prednisone