Endocrine Abstracts

Thyrotoxic periodic paralysis (TPP) is due to a fall in potassium levels and threat life if it effects respiratory muscles. Men are more effected than women, and lower extremeties are more prone to involvement. Serum potassium in hyperthroidism is usually normal, but Na⁺/K⁺ ATP’ase sensitivity is increased and extracellular potassium rapidly passes to the intracellular space. Beta blockers, small dose potassium replacement and hyperthyroidism treatment blocks this shift and TPP can be treated. Achieving euthyroidism is essential for the cure of TPP. Although hyperthyroidism effects mainly females, TPP is seen more in males especially in the second and fourth decades. Periodic paralysis is seen only in 2% of thyrotoxic patients which is characterized by hypokalemia, proximal muscle weakness and acute onset. We present four cases of male patients aged between 28 and 36 years old. Their complaints were, fatique, weakness and difficuilty in walking. Two patients had known Graves’ disease and two patients were diagnosed as new onset Graves’ disease. They did not have predisposing factors such as alcohol intake, using diuretics or laxatives. On phsical examination, they all had proximal muscle weakness and diminished lower extremity deep tendon reflexes. Their potassium levels were 2.7-2.3-2.1-1.9 mEq/l respectively. Their thyroid antibodies were positive, TSH levels were supressed and free thyroid hormones were elevated. Patients were treated with potassium replacement and antithyroid drugs and lower extremity weakness and paralysis were disappeared. HPP is a genetic disorder but rarely it can be due to thyrotoxicosis. Although TTP is more commonly seen in Graves disease, it is free of disease duration and severity.