A possible association of hypokalaemic periodic paralysis, autoimmune thyroiditis and neuromyotonia

摘要

Acute hypokalemic periodic paralysis (HPP), a clinical syndrome characterised by acute systemic weakness and low serum potassium (K+), is a rare but treatable cause of acute limb weakness. Hypokalemia can be caused by K+ loss via the kidneys or extra renal routes mainly the gut, or due to transcellular potassium shifts where extracellular K+ will move into the cell. In the latter situation, although there is hypokalaemia, there is no deficit of K+ in the body. The main causes for intracellular shift of K+ are familial hypokalemic periodic paralysis, thyrotoxic periodic paralysis, barium poisoning, insulin excess and alkalosis [1]. Although the association between thyrotoxicosis and HPP is known, HPP with hypothyroidism is extremely rare. We report a case of hypokalemic periodic paralysis associated with hypothyroidism and neuromyotonia DOI: http://dx.doi.org/10.4038/cmj.v58i4.6311 Ceylon Medical Journal 2013; 58: 175-176