Thyrotoxic Periodic Paralysis: Case Reports and an Up-to-Date Review of the Literature

Abstract

Objectives. To describe 2 cases of thyrotoxic periodic paralysis. Methods. We report of 2 cases of thyrotoxic periodic paralysis in 2 individuals from 2 different backgrounds with emphasis on their presentation and treatment. We also conducted a literature search to put together an update review of thyrotoxic periodic paralysis. Results. A 47-year-old Chinese and 28-year-old Caucasian male presented with profound yet reversible weakness associated with hypokalemia on admission bloods and thyrotoxicosis. Both were given definitive therapy to prevent recurrence of attacks with any future relapse of thyrotoxicosis. Conclusion. Thyrotoxic periodic paralysis (TPP) is a rare but potentially serious complication of thyrotoxicosis resulting in temporary but severe muscle weakness. Recent discovery of a novel mutation in the KCNJ18 gene which codes for an inwardly rectifying potassium channel and is controlled by thyroid hormones may provide greater insight into the pathogenesis of TPP.

Thyrotoxic Hypokalemic Periodic Paralysis: A Case Series from Trinidad, West Indies

“…The increased ß-adrenergic stimulation results in further increased Na+/K+-ATPase activity. Thus, by blunting the hyper-adrenergic state, ßblockers can prevent the attacks of TPP (12,30,33,35,36). This was clearly seen on the initiation of treatment in our patients having reported significant improvement in muscle power.…”

Stroke Mimic: A Case of Unilateral Thyrotoxic Hypokalemic Periodic Paralysis

“…8 Other known triggers include large carbohydrate loads (excess insulin), exercise (excess catecholamines), stress, toxic adenomas, diuretics, fluoroquinolones, aminoglycosides, amiodarone, alcohol, and even licorice. 2,8,9,10 Presentations vary widely from mild, transient, selflimited motor dysfunction to total flaccid paralysis including respiratory muscles. 11,12,13 Bulbar and ocular symptoms have been reported in rare cases; however, it is unclear whether ocular involvement stems from THPP or the thyrotoxicosis.…”

A rare cause of thyrotoxic periodic paralysis: liquorice consumption

“…These channels are responsible for the efflux of potassium in the cell 9 10. Only one publication has reported that liquorice may also be one of the precipitating factors of TPP 1. The clinical symptoms caused by the use of liquorice depends on the 11-β-hydroxysteroid dehydrogenase type 2 (11-β-HSD2)-like activity of glycyrrhetinic and its acid derivative.…”

“…The most common precipitating factors of the disease are a high-carbohydrate diet and exercise 1 2. Some TPP cases with normal potassium levels have also been reported, but diagnosis is difficult and rare 3.…”