Thyrotoxic periodic paralysis: correct hypokalemia with caution

Area of Science:

• Endocrinology
• Neurology
• Genetics

Background:

• Thyrotoxic periodic paralysis (TPP) is a rare condition, disproportionately affecting East Asian males with thyrotoxicosis.
• It presents as acute hypokalemia and proximal muscle weakness, often triggered by carbohydrate intake or exercise.
• Distinguishing TPP from familial hypokalemic periodic paralysis is crucial for appropriate management.

Observation:

• A case report details a 36-year-old Filipino man with Graves disease presenting with TPP.
• This case highlights the risk of over-administering intravenous potassium due to misinterpreting hypokalemia.
• Total body potassium levels are typically normal in TPP, necessitating careful correction strategies.

Findings:

• Checking thyroid function is vital in patients with acute paralysis, particularly those of Asian descent.
• Administering potassium (<50 mmol) with cardiac monitoring in TPP can mitigate dysrhythmia risks.
• Non-selective beta-blockers are beneficial until euthyroidism is achieved.

Implications:

• Unlike familial periodic paralysis, oral potassium supplementation is ineffective for TPP.
• Acetazolamide can precipitate TPP attacks, contrasting with its use in familial forms.
• Awareness and prompt diagnosis of TPP are essential for preventing complications and guiding treatment.