Thyrotoxic Periodic Paralysis: Acute Paralysis as the Initial Presentation of Graves’ Disease

Authors

Osadebamwen Osaghae, Department of Medicine, Division of Internal Medicine, Reading Hospital - Tower Health, West Reading, PAFollow
Hafiza Qadeer, Department of Medicine, Division of Endocrinology & Metabolism, Reading Hospital - Tower Health, West Reading, PAFollow
Sapna Sharma, Department of Medicine, Division of Endocrinology & Metabolism, Reading Hospital - Tower Health, West Reading, PAFollow
Vinita Singh, Department of Medicine, Division of Endocrinology & Metabolism, Reading Hospital - Tower Health, West Reading, PAFollow

Document Type

Abstract

Publication Date

9-1-2025

Abstract

Description: Thyrotoxic periodic paralysis (TPP) is a form of hypokalemic paralysis marked by transient muscle weakness. Often triggered by exertion or high-carbohydrate meals, it primarily affects East Asian and middle-aged men and may be the first sign of hyperthyroidism despite the absence of classic symptoms. Case Report: A 35-year-old Haitian man presented with sudden bilateral lower limb weakness preceded by thigh cramps for 3 days. He had no thyroid-related symptoms. Employed in a warehouse, recent staffing shortages led to more exertion. On examination, he was afebrile, hemodynamically stable, with thyromegaly, reduced hip strength, and diminished reflexes. Laboratory tests showed hypokalemia (2.1 mmol/L), elevated creatine kinase, low thyroid-stimulating hormone, high T4/T3, and positive thyroid antibodies. Electrocardiogram showed U waves, and ultrasound confirmed hypervascular thyroid parenchyma. Diagnosed with hypokalemic TPP, he was treated with methimazole and potassium replacement. His potassium normalized, and his symptoms improved. Discussion: TPP, often linked to Graves’ disease, results when excess thyroid hormone overactivates the sodium-potassium ATPase pump in muscle cells, shifting potassium intracellularly and causing paralysis. Epinephrine and insulin exacerbate this shift, explaining why TPP episodes often follow exertion or high-carbohydrate intake. It is more common in men and shows seasonal variation, possibly due to potassium loss in humid climates. The usual lack of hyperthyroid symptoms complicates TPP diagnosis. Patients often show hypokalemia and respective electrocardiogram changes. Management involves cautious potassium replacement to avoid rebound hyperkalemia, while treatment targets the underlying hyperthyroidism. Conclusion: This case underscores the importance of recognizing TPP as a rare but reversible cause of acute paralysis, even in non-Asian populations and those without overt hyperthyroid symptoms. Early diagnosis and treatment are crucial to preventing complications and ensuring patient recovery. Targeting the underlying hyperthyroidism remains essential for long-term management and recurrence prevention.

Publication Title

Endocrine Practice

Volume

31

Issue

9 Supplement

First Page

S50

Last Page

S50

Comments

AACE Annual Meeting 2025 held 2025-05-15 to 2025-05-17 in Orlando, FL, USA.

Recommended Citation

Osaghae, O., Qadeer, H., Sharma, S., & Singh, V. (2025). Thyrotoxic Periodic Paralysis: Acute Paralysis as the Initial Presentation of Graves’ Disease. Endocrine Practice, 31 (9 Supplement), S50-S50. https://doi.org/https://doi.org/10.1016/j.eprac.2025.05.141