Thyrotoxic Periodic Paralysis as an Ongoing Diagnostic Challenge: A Case Report and Literature Review

Thyrotoxic periodic paralysis (TPP) is a rare condition that presents with episodic periodic paralysis due to hypokalemia that develops from hyperthyroidism. Timely diagnosis is still an ongoing challenge due to lack of awareness, self-resolving episodes, and the fact that it clinically mimics familial hypokalemic periodic paralysis (FHPP), which is more common in the West. TPP is more commonly seen among Asians but has been emerging in Western countries due to globalization. We present a case of a 24-year-old Hispanic male who presented with bilateral lower extremity weakness. He had five such episodes in the past year, which resolved on their own. The current episode of weakness was worse, and he required a wheelchair to ambulate. Despite extensive work, it took over four months to make a definitive diagnosis and treat his hyperthyroidism. A literature review reported that most cases of TPP are usually diagnosed after multiple episodes, and the causes of diagnostic error were studied. Through this review, we present a case of TPP with diagnostic delay, a literature review discussing the etiology, pathogenesis, clinical manifestations, and management, with an emphasis on the diagnostic challenge of TPP. Awareness of this condition, timely evaluation for hyperthyroidism as a cause for hypokalemic periodic paralysis, and understanding the factors that contribute to its diagnostic challenge will aid in timely recognition and treatment.