Thyrotoxic Periodic Paralysis In A Competitive Bodybuilder With Thyrotoxicosis Factitia

Abstract

OBJECTIVE: We report a case of thyrotoxic periodic paralysis (TPP) in a bodybuilder who developed paralysis secondary to thyrotoxicosis factitia (TF) after taking a supplement containing thyroid hormone. Interestingly, the patient had no intrinsic thyroid disease. Prompt recognition of thyrotoxicosis is critical to avoid progression of paralysis and subsequent complications. METHODS: We discuss a 27 year-old body builder who presented after a 3-day bodybuilding competition with sudden upper and lower extremity paralysis. He admitted to taking anabolic steroids, a supplement containing an unknown amount of thyroid hormone for two weeks, and furosemide 40 mg twice daily with near-complete fluid restriction for three days. RESULTS: Laboratory results showed a thyroid-stimulating hormone level of <0.010 mIU/L (0.3–5.8 uIU/mL), normal total T3 level, elevated free T4 level of 3.6 ng/dL (0.8–1.9 ng/mL), and potassium level of 1.9 mEq/L (3.7–5.2 mEq/L). Thyroid peroxidase antibody, thyroid stimulating immunoglobulin and thyroglobulin antibody levels were normal. Thyroid uptake was 1% (8–25%) after administration of I-123 and thyroglobulin level was 9 ng/mL (1.4 – 29.2 ng/mL). The patient was treated withnormal saline infusion, magnesium supplementation and a total of 230 mEq of potassium within 12 hours of hospitalization. Muscle weakness resolved within this time period and potassium level normalized. By the third day of hospitalization free thyroxine level also normalized and TSH improved to 0.1 mIU/L. CONCLUSION: TPP is a rare complication of thyrotoxicosis that should be considered in bodybuilders who are presenting with acute muscle weakness.

Making weight: acute muscle weakness and hypokalaemia exacerbated by thyrotoxicosis factitia in a bodybuilder

“…This man’s presentation with acute severe leg weakness and hypokalaemia was reminiscent of TPP, albeit with Caucasian ethnicity and no apparent history of thyroid disease, until systems review at presentation noted the consumption of thyroid supplements and thyrotoxicosis factitia which had been diagnosed by his general practioner. A description of a similar presentation in a 27-year-old bodybuilder of Hispanic ethnicity published last year was only the eighth ever described of TPP secondary to thyrotoxicosis factitia ( 6 ) and we believe that ours is the first description in a patient of Caucasian ethnicity. Case series suggest that TPP is typically present in the third decade, over 95% of the time in males ( 2 , 6 ), and is much more common in those of Asian ethnicity ( 7 , 8 ).…”

“…A description of a similar presentation in a 27-year-old bodybuilder of Hispanic ethnicity published last year was only the eighth ever described of TPP secondary to thyrotoxicosis factitia (6) and we believe that ours is the first description in a patient of Caucasian ethnicity. Case series suggest that TPP is typically present in the third decade, over 95% of the time in males (2,6), and is much more common in those of Asian ethnicity (7,8). Our patient's presentation was typical, with rapidly progressive symmetrical muscle weakness in both legs, without sensory symptoms or signs, or bowel or bladder dysfunction (6,7).…”

“…Other causes of hypokalaemia such as laxative or diuretic use need to be excluded, even where thyrotoxicosis is present, before TPP can be diagnosed. In particular, diuretic use may be present in bodybuilders with TPP secondary to thyrotoxicosis factitia ( 6 ), but this would be expected to lead to much greater requirements for potassium replacement, as well as an elevated trans-tubular potassium gradient and a positive urinary diuretic screen, none of which were present in our patient. Our patient’s use of clenbuterol, a potent stimulator of the beta-2 adrenergic receptor is likely to have contributed to enhanced skeletal muscle Na-K-ATPase activation and further sequestration of potassium ( 9 ), precipitating his acute presentation.…”

“…Case series suggest that TPP is typically present in the third decade, over 95% of the time in males ( 2 , 6 ), and is much more common in those of Asian ethnicity ( 7 , 8 ). Our patient’s presentation was typical, with rapidly progressive symmetrical muscle weakness in both legs, without sensory symptoms or signs, or bowel or bladder dysfunction ( 6 , 7 ). Rarely, respiratory muscle involvement or ventricular arrhythmias can also occur ( 7 ).…”

An Unusual Presentation of Thyrotoxicosis: Leg Weakness and Hypokalemia in a 21-Year-Old Male

“…This strong predilection that occurs in males showed a possible association between increased testosterone levels and hypokalemic paralysis in patients with hyperthyroidism [ 3 ]. Androgens can increase the expression and activity of the Na+/K+ ATPase, therefore correlating with the severity of hypokalemia [ 11 , 12 ].…”