http://informahealthcare.com/psm ISSN: 0091-3847 (print) Phys Sportsmed, 2015; 43(1): 104–105 DOI: 10.1080/00913847.2015.1001715
CASE REPORT
A case report of sudden-onset upper and lower extremity weakness Heba Haddad1 & Michael Rotblatt2 1
Internal Medicine Resident, Olive View–UCLA Medical Center, Sylmar, CA, USA, and Associate Program Director, Chief of the Division of General Internal Medicine Clinical, Professor of Medicine, Olive View-UCLA Medical Center, Sylmar, CA, USA
The Physician and Sportsmedicine Downloaded from informahealthcare.com by Nyu Medical Center on 07/06/15 For personal use only.
2
Abstract
Keywords:
Thyrotoxic hypokalemic periodic paralysis is characterized by acute attacks of muscle paralysis, hypokalemia, and thyrotoxicosis. It is a medical emergency, as fatal and life-threatening ventricular arrhythmia associated with hypokalemia has been reported. A 24-year-old man presented with severe lower extremity weakness, which progressed to his trunk and arms. He denied any associated symptoms and had no history of a similar episode or predisposing condition. The physical examination was significant for bilateral extremity weakness, more severe in the lower as compared to the upper extremities. The rest of the neurologic exam was normal. A small, smooth, nontender goiter was palpated. Laboratory data was significant for a potassium level of 2.0 mEq/L. Final lab data revealed a thyroid panel consistent with hyperthyroidism. Once the patient’s potassium level normalized after repletion, he recovered his strength and was able to walk again. He was diagnosed with thyrotoxic hypokalemic periodic paralysis, a potentially lethal complication of hyperthyroidism. Because it is reversible with treatment of hyperthyroidism, it is imperative that this condition be considered, recognized and managed appropriately.
Hyperthyroidism, potassium chloride repletion, thyrotoxic hypokalemic periodic paralysis, ventricular arrhythmia
Introduction Weakness is a common presenting concern. The causes of weakness can be related to muscle diseases, neuromuscular junction disorders, or problems in the lower and upper motor neurons [1]. A systematic approach, with a thorough history, physical examination, and specialized testing, can help lead to the diagnosis.
Case presentation A 24-year-old man presented to our county hospital with severe lower extremity weakness. Earlier that day, after waking from a nap, the patient’s legs “suddenly gave way,” and he was unable to walk. He was brought to the emergency department (ED) with the help of friends. He was able to move only his upper extremities but was not strong enough to sit. While in the ED, his weakness progressed to his trunk and arms. Three days prior to admission, he had a mild sore throat and congestion that resolved that same day. He denied chest pain, shortness of breath, headache, nausea, vomiting, and diarrhea. There was no history of paralysis, blood clots, head trauma, recent immobility, or surgery. The patient had no past medical history of note, is a 5-pack per year smoker, drinks 10 beers on weekends, and has a history of using cocaine, methamphetamines, and ecstasy, last use 2 years ago. He denied any family history of
History Published online 5 January 2015
intermittent paralysis. He was not taking any prescription or other medications, including steroids. His father is German and his mother is Mexican and Native American. The physical examination was significant for normal vital signs, 3+/5 strength in the upper extremities, 2/5 strength in the lower extremities, and inability to walk. The rest of his neurologic exam was normal including reflexes. A small, smooth, nontender goiter was palpated, with a faint thyroid bruit. Laboratory data obtained in the ED were significant for a potassium level of 2.0 mEq/L. The patient received potassium chloride repletion intravenously and his potassium blood levels rose to normal values after a few attempts at repletion. After potassium normalization, the patient recovered his strength and was able to walk again. Computed tomography of the head was negative for acute bleed or stroke.
Discussion Final lab data revealed a thyroid panel consistent with hyperthyroidism (thyroid-stimulating hormone < 0.008 mIU/, free thyroxine = 3.79 mcg/dL, total triiodothyronine = 2.90 ng/dL). Remarkably, the patient lacked any hyperthyroid symptoms. The patient was diagnosed with thyrotoxic hypokalemic periodic paralysis (THPP), the most common form of hypokalemic periodic paralysis (HPP). It has a prevalence
Correspondence: Heba Haddad, MD, Olive View–UCLA Medical Center, 14445 Olive View Drive, Sylmar, CA 91342, USA. Fax: +1 818 364 4573. E-mail: [email protected] 2015 Informa UK Ltd.
The Physician and Sportsmedicine Downloaded from informahealthcare.com by Nyu Medical Center on 07/06/15 For personal use only.
DOI: 10.1080/00913847.2015.1001715
of 1 in 100 000, and is seen primarily in Asian males, occurring in 1.9% of Japanese hyperthyroid patients overall and up to 8% of hyperthyroid Japanese men [2]. American Indians are also thought to be at a higher risk of THPP. There is evidence that their ancestors originated in Asia and migrated to North America between 11 000 and 23 000 years ago [3,4]. Despite a much higher incidence of thyrotoxicosis in women, THPP predominantly affects males [5]. (The patient is a mix of German, Mexican and Native American.) Thyrotoxic hypokalemic periodic paralysis is a potentially lethal complication of hyperthyroidism. It is characterized by acute attacks of muscle paralysis, hypokalemia, and thyrotoxicosis. Fatal and life-threatening ventricular arrhythmia associated with hypokalemia has been reported. Muscle paralysis is transient, self-limited, associated with hypokalemia, and resembles hypokalemic periodic paralysis, but it also includes symptoms of thyrotoxicosis. The hyperthyroid symptoms are often quite mild and may be overlooked, as was the case with this patient [2]. Patients with THPP usually experience the attack a few hours after a heavy meal or in the early morning upon waking; more than two thirds of patients present to the ED between 9 PM and 9 AM. Because of this timing of presentation, the condition was initially described as nocturnal paralysis or night palsy [5]. The degree of hypokalemia is correlated with the severity of paralysis but not with the clinical features of thyrotoxicosis or thyroid hormone levels [6]. Any cause of hyperthyroidism can be associated with THPP, but Graves’ disease is the most common. Hypokalemia occurs due to a massive shift of potassium into the cells rather than net loss from the body. Excess thyroid hormone may predispose to paralytic episodes by increasing the susceptibility of epinephrine or insulin, and therefore increasing Na-K–adenosine triphosphatase activity in the b-adrenergic receptors of skeletal muscles, leading to potassium shift into the cells [7]. It appears that patients with THPP have an underlying predisposition for activation of Na-K–adenosine triphosphatase activity, either directly by thyroid hormone or indirectly via adrenergic stimulation, insulin, or exercise [5]. Because failure to properly diagnose and treat THPP can be fatal, rapid correction of potassium abnormalities is imperative, as it can resolve the symptoms quickly and completely. This can be achieved with potassium chloride IV or PO preparations, or both. A few case reports found that IV propranolol rapidly reversed the paralysis in patients with THPP who failed to respond to potassium replacement [8]. In view of the small number of case reports on the use of b-blockers alone, more controlled studies are needed to determine their efficacy, compared with that of potassium supplementation in the emergency treatment of THPP.
Sudden-onset upper and lower extremity weakness
105
Fortunately, THPP is reversible with treatment of hyperthyroidism. Before achieving euthyroid status, the rate of recurrent attacks is reported to be as high as 62.2%, peaking in the first 3 months after THPP diagnosis [9]. Treatment of hyperthyroidism can be achieved by either (1) medical therapy with antithyroid drugs and nonselective b-blockers or radioactive iodine, or (2) surgery (thyroidectomy or subtotal thyroidectomy) [6]. Prophylactic potassium therapy has not been shown to prevent attacks; in fact, it can predispose to dangerous levels of hyperkalemia [10].
Conclusion Thyrotoxic hypokalemic periodic paralysis is a medical emergency, as it is a potentially lethal complication of hyperthyroidism. It should be included in the differential diagnosis of muscle weakness, even if the patient does not have overt signs and symptoms of hyperthyroidism. Despite its known prevalence in Asian men, with the current ease of traveling and mixing of cultures, THPP should be suspected in patients of all ethnicities.
Declaration of interest H. Haddad, MD, and M. Rotblatt, MD, PharmD, have no conflicts of interest to declare.
References [1] Reeves A, Swenson R. Disorders of the Nervous System. 3rd ed. Gardena, CA: Imperial Company Printers; 1995. [2] Soule B, Simone N. Hypokalemic periodic paralysis: a case report and review of the literature. Cases J 2008;1:256. [3] Layzer RB. Neuromuscular manifestation of endocrine disease. In Becker KL, ed. Principles and Practice of Endocrinology and Metabolism. Philadelphia, PA: JB Lippincott; 1990. 1536. [4] Jones PN. American Indian mtDNA, Y Chromosome Genetic Data, and the Peopling of North America. Boulder, CO: Bauu Institute; 2004. [5] Kung A. Thyrotoxic periodic paralysis: a diagnostic challenge. J Clin Endocrinol Metab 2006;91:2490–5. [6] Loh KC, Pinheiro L, Ng KS. Thyrotoxic period paralysis complicated by near-fatal ventricular arrhythmias. Singapore Med J 2005;46:88–9. [7] Lin Y, Wu CW, Chen HC, et al. Surgical treatment for thyrotoxic hypokalemic periodic paralysis: case report. World J Surg Oncol 2012;10:21. [8] Birkhahn RH, Gaeta TJ, Melniker L. Thyrotoxic periodic paralysis and intravenous propranolol in the emergency setting. J Emerg Med 2000;18:199–202. [9] Hsieh MJ, Lyu RK, Chang WN, et al. Hypokalemic thyrotoxic periodic paralysis: clinical characteristics and predictors of recurrent paralytic attacks. Eur J Neurol 2008;15:559–64. [10] Silva MR, et al. Thyrotoxic hypokalemic periodic paralysis, an endocrine emergency: clinical and genetic features in 25 patients. Arq Bras Endocrinol Metab 2004;48:196–215.
CASE REPORT
A case report of sudden-onset upper and lower extremity weakness Heba Haddad1 & Michael Rotblatt2 1
Internal Medicine Resident, Olive View–UCLA Medical Center, Sylmar, CA, USA, and Associate Program Director, Chief of the Division of General Internal Medicine Clinical, Professor of Medicine, Olive View-UCLA Medical Center, Sylmar, CA, USA
The Physician and Sportsmedicine Downloaded from informahealthcare.com by Nyu Medical Center on 07/06/15 For personal use only.
2
Abstract
Keywords:
Thyrotoxic hypokalemic periodic paralysis is characterized by acute attacks of muscle paralysis, hypokalemia, and thyrotoxicosis. It is a medical emergency, as fatal and life-threatening ventricular arrhythmia associated with hypokalemia has been reported. A 24-year-old man presented with severe lower extremity weakness, which progressed to his trunk and arms. He denied any associated symptoms and had no history of a similar episode or predisposing condition. The physical examination was significant for bilateral extremity weakness, more severe in the lower as compared to the upper extremities. The rest of the neurologic exam was normal. A small, smooth, nontender goiter was palpated. Laboratory data was significant for a potassium level of 2.0 mEq/L. Final lab data revealed a thyroid panel consistent with hyperthyroidism. Once the patient’s potassium level normalized after repletion, he recovered his strength and was able to walk again. He was diagnosed with thyrotoxic hypokalemic periodic paralysis, a potentially lethal complication of hyperthyroidism. Because it is reversible with treatment of hyperthyroidism, it is imperative that this condition be considered, recognized and managed appropriately.
Hyperthyroidism, potassium chloride repletion, thyrotoxic hypokalemic periodic paralysis, ventricular arrhythmia
Introduction Weakness is a common presenting concern. The causes of weakness can be related to muscle diseases, neuromuscular junction disorders, or problems in the lower and upper motor neurons [1]. A systematic approach, with a thorough history, physical examination, and specialized testing, can help lead to the diagnosis.
Case presentation A 24-year-old man presented to our county hospital with severe lower extremity weakness. Earlier that day, after waking from a nap, the patient’s legs “suddenly gave way,” and he was unable to walk. He was brought to the emergency department (ED) with the help of friends. He was able to move only his upper extremities but was not strong enough to sit. While in the ED, his weakness progressed to his trunk and arms. Three days prior to admission, he had a mild sore throat and congestion that resolved that same day. He denied chest pain, shortness of breath, headache, nausea, vomiting, and diarrhea. There was no history of paralysis, blood clots, head trauma, recent immobility, or surgery. The patient had no past medical history of note, is a 5-pack per year smoker, drinks 10 beers on weekends, and has a history of using cocaine, methamphetamines, and ecstasy, last use 2 years ago. He denied any family history of
History Published online 5 January 2015
intermittent paralysis. He was not taking any prescription or other medications, including steroids. His father is German and his mother is Mexican and Native American. The physical examination was significant for normal vital signs, 3+/5 strength in the upper extremities, 2/5 strength in the lower extremities, and inability to walk. The rest of his neurologic exam was normal including reflexes. A small, smooth, nontender goiter was palpated, with a faint thyroid bruit. Laboratory data obtained in the ED were significant for a potassium level of 2.0 mEq/L. The patient received potassium chloride repletion intravenously and his potassium blood levels rose to normal values after a few attempts at repletion. After potassium normalization, the patient recovered his strength and was able to walk again. Computed tomography of the head was negative for acute bleed or stroke.
Discussion Final lab data revealed a thyroid panel consistent with hyperthyroidism (thyroid-stimulating hormone < 0.008 mIU/, free thyroxine = 3.79 mcg/dL, total triiodothyronine = 2.90 ng/dL). Remarkably, the patient lacked any hyperthyroid symptoms. The patient was diagnosed with thyrotoxic hypokalemic periodic paralysis (THPP), the most common form of hypokalemic periodic paralysis (HPP). It has a prevalence
Correspondence: Heba Haddad, MD, Olive View–UCLA Medical Center, 14445 Olive View Drive, Sylmar, CA 91342, USA. Fax: +1 818 364 4573. E-mail: [email protected] 2015 Informa UK Ltd.
The Physician and Sportsmedicine Downloaded from informahealthcare.com by Nyu Medical Center on 07/06/15 For personal use only.
DOI: 10.1080/00913847.2015.1001715
of 1 in 100 000, and is seen primarily in Asian males, occurring in 1.9% of Japanese hyperthyroid patients overall and up to 8% of hyperthyroid Japanese men [2]. American Indians are also thought to be at a higher risk of THPP. There is evidence that their ancestors originated in Asia and migrated to North America between 11 000 and 23 000 years ago [3,4]. Despite a much higher incidence of thyrotoxicosis in women, THPP predominantly affects males [5]. (The patient is a mix of German, Mexican and Native American.) Thyrotoxic hypokalemic periodic paralysis is a potentially lethal complication of hyperthyroidism. It is characterized by acute attacks of muscle paralysis, hypokalemia, and thyrotoxicosis. Fatal and life-threatening ventricular arrhythmia associated with hypokalemia has been reported. Muscle paralysis is transient, self-limited, associated with hypokalemia, and resembles hypokalemic periodic paralysis, but it also includes symptoms of thyrotoxicosis. The hyperthyroid symptoms are often quite mild and may be overlooked, as was the case with this patient [2]. Patients with THPP usually experience the attack a few hours after a heavy meal or in the early morning upon waking; more than two thirds of patients present to the ED between 9 PM and 9 AM. Because of this timing of presentation, the condition was initially described as nocturnal paralysis or night palsy [5]. The degree of hypokalemia is correlated with the severity of paralysis but not with the clinical features of thyrotoxicosis or thyroid hormone levels [6]. Any cause of hyperthyroidism can be associated with THPP, but Graves’ disease is the most common. Hypokalemia occurs due to a massive shift of potassium into the cells rather than net loss from the body. Excess thyroid hormone may predispose to paralytic episodes by increasing the susceptibility of epinephrine or insulin, and therefore increasing Na-K–adenosine triphosphatase activity in the b-adrenergic receptors of skeletal muscles, leading to potassium shift into the cells [7]. It appears that patients with THPP have an underlying predisposition for activation of Na-K–adenosine triphosphatase activity, either directly by thyroid hormone or indirectly via adrenergic stimulation, insulin, or exercise [5]. Because failure to properly diagnose and treat THPP can be fatal, rapid correction of potassium abnormalities is imperative, as it can resolve the symptoms quickly and completely. This can be achieved with potassium chloride IV or PO preparations, or both. A few case reports found that IV propranolol rapidly reversed the paralysis in patients with THPP who failed to respond to potassium replacement [8]. In view of the small number of case reports on the use of b-blockers alone, more controlled studies are needed to determine their efficacy, compared with that of potassium supplementation in the emergency treatment of THPP.
Sudden-onset upper and lower extremity weakness
105
Fortunately, THPP is reversible with treatment of hyperthyroidism. Before achieving euthyroid status, the rate of recurrent attacks is reported to be as high as 62.2%, peaking in the first 3 months after THPP diagnosis [9]. Treatment of hyperthyroidism can be achieved by either (1) medical therapy with antithyroid drugs and nonselective b-blockers or radioactive iodine, or (2) surgery (thyroidectomy or subtotal thyroidectomy) [6]. Prophylactic potassium therapy has not been shown to prevent attacks; in fact, it can predispose to dangerous levels of hyperkalemia [10].
Conclusion Thyrotoxic hypokalemic periodic paralysis is a medical emergency, as it is a potentially lethal complication of hyperthyroidism. It should be included in the differential diagnosis of muscle weakness, even if the patient does not have overt signs and symptoms of hyperthyroidism. Despite its known prevalence in Asian men, with the current ease of traveling and mixing of cultures, THPP should be suspected in patients of all ethnicities.
Declaration of interest H. Haddad, MD, and M. Rotblatt, MD, PharmD, have no conflicts of interest to declare.
References [1] Reeves A, Swenson R. Disorders of the Nervous System. 3rd ed. Gardena, CA: Imperial Company Printers; 1995. [2] Soule B, Simone N. Hypokalemic periodic paralysis: a case report and review of the literature. Cases J 2008;1:256. [3] Layzer RB. Neuromuscular manifestation of endocrine disease. In Becker KL, ed. Principles and Practice of Endocrinology and Metabolism. Philadelphia, PA: JB Lippincott; 1990. 1536. [4] Jones PN. American Indian mtDNA, Y Chromosome Genetic Data, and the Peopling of North America. Boulder, CO: Bauu Institute; 2004. [5] Kung A. Thyrotoxic periodic paralysis: a diagnostic challenge. J Clin Endocrinol Metab 2006;91:2490–5. [6] Loh KC, Pinheiro L, Ng KS. Thyrotoxic period paralysis complicated by near-fatal ventricular arrhythmias. Singapore Med J 2005;46:88–9. [7] Lin Y, Wu CW, Chen HC, et al. Surgical treatment for thyrotoxic hypokalemic periodic paralysis: case report. World J Surg Oncol 2012;10:21. [8] Birkhahn RH, Gaeta TJ, Melniker L. Thyrotoxic periodic paralysis and intravenous propranolol in the emergency setting. J Emerg Med 2000;18:199–202. [9] Hsieh MJ, Lyu RK, Chang WN, et al. Hypokalemic thyrotoxic periodic paralysis: clinical characteristics and predictors of recurrent paralytic attacks. Eur J Neurol 2008;15:559–64. [10] Silva MR, et al. Thyrotoxic hypokalemic periodic paralysis, an endocrine emergency: clinical and genetic features in 25 patients. Arq Bras Endocrinol Metab 2004;48:196–215.
