Abstract：
BACKGROUND: Rarely, hyperthyroidism will initially present with chronic myopathy characterized by progressive and sometimes fluctuating proximal muscle weakness, along with elevated creatine kinase and myopathic pattern in the electromyogram, mimicking other muscle and neuromuscular junction disorders with poorer prognosis.
METHODS: Here, we present 2 young patients who complained of 1-4 months duration of chronic proximal muscle lower extremity weakness, supported by elevated creatine kinase and myopathic pattern in electromyogram, who later found to have markedly low thyroid-stimulating hormone, high free T3 and free T4, enlarged thyroid gland on ultrasound, and elevated anti-thyroid-stimulating hormone receptor antibody, characteristic of Grave disease.
CONCLUSIONS: Although rare, thyrotoxicosis should always be ruled out in a patient with chronic myopathy because this has better prognosis than other primary muscle conditions presenting similarly.
METHODS: Here, we present 2 young patients who complained of 1-4 months duration of chronic proximal muscle lower extremity weakness, supported by elevated creatine kinase and myopathic pattern in electromyogram, who later found to have markedly low thyroid-stimulating hormone, high free T3 and free T4, enlarged thyroid gland on ultrasound, and elevated anti-thyroid-stimulating hormone receptor antibody, characteristic of Grave disease.
CONCLUSIONS: Although rare, thyrotoxicosis should always be ruled out in a patient with chronic myopathy because this has better prognosis than other primary muscle conditions presenting similarly.
摘要：
背景：很少，甲状腺功能亢进最初会出现慢性肌病，其特征是进行性和有时波动的近端肌无力，随着肌酸激酶升高和肌电图中的肌病模式，模仿其他肌肉和神经肌肉接头疾病，预后较差。
方法：这里，我们介绍了2名年轻患者，他们主诉1-4个月的慢性近端肌肉下肢无力，肌酸激酶升高和肌电图肌病模式支持，后来发现甲状腺刺激激素明显低，高游离T3和游离T4，超声检查甲状腺肿大，抗甲状腺刺激激素受体抗体升高，Grave病的特征。
结论：虽然罕见，慢性肌病患者应始终排除甲状腺毒症,因为与其他表现类似的原发性肌病相比,甲状腺毒症具有更好的预后.
方法：这里，我们介绍了2名年轻患者，他们主诉1-4个月的慢性近端肌肉下肢无力，肌酸激酶升高和肌电图肌病模式支持，后来发现甲状腺刺激激素明显低，高游离T3和游离T4，超声检查甲状腺肿大，抗甲状腺刺激激素受体抗体升高，Grave病的特征。
结论：虽然罕见，慢性肌病患者应始终排除甲状腺毒症,因为与其他表现类似的原发性肌病相比,甲状腺毒症具有更好的预后.
