TY - JOUR T1 - Severe proximal myopathy secondary to Hashimoto’s thyroiditis JF - BMJ Case Reports JO - BMJ Case Reports DO - 10.1136/bcr-2019-230427 VL - 12 IS - 7 SP - e230427 AU - William Jervis AU - Najeeb Shah AU - Shiva Kumar Mongolu AU - Thozhukat Sathyapalan Y1 - 2019/07/01 UR - http://casereports.bmj.com/content/12/7/e230427.abstract N2 - Muscular symptoms in hypothyroidism are common, including myalgia, fatigue and cramps; however, a significantly raised creatine kinase and muscle weakness are rare. Differential diagnosis of patients presenting with muscle weakness and a raised creatine kinase is wide, and hypothyroidism is rarely considered. We report this case of a 30-year-old female presenting with proximal muscle weakness as her primary symptom, hypothyroid symptoms of 3-month duration and a significantly raised creatine kinase. After ruling out other causes of a raised creatine kinase, thyroxine replacement was commenced, which led to complete resolution of her proximal weakness, myalgia and normalisation of creatine kinase level. This case illustrates severe proximal myopathy can be secondary to hypothyroidism, symptoms can resolve with thyroxine replacement and emphasises the importance of measuring thyroid function in patients with proximal weakness/myalgia and a significantly raised creatine kinase. ER -