Endocrine Abstracts

A 46 years old gentleman was referred by his GP to cardiology with 3 weeks history of bilateral leg swelling and rash associated with breathlessness and palpitations. He has no other past medical history to note. He smokes 20 cigarettes a day and works as a manager in a window installation company. He was started on diuretics and further investigations were arranged by cardiology. His symptoms persisted with worsening of skin rash. He was reviewed by GP again 1 month later. He had persistent tachycardia, resting hand tremors, weight loss and worsening lumps on his shins. He was referred to the ambulatory clinic for worsening rash and his symptoms. He had a blood test done revealing hyperthyroidism and was eventually referred to Endocrinology. He was seen in the thyroid clinic in January. On examination, he had hand tremors and was tachycardic. He had mild proptosis, lid swelling and marked pretibial myxoedema bilaterally (picture attached) His blood test revealed biochemical hyperthyroidism. TSH was suppressed <0.01 mU/l with T4 and T3 values of 68.6 and 40.6 pmol/l. Thyroid peroxidase antibody and anti-TSH receptor antibody levels were elevated and were 133 IU/ml and 31.2 u/l respectively. He was started on high dose carbimazole 60 mg a day. He noticed an improvement in his thyrotoxic symptoms after starting treatment. He was advised to abstain from smoking in the context of Grave’s orbitopathy and to maintain his compliance with his anti-thyroid medication. He was also referred to the ophthalmology department for further review. He is under regular follow up under the endocrinology team. Pretibial myxoedema is part of the triad of Graves’ disease which includes ophthalmoplegia and thyroid acropachy. It accumulates in the anterior shin area due to glycosaminoglycan accumulation produced by fibroblasts through cytokines stimulation. Majority of patients have high anti-TSH receptor antibodies and some degree of ophthalmoplegia suggesting that antigen-specific T cells may be responsible for initiating the inflammatory response. Most cases of pretibial myxoedema are asymptomatic and are mostly of cosmetic concern. Topical corticosteroids under occlusive dressing may be helpful. This case intends to highlight the rare occurrence of pretibial myxoedema and to raise awareness among general physicians and endocrinologists.