INTRODUCTION
Pretibial myxedema (PTM) is a rare manifestation of Graves’ disease and less commonly Hashimoto’s thyroiditis. The progression of Graves’ disease usually begins with thyroid dysfunction, followed by thyroid-associated ophthalmopathy (TAO) and then PTM.1 PTM often presents as non-pitting edema with hyperpigmented hyperkeratotic papules and plaques localized to the pretibial region.
Although there are no FDA approved treatments for PTM, topical and intralesional corticosteroids, rituximab, intravenous immunoglobulin, plasmapheresis, octreotide, and pentoxifylline have been used with variable success.1 Recently teprotumumab, an insulin-like growth factor-1 (IGF-1) receptor inhibitor approved for the treatment for TAO, was reported to improve PTM.2,3,4 We present two cases where the use of teprotumumab improved PTM.2,3
Although there are no FDA approved treatments for PTM, topical and intralesional corticosteroids, rituximab, intravenous immunoglobulin, plasmapheresis, octreotide, and pentoxifylline have been used with variable success.1 Recently teprotumumab, an insulin-like growth factor-1 (IGF-1) receptor inhibitor approved for the treatment for TAO, was reported to improve PTM.2,3,4 We present two cases where the use of teprotumumab improved PTM.2,3
CASES
Patient 1
Patient 1 is a 42-year-old female with a history of hyperthyroidism status post radioactive iodine ablation in her teenage years. In 2019, she was diagnosed with Graves’ disease and severe TAO. She was then referred to dermatology in 2020 where firm plaques with plate-like scales were noted on her bilateral lower extremities (Figure 1A), which was biopsied and showed findings consistent with PTM. She was treated with compression, pentoxifylline, and intralesional steroids without improvement. The PTM negatively affected her quality of life making it difficult to ambulate, stand for long periods, and put on shoes. Despite treatment with systemic steroids, radiation therapy to bilateral orbits, and rituximab infusions, her ophthalmopathy and PTM progressed (Figure 1B). Teprotumumab therapy was started for refractory ophthalmopathy in August 2021. She received a shortened course of teprotumumab (five doses) after experiencing intolerable side effects from drug-induced diabetes mellitus. Although she still had remaining plaques, her symptoms of PTM significantly improved by her follow up visit in November 2021 (Figure 1C). Her ophthalmopathy also improved without complete resolution.
Patient 2
Patient 2 is a 55-year-old male with PTM secondary to Graves’ disease. He was first diagnosed with Graves’ disease in 2010 and his thyroid disease was controlled for many years. However, in 2012, he developed edema, nodules, and indurated plaques on the dorsal feet and pretibial lower legs consistent with PTM
Patient 1 is a 42-year-old female with a history of hyperthyroidism status post radioactive iodine ablation in her teenage years. In 2019, she was diagnosed with Graves’ disease and severe TAO. She was then referred to dermatology in 2020 where firm plaques with plate-like scales were noted on her bilateral lower extremities (Figure 1A), which was biopsied and showed findings consistent with PTM. She was treated with compression, pentoxifylline, and intralesional steroids without improvement. The PTM negatively affected her quality of life making it difficult to ambulate, stand for long periods, and put on shoes. Despite treatment with systemic steroids, radiation therapy to bilateral orbits, and rituximab infusions, her ophthalmopathy and PTM progressed (Figure 1B). Teprotumumab therapy was started for refractory ophthalmopathy in August 2021. She received a shortened course of teprotumumab (five doses) after experiencing intolerable side effects from drug-induced diabetes mellitus. Although she still had remaining plaques, her symptoms of PTM significantly improved by her follow up visit in November 2021 (Figure 1C). Her ophthalmopathy also improved without complete resolution.
Patient 2
Patient 2 is a 55-year-old male with PTM secondary to Graves’ disease. He was first diagnosed with Graves’ disease in 2010 and his thyroid disease was controlled for many years. However, in 2012, he developed edema, nodules, and indurated plaques on the dorsal feet and pretibial lower legs consistent with PTM
