title: A Rare Manifestation of Hypothyroid Myopathy: Hoffmann's Syndrome.
abstract: Hypothyroid myopathy is observed frequently and the resolution of the clinical manifestations of myopathy following thyroid hormone replacement is well known. However, a specific subtype of hypothyroid myopathy, Hoffmann's syndrome, characterized by increased muscular mass (pseudohypertrophy), proximal muscle weakness, muscle stiffness and cramps, is rarely reported. Herein, we describe a 34-year-old male who presented with proximal muscle weakness and non-pitting edema of the lower extremities. He initially visited the neurology department where he was suspected of having polymyositis. Additional laboratory evaluation revealed profound autoimmune hypothyroidism and elevated muscle enzymes including creatine kinase. The patient was started on levothyroxine treatment and, subsequently, clinical symptoms and biochemical parameters resolved with the treatment. The present case highlights that hypothyroidism should be considered in the differential diagnosis of musculoskeletal symptoms even in the absence of overt manifestations of hypothyroidism. To our knowledge, this is the first case reported in Korea.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kang Won
authors.initials: KW
authors.lastname: Lee
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea. sunhwanae@gmail.com.
authors.forename: Sun Hwa
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Jin
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Korea.
authors.forename: Byung Jo
authors.initials: BJ
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Sin Gon
authors.initials: SG
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Dong Seop
authors.initials: DS
authors.lastname: Choi
keywords: Creatine kinase; Hypothyroidism; Muscular diseases