title: Severe thyroid-associated orbitopathy in Hashimoto's thyroiditis. Report of 2 cases.
abstract: Thyroid-associated orbitopathy (TAO) is characterized by immune-mediated inflammation of the extraocular muscles surrounding orbital connective tissue and adipose tissue. Severe orbitopathy related to autoimmune thyroid disease often occurs in patients with Grave's disease, but it is rare in patients with Hashimoto's thyroiditis. The pathogenesis of TAO is unclear. Several studies have noted a strong correlation between the levels of antibodies to thyrotropin receptor antibody (TRAb) and TAO in Graves' disease. Mild upper eyelid retraction has been reported to be common in Hashimoto's thyroiditis patients, however severe orbitopathy is rare. We report two cases of severe TAO in patients with Hashimoto's thyroiditis who required systemic glucocorticoid therapy and orbital irradiation to treat the TAO. The activity of the TAO was high in both patients, because their clinical activity scores (CAS) for the orbitopathy were high, and magnetic resonance imaging (MRI) showed enlargement of the extraocular muscles and an increase in T2 signal intensity and prolonged T2 relaxation time which indicate an active stage of inflammation. We tested the presence of TRAb by three different assays and were negative in both patients. Since the eye muscle damage cannot be due to TSH receptor antibodies, other pathogenetic mechanisms may be responsible for the orbitopathy in patients with Hashimoto's thyroiditis.
authors.affiliation: Ito Hospital, Tokyo 150-8308, Japan. a-yoshihara@ex.ito-hospital.jp
authors.forename: Ai
authors.initials: A
authors.lastname: Yoshihara
authors.forename: Jaeduk
authors.initials: J
authors.lastname: Yoshimura Noh
authors.forename: Ayako
authors.initials: A
authors.lastname: Nakachi
authors.forename: Hidemi
authors.initials: H
authors.lastname: Ohye
authors.forename: Shiori
authors.initials: S
authors.lastname: Sato
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sekiya
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kosuga
authors.forename: Miho
authors.initials: M
authors.lastname: Suzuki
authors.forename: Masako
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Yo
authors.initials: Y
authors.lastname: Kunii
authors.forename: Natsuko
authors.initials: N
authors.lastname: Watanabe
authors.forename: Koji
authors.initials: K
authors.lastname: Mukasa
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Inoue
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Ito
authors.forename: Koichi
authors.initials: K
authors.lastname: Ito
mesh_terms: D000328:Adult; D005260:Female; D049970:Graves Ophthalmopathy / Q000188:drug therapy / Q000209:etiology* / Q000532:radiotherapy; D050031:Hashimoto Disease / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D009915:Orbit / Q000528:radiation effects; D011241:Prednisone / Q000627:therapeutic use; D013974:Thyroxine / Q000627:therapeutic use
chemical_list: D013974:Thyroxine; D011241:Prednisone; D008775:Methylprednisolone