title: Thyroid ultrasonography in patients with a previous episode of amiodarone induced thyrotoxicosis.
abstract: Amiodarone induced thyrotoxicosis (AIT) occurs most frequently in euthyroid patients with nodular goiter or Graves' disease due to release of iodine from this iodine rich drug. However, some cases of AIT have been attributed to an inflammatory process of the thyroid gland due to amiodarone itself. We have studied the echographic pattern of the thyroid in 11 euthyroid patients who had an episode of AIT 32.4 +/- 3.6 months earlier due to amiodarone induced thyroiditis. There was a significant increase in dyshomogeneous echo patterns and hyperechogenecity which suggests fibrotic lesions. These findings were similar to those observed in 10 euthyroid patients who 77 +/- 12 months earlier had an episode of subacute thyroiditis (SAT). Thyroid volumes of control subjects and patients with a history of AIT and SAT were 10.9 +/- 1.4, 8.7 +/- 1.4 and 9.8 +/- 1.7, in the order. These values were not significantly different. These echographic findings, normal serum thyroid hormone and TSH concentrations and the absence of circulating antithyroid peroxidase antibodies suggest that underlying thyroid autonomy and Graves' disease were not the cause of the previous episode of AIT. The presence of hyperechogenic and dyshomogeneous patterns appears the result of the healing of the inflammatory AIT process.
authors.affiliation: Cattedra di Endocrinologia, Università di Parma, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Roti
authors.forename: L
authors.initials: L
authors.lastname: Bianconi
authors.forename: F
authors.initials: F
authors.lastname: De Chiara
authors.forename: R
authors.initials: R
authors.lastname: Minelli
authors.forename: C
authors.initials: C
authors.lastname: Tosi
authors.forename: E
authors.initials: E
authors.lastname: Gardini
authors.forename: M
authors.initials: M
authors.lastname: Salvi
authors.forename: L E
authors.initials: LE
authors.lastname: Braverman
mesh_terms: D000328:Adult; D000368:Aged; D000638:Amiodarone / Q000009:adverse effects*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D013971:Thyrotoxicosis / Q000139:chemically induced* / Q000000981:diagnostic imaging*; D014463:Ultrasonography
chemical_list: D000638:Amiodarone