Rare cause of thyroid enlargement: Localized AA amyloid goiter - A case report

Amyloidosis is extracellular deposition of fibrillary amyloid proteins in various organs. Amyloid infiltration in thyroid is common; however, the occurrence of clinically enlarged thyroid, subsequently leading to goiter, is a rare phenomenon.

36 years old female presented to our OPD with multinodular goiter. She subsequently underwent total thyroidectomy. Thyroidectomy specimen revealed amyloid deposition with characteristic congophilia and birefringence. Further evaluation revealed it to be AA amyloidosis. There were no features of systemic amyloidosis.

Amyloidosis is classified on the type of amyloid protein. Treatment of individual types of amyloidosis is diverse, and hence identification of the protein subtype is paramount.

AA amyloidosis localized primarily to thyroid is infrequent, as it usually occurs with chronic inflammatory conditions or infections. Currently, there are no guidelines for the treatment of localized AA amyloid goiter. We have evidence demonstrating the successful treatment of such a condition with no recurrence noted.