Lingual and Mediastinal Ectopic Thyroid with No Normal Thyroid Gland – A Very Rare Occurrence

Abstract

Introduction
 Ectopic thyroid is a rare congenital condition. Dual ectopic thyroid is rarer still with only 30 cases reported in literature. The most common location is the lingual or sublingual region followed by the hyoid region. Instances of dual ectopic thyroid with one in lingual region and the other in mediastinum are very few.
 Case Report
 A case of dual ectopic thyroid is presented with absent normal thyroid in a girl of 14 years who presented with difficulty in swallowing and lump sensation in throat. Ultrasound, MRI scan and Technetium 99m pertechnetate thyroid scan were done. She showed lingual thyroid and thyroid tissue in upper mediastinum and no thyroid tissue in the normal anatomical location. 
 Discussion
 The discovery of mediastinal ectopic thyroid was incidental. She had subclinical hypothyroidism and was treated with thyroxine replacement therapy.