Lingual thyroid with severe hypothyroidism: A case report.

Introduction Ectopic thyroid tissue presenting at the base of the tongue, called lingual thyroid, is a clinical rarity. Clinical presentation varies depending upon either the severity of regional symptoms associated with the enlargement of gland size, or the features related to thyroid dysfunction. Patient concerns We reported a case of a 29-year-old female who presented with symptoms of easy fatigue and depression for 3 months. Diagnosis After a series of diagnostic workup, the lingual thyroid with severe hypothyroidism was diagnosed. Intervention and outcome She received conservative treatment with thyroid hormone replacement and the symptoms improved significantly. Lessons Lingual thyroid is a rare entity that needs careful diagnostic workup including clinical examination, biochemical tests, imaging methods such as ultrasonography, scintigraphy, computed tomography, magnetic resonance imaging, and fine-needle aspiration cytology to plan the management. Lingual thyroid with hypothyroidism and no neck regional symptoms can be conservatively treated and requires regular follow-up for the prevention of potential risk of malignant transformation.