Asymmetric Pre-Malar Swelling as an Unusual Presentation in a Case of Toxic Multinodular Goiter

Abstract

Toxic multinodular goiter (TMNG) and toxic adenoma are among the leading causes of thyrotoxicosis globally, with a rising incidence attributed to iodine-deficient regions. We report the case of a 34-year-old female who presented to the emergency department of our hospital with progressive unilateral facial swelling for 2 months, associated with squinting of the right eye. A thyroid function test revealed a thyroid-stimulating hormone (TSH) level of 0.007 mIU/L. Subsequently, a technetium-99 (Tc-99) thyroid scan revealed bilateral nodular lobes with heterogeneously increased trapping function, and a dominant hot nodule in the left lower pole, suggestive of TMNG. The patient was referred to an endocrinologist at our institute, and started on systemic carbimazole for 3 months. Her symptom improved progressively, and her TSH level increased to 2.18 mIU/L at the end of 3 months of initiating pharmacotherapy. This study explores the clinical presentation, diagnosis, and molecular pathogenesis of TMNG, including a study showing the association of asymmetrical pre-malar swelling with thyroid-associated orbitopathy (TAO), in some cases of TMNG. The diagnosis of TMNG is based on clinical signs, abnormal thyroid function tests, and imaging. However, more research is needed to establish the direct relationship between the pathophysiology of the development of asymmetric pre-malar swelling and TMNG. We conclude that asymmetric pre-malar swelling, as the first and only presentation of subclinical hyperthyroidism, is a rare but documented finding seen in patients with TMNG. We recommend that patients with asymmetric facial swelling be evaluated for thyroid abnormalities.