RT Journal Article SR Electronic T1 Lesson of the month 1: Subacute thyroiditis: a rare cause of fever of unknown origin JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 86 OP 87 DO 10.7861/clinmedicine.17-1-86 VO 17 IS 1 A1 Fatima Amar Bahowairath A1 Nicholas Woodhouse A1 Samir Hussain A1 Mujahid Al Busaidi YR 2017 UL http://www.rcpjournals.org/content/17/1/86.abstract AB Fever of unknown origin (FUO) is sometimes a diagnostic dilemma for clinicians. Endocrine causes reported in the literature include subacute thyroiditis, thyrotoxicosis, adrenal insufficiency and pheochromocytoma. Among these, subacute thyroiditis is often overlooked as it can occasionally lack typical symptoms. This case illustrates the fact that subacute thyroiditis should be considered as a possible cause of fever even if signs and symptoms of hyperthyroidism and thyroid tenderness are absent.