title: Localized subacute thyroiditis presenting as a painful hot nodule.
abstract: BACKGROUND
  A diagnosis of subacute thyroiditis is readily considered when patients present with a particular set of typical clinical characteristics. Subacute thyroiditis sometimes presents as a solitary cold nodule; however, the presence of a hot nodule in patients with subacute thyroiditis is exceedingly rare.
  
  
  METHODS
  Here, the case of a 57-year-old woman complaining of pain in the left neck and fatigue for two weeks is presented. Physical examination revealed a painful and tender nodule with a diameter of approximately 1.5 cm in the left neck, although all laboratory tests, including white blood cell count, neutrophil percentage, erythrocyte sedimentation rate (ESR), thyroid function, and thyroglobin levels, were normal. A neck ultrasound revealed a hypoechoic mass (1.5 × 0.8 cm) in the left thyroid, and thyroid scintigraphy of the left thyroid with Technetium-99 m (99 m-Tc) demonstrated a focal accumulation of radiotracer. Furthermore, fine-needle aspiration biopsy from the nodule revealed the presence of multinuclear giant cells. The patient was well; there was no cervical mass detected upon palpation following two months of prednisone treatment, and follow-up ultrasound screening and scintigraphy demonstrated the disappearance of the nodule.
  
  
  CONCLUSIONS
  This case, presenting with a localized painful hot nodule, normal thyroid function, normal ESR, and normal serum thyroglobulin levels, is a rare case of subacute thyroiditis, which should be considered during differential diagnosis.
authors.affiliation: Department of Endocrinology and Metabolism, Shanghai Diabetes Institute; Shanghai Clinical Center for Diabetes; Shanghai key Laboratory of Diabetes Mellitus, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China. lilx@sjtu.edu.cn.
authors.forename: Lian-Xi
authors.initials: LX
authors.lastname: Li
authors.forename: Xing
authors.initials: X
authors.lastname: Wu
authors.forename: Bing
authors.initials: B
authors.lastname: Hu
authors.forename: Hui-Zhen
authors.initials: HZ
authors.lastname: Zhang
authors.forename: Han-Kui
authors.initials: HK
authors.lastname: Lu