title: Apathetic thyrotoxicosis secondary to atypical subacute thyroiditis.
abstract: OBJECTIVE
  To report a case of apathetic thyrotoxicosis with an etiology of subacute thyroiditis.
  
  
  METHODS
  We describe the patient's clinical findings, laboratory findings, and clinical course.
  
  
  RESULTS
  An 85-year-old woman with no history of thyroid disease presented with severe obtundation and altered mental status. Laboratory testing documented elevated free thyroxine and free triiodothyronine concentrations and a suppressed thyrotropin concentration. Thyroid antibodies were absent. A radioactive iodine study revealed severely diminished uptake, suggestive of thyroiditis. After a short course of steroids, the patient's mental status returned to baseline. Follow-up laboratory testing showed normalizing thyroid function.
  
  
  CONCLUSIONS
  Even in the absence of a history of thyroid disease, we recommend considering thyroid dysfunction in the differential diagnosis of patients who present with altered mental status, particularly in the elderly population.
authors.affiliation: Department of Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA. Alessia.Carluccio@mountsinai.org
authors.forename: Alessia L
authors.initials: AL
authors.lastname: Carluccio
authors.forename: Nina K
authors.initials: NK
authors.lastname: Sundaram
authors.forename: Robert T
authors.initials: RT
authors.lastname: Yanagisawa
authors.forename: Yaron
authors.initials: Y
authors.lastname: Tomer
mesh_terms: D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D013968:Thyroiditis, Subacute / Q000150:complications* / Q000175:diagnosis*; D013971:Thyrotoxicosis / Q000175:diagnosis* / Q000209:etiology*