title: Periodic Paralysis as a New Phenotype of Resistance to Thyroid Hormone Syndrome in a Chinese Male Adult.
abstract: BACKGROUND
  A majority of patients with resistance to thyroid hormone (RTH) are asymptomatic, whereas some patients show signs of hyperthyroidism, or hypothyroidism, or both. Thyrotoxic periodic paralysis is the most common form of acquired periodic paralysis. However, it has not been reported in a patient with RTH up to now.
  
  
  OBJECTIVE
  We evaluated a 36-year-old male patient from China with elevated serum free T4 and free T3 and inappropriately high TSH who presented with periodic paralysis.
  
  
  METHODS
  Clinical, biochemical, and radiological assessments, as well as DNA sequencing, were performed.
  
  
  RESULTS
  The patient's laboratory tests revealed the following: TSH, 6.14 mIU/L (0.27-4.2 mIU/L); free T3, 12.85 pmol/L (2.8-7.1 pmol/L); free T4, 33.62 pmol/L (9.05-25.5 pmol/L); and serum SHBG, 19.4 nmol/L (18.3-54.1 nmol/L). No significant suppression of TSH was observed in the rapid TSH suppression test with somatostatin analogs. Compound muscle action potential after exercise of the patient was reduced by 58%. Sequencing of thyroid hormone receptor genes confirmed a C446S mutation in the THRβ gene.
  
  
  CONCLUSIONS
  This is the first report of periodic paralysis as a new phenotype of RTH syndrome.
authors.affiliation: Departments of Medicine (S.M., Y.J.) and Endocrinology and Metabolism (M.H., H.Y., X.L.), Peking Union Medical College Hospital, 100730 Beijing, China.
authors.forename: Shikun
authors.initials: S
authors.lastname: Ma
authors.affiliation: Departments of Medicine (S.M., Y.J.) and Endocrinology and Metabolism (M.H., H.Y., X.L.), Peking Union Medical College Hospital, 100730 Beijing, China.
authors.forename: Mingming
authors.initials: M
authors.lastname: Hu
authors.affiliation: Departments of Medicine (S.M., Y.J.) and Endocrinology and Metabolism (M.H., H.Y., X.L.), Peking Union Medical College Hospital, 100730 Beijing, China.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Yang
authors.affiliation: Departments of Medicine (S.M., Y.J.) and Endocrinology and Metabolism (M.H., H.Y., X.L.), Peking Union Medical College Hospital, 100730 Beijing, China.
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Lian
authors.affiliation: Departments of Medicine (S.M., Y.J.) and Endocrinology and Metabolism (M.H., H.Y., X.L.), Peking Union Medical College Hospital, 100730 Beijing, China.
authors.forename: Yanqiu
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000328:Adult; D004247:DNA / Q000235:genetics; D006727:Hormone Antagonists / Q000494:pharmacology; D006801:Humans; D008297:Male; D009154:Mutation / Q000235:genetics; D010245:Paralyses, Familial Periodic / Q000235:genetics* / Q000503:physiopathology; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013004:Somatostatin / Q000031:analogs & derivatives / Q000494:pharmacology; D037042:Thyroid Hormone Receptors beta / Q000235:genetics; D018382:Thyroid Hormone Resistance Syndrome / Q000235:genetics* / Q000503:physiopathology; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D006727:Hormone Antagonists; D012738:Sex Hormone-Binding Globulin; D037042:Thyroid Hormone Receptors beta; D014284:Triiodothyronine; D013004:Somatostatin; D013972:Thyrotropin; D004247:DNA; D013974:Thyroxine