Familial Dysalbuminemic Hyperthyroxinemia that was Inappropriately Treated with Thiamazole Due to Pseudo-thyrotoxic Symptoms

Intern Med. 2017 Aug 15;56(16):2175-2180. doi: 10.2169/internalmedicine.8619-16. Epub 2017 Aug 1.

Abstract

We herein report the case of a Japanese woman with familial dysalbuminemic hyperthyroxinemia (FDH) who was initially diagnosed with Graves' disease. Direct genomic sequencing revealed a guanine to cytosine transition in the second nucleotide of codon 218 in exon 7 of the albumin gene, which then caused a proline to arginine substitution. She was finally diagnosed with FDH, which did not require treatment. FDH is - superficially - an uncommon cause of syndrome of inappropriate secretion of thyrotropin (SITSH) in Japan. A misdiagnosis of pseudo-hyperthyroidism will lead to inappropriate treatment. Thus, physicians should strongly note the possibility of FDH as a differential diagnosis of SITSH.

Keywords: SITSH; familial dysalbuminemic hyperthyroxinemia (FDH); thiamazole.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Antithyroid Agents / therapeutic use*
  • Codon
  • Diagnosis, Differential
  • Female
  • Graves Disease / diagnosis
  • Humans
  • Hyperpituitarism / etiology
  • Hyperthyroxinemia, Familial Dysalbuminemic / complications
  • Hyperthyroxinemia, Familial Dysalbuminemic / diagnosis*
  • Hyperthyroxinemia, Familial Dysalbuminemic / drug therapy*
  • Hyperthyroxinemia, Familial Dysalbuminemic / genetics
  • Methimazole / therapeutic use*
  • Mutation
  • Serum Albumin / genetics
  • Thyroid Gland / diagnostic imaging
  • Thyrotropin / metabolism
  • Ultrasonography

Substances

  • Antithyroid Agents
  • Codon
  • Serum Albumin
  • Methimazole
  • Thyrotropin