title: Changes of Thyroid Hormones and Their Binding Proteins during Plasma Exchange for Polyneuropathy in a Patient with Substituted Hypothyroidism due to Hashimoto's Thyroiditis.
abstract: BACKGROUND
  Pharmacodynamic studies and data concerning adaptation of thyroid substitution in patients with substituted hypothyroidism during plasma exchange (PE) is not available.
  
  
  METHODS
  We measured TSH, fT3 and fT4, total T4, thyroxin binding globulin (TBG), and albumin before and after 5 PE procedures in a 37-year-old women who underwent PE for a therapy-resistant polyneuropathy. Thyroxin was increased empirically by 8% resulting in a dose of 1.95 µg/kg per day.
  
  
  RESULTS
  Despite larger reductions of total T4 and TBG over a series of 5 PEs (40-50% from baseline), only small reductions of 8% in fT3 and fT4 concentrations were documented with a concomittant increase in TSH level. Changes of fT4, fT3, and TSH remained within normal range.
  
  
  CONCLUSIONS
  i) Despite a significant decrease in total thyroid hormone pool following PE, fT4, fT3, and TSH concentrations changed only slightly. ii) Based on this observation, a general increase in thyroid replacement therapy before PE cannot be recommended, but considered in case of a high normal TSH level.
authors.affiliation: Department of Endocrinology, Diabetology and Clinical Nutrition, Bern University Hospital, Inselspital, Bern, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Jenni
authors.affiliation: University Clinic of Haematology and Central Haematology Laboratory, Bern University Hospital, Inselspital, Bern, Switzerland.
authors.forename: Marcel
authors.initials: M
authors.lastname: Adler
authors.affiliation: Department of Endocrinology, Diabetology and Clinical Nutrition, Bern University Hospital, Inselspital, Bern, Switzerland.
authors.forename: Simone
authors.initials: S
authors.lastname: Lanz
authors.affiliation: University Clinic of Haematology and Central Haematology Laboratory, Bern University Hospital, Inselspital, Bern, Switzerland.
authors.forename: Behrouz Mansouri
authors.initials: BM
authors.lastname: Taleghani
authors.affiliation: Department of Endocrinology, Diabetology and Clinical Nutrition, Bern University Hospital, Inselspital, Bern, Switzerland.
authors.forename: Emanuel R
authors.initials: ER
authors.lastname: Christ
keywords: Hypothyroidism; Plasma exchange; Substitution; Thyroid hormones