title: Persistent hyperthyrotropinemia in congenital hypothyroidism: successful combination treatment with levothyroxine and liothyronine.
abstract: BACKGROUND
  Some children with congenital hypothyroidism (CH), have persistent hyperthyrotropinemia despite good compliance with levothyroxine.
  
  
  OBJECTIVE
  To evaluate combination therapy of liothyronine (cytomel) with levothyroxine in CH with persistent hyperthyrotropinemia.
  
  
  METHODS
  Files were reviewed retrospectively. Eight female patients with persistently high levels of TSH and upper normal FT4 levels were given either 6.25 or 12 microg liothyronine and the levothyroxine dose was reduced appropriately. Pre- and post-intervention hormone levels and drug doses were evaluated.
  
  
  RESULTS
  TSH decreased in 8/8 and normalized in 6/8 patients. FT4 and free tri-iodothyronine (FT3) remained normal. The levothyroxine-equivalent dose on the combination was 5.0 +/- 0.3 microg/kg/day in infants and 3.4 +/- 0.4 microg/kg/day in children above 2.5 years. Infants required higher liothyronine doses compared with older children (0.66 +/- 0.01 vs. 0.3 +/- 0.05 microg/kg/day).
  
  
  CONCLUSIONS
  Combined therapy can achieve normal TSH levels with normal FT4 and FT3. Further long-term research is required to investigate effects on neurodevelopmental outcome.
authors.affiliation: Pediatric Specialists Clinic, Endocrinology and Diabetes, Clalit Health Services, Jerusalem, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Strich
authors.forename: Larisa
authors.initials: L
authors.lastname: Naugolny
authors.forename: David
authors.initials: D
authors.lastname: Gillis
mesh_terms: D002648:Child; D002675:Child, Preschool; D003409:Congenital Hypothyroidism / Q000097:blood* / Q000188:drug therapy*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010349:Patient Compliance; D012189:Retrospective Studies; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000008:administration & dosage* / Q000097:blood; D014284:Triiodothyronine / Q000008:administration & dosage* / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine