title: Early discontinuation of thyroxine therapy is possible in most very low-birthweight infants with hypothyroidism detected by screening.
abstract: OBJECTIVE
  To determine the feasibility of discontinuing thyroid hormone treatment earlier than recommended by the current guidelines for congenital hypothyroidism.
  
  
  METHODS
  We retrospectively reviewed the medical records of very low-birthweight (VLBW) infants born at Chungbuk National University Hospital from January 2006 to December 2010. Infants were divided into two groups--hypothyroid and normal thyroid--on the basis of the thyroid function test results. Infants in the hypothyroid group were treated with levothyroxine (L-T4) and attempts to discontinue this therapy began when they were about 2 years old.
  
  
  RESULTS
  Of the 216 infants born during the study period, 20 died and 196 were included in the study. Of these, 46 were in the hypothyroid group and 150 were in the normal thyroid group. Thirty-nine infants were taken off L-T4 therapy at around 2 years of age. All were successfully weaned off L-T4 and retained normal thyroid function. Tc-99 m thyroid scans were performed in 32 infants, and no distinct abnormality was noted.
  
  
  CONCLUSIONS
  Thyroid dysfunction in VLBW infants was common in our cohort and most cases were transient. Attempts to discontinue this therapy could begin at around the age of two or earlier when low doses of L-T4 have achieved maintenance.
authors.affiliation: Department of Pediatrics, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.
authors.forename: Gina
authors.initials: G
authors.lastname: Lim
authors.forename: Youn Kyung
authors.initials: YK
authors.lastname: Lee
authors.forename: Heon-Seok
authors.initials: HS
authors.lastname: Han
mesh_terms: D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology; D015994:Incidence; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D062606:Tertiary Care Centers; D013974:Thyroxine / Q000008:administration & dosage*
chemical_list: D013974:Thyroxine
keywords: Congenital hypothyroidism; Thyroxine; Transient hypothyroidism; Very low-birthweight infant