title: Diagnostic and predictive value of ultrasound and isotope thyroid scanning, alone and in combination, in infants referred with thyroid-stimulating hormone elevation on newborn screening.
abstract: OBJECTIVE
  To determine the diagnostic and predictive value of ultrasound and radioisotope scans of the thyroid, alone and in combination, during a single visit after initial referral by the screening laboratory with thyroid-stimulating hormone (TSH) elevation.
  
  
  METHODS
  Retrospective blind review of ultrasound and radioisotope images followed by final diagnosis based on clinical features, biochemistry, imaging, and molecular genetic study.
  
  
  RESULTS
  Infants (n = 97; 61 female) with median birthweight 3.38 kg (range 2.04-4.86) and gestation 40 weeks (range 33-42), underwent successful dual thyroid ultrasound and technetium-99m pertechnetate radioisotope scan in a single center. Combined scanning at the initial visit resulted in a correct final diagnosis in 79 of 97 (81%) cases. One patient was misdiagnosed initially as having athyreosis as the result of delayed radioisotope scan and the diagnosis of ectopia made later on diagnostic challenge. The specificity/sensitivity for radioisotope scan and for ultrasound was as follows: 100%/97% and 100%/55% for ectopia (n = 39); 81%/100% and 54%/100% for athyreosis (n = 18); and 89%/90% and 80%/95% for dyshormonogenesis (n = 20). Neither modality, alone or in combination, predicted final diagnosis in eutopic glands due to hypoplasia (n = 4), transient TSH elevation (n = 12), and status still uncertain (n = 4).
  
  
  CONCLUSIONS
  More than 80% of newborn infants with TSH elevation can be diagnosed correctly on initial imaging with combined radioisotope scan and ultrasound. Ultrasound cannot reliably detect thyroid ectopia. Radioisotope scan, especially if performed late, may show no uptake despite the presence of a eutopic gland.
authors.affiliation: Child Health Unit, Royal Hospital for Sick Children, Yorkhill, Glasgow, United Kingdom.
authors.forename: Angela
authors.initials: A
authors.lastname: Lucas-Herald
authors.affiliation: Child Health Unit, Royal Hospital for Sick Children, Yorkhill, Glasgow, United Kingdom.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Jones
authors.affiliation: Department of Radiology, Royal Hospital for Sick Children, Yorkhill, Glasgow, United Kingdom.
authors.forename: Morag
authors.initials: M
authors.lastname: Attaie
authors.affiliation: Department of Radiology, British Columbia Children's Hospital, Vancouver, Canada.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Maroo
authors.affiliation: Department of Pediatrics, University Hospital, Hradec Králové, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Neumann
authors.affiliation: West of Scotland Medical Genetic Service, Southern General Hospital, Glasgow, United Kingdom.
authors.forename: Therese
authors.initials: T
authors.lastname: Bradley
authors.affiliation: Children's Hospital, University of Mainz, Mainz, Germany.
authors.forename: Pia
authors.initials: P
authors.lastname: Hermanns
authors.affiliation: Children's Hospital, University of Mainz, Mainz, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Pohlenz
authors.affiliation: Child Health Unit, Royal Hospital for Sick Children, Yorkhill, Glasgow, United Kingdom. Electronic address: malcolm.donaldson@glasgow.ac.uk.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Donaldson
mesh_terms: D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000000981:diagnostic imaging*; D007231:Infant, Newborn; D008297:Male; D064847:Multimodal Imaging; D015997:Neonatal Screening / Q000379:methods*; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012017:Referral and Consultation; D012189:Retrospective Studies; D013670:Sodium Pertechnetate Tc 99m; D013972:Thyrotropin / Q000097:blood*; D014463:Ultrasonography
chemical_list: D019275:Radiopharmaceuticals; D013972:Thyrotropin; D013670:Sodium Pertechnetate Tc 99m