title: Retinal Photoreceptor Functions Are Compromised in Patients With Resistance to Thyroid Hormone Syndrome (RTHβ).
abstract: In animal models, disruption of thyroid hormone (TH) receptor-β (TRβ) reduces the long/medium wavelength (L/M) and increases the short-wavelength (S) cones. Retinal photoreceptor (RP) functions are unknown in patients with resistance to TH syndrome (RTHβ) with dominant-negative TRβ mutations.
  
  
  
  To investigate RP functions in RTHβ.
  
  
  
  Case-control study involving 27 RTHβ patients and 31 age/sex-matched controls, conducted in two tertiary referral centers in Italy.
  
  
  
  Color vision sensitivity assessed by Farnsworth; central macular thickness (CMT) of the outer retinal layer measured by spectral-domain optical coherence tomography; and retinal function tested by full-field electroretinogram (ERG) and S-cone ERG.
  
  
  
  Color sensitivity was worse in RTHβ patients than controls (P = 0.002). CMT was overlapping between the study groups but directly correlated with sex hormone-binding globuline levels in RTHβ. We found a significant reduction in amplitude of the cone (P = 0.024) and of the rod response (P = 0.006) in the ERG of RTHβ patients compared with controls. The response of the L/M cones measured by a specialized ERG test was lower in RTHβ than controls (P = 0.027), whereas no differences were found in the S-cone response. No correlations were found between TH levels, total error score, or electrophysiological results. Furthermore, no differences were found between patients with maternal or de novo/paternal inheritance.
  
  
  
  We report, to our knowledge, the first in vivo evidence of functional defects of RP in RTHβ. These changes occur independently of endogenous TH levels or the prenatal exposure to high or normal maternal TH.
authors.affiliation: Division of Endocrine and Metabolic Diseases, Laboratory of Endocrine and Metabolic Research, Istituto Di Ricovero e Cura a Carattere Scientifico, Istituto Auxologico Italiano, 20149 Milan, Italy.|Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Campi
authors.affiliation: Neuro-Ophthalmology Service, Electrophysiology Laboratory, Department of Ophthalmology, Istituto Di Ricovero e Cura a Carattere Scientifico, Istituto Auxologico Italiano, 20149 Milan, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Cammarata
authors.affiliation: Neuro-Ophthalmology Service, Electrophysiology Laboratory, Department of Ophthalmology, Istituto Di Ricovero e Cura a Carattere Scientifico, Istituto Auxologico Italiano, 20149 Milan, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Bianchi Marzoli
authors.affiliation: Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Beck-Peccoz
authors.affiliation: Neuro-Ophthalmology Service, Electrophysiology Laboratory, Department of Ophthalmology, Istituto Di Ricovero e Cura a Carattere Scientifico, Istituto Auxologico Italiano, 20149 Milan, Italy.
authors.forename: Diletta
authors.initials: D
authors.lastname: Santarsiero
authors.affiliation: Division of Internal Medicine, Ospedale Vaio, 43036 Fidenza, Parma, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Dazzi
authors.affiliation: Ophthalmology Unit, Fondazione Istituto Di Ricovero e Cura a Carattere Scientifico Ca' Granda, 20122 Milan, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Bottari de Castello
authors.affiliation: Ophthalmology Unit, Fondazione Istituto Di Ricovero e Cura a Carattere Scientifico Ca' Granda, 20122 Milan, Italy.
authors.forename: Elena Giuliana
authors.initials: EG
authors.lastname: Taroni
authors.affiliation: Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy.|Ophthalmology Unit, Fondazione Istituto Di Ricovero e Cura a Carattere Scientifico Ca' Granda, 20122 Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Viola
authors.affiliation: Department of Medicine, Endocrinology Unit-University of Padua, 35128 Padova, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Mian
authors.affiliation: Department of Medicine, Endocrinology Unit-University of Padua, 35128 Padova, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Watutantrige-Fernando
authors.affiliation: Department of Medical and Surgical Sciences, Division of Endocrinology, University of Bologna, Sant'Orsola-Malpighi Hospital, 40138 Bologna, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Pelusi
authors.affiliation: Endocrine Unit, Fondazione Istituto Di Ricovero e Cura a Carattere Scientifico Ca' Granda, 20122 Milan, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Muzza
authors.affiliation: Endocrine Unit, Fondazione Istituto Di Ricovero e Cura a Carattere Scientifico Ca' Granda, 20122 Milan, Italy.
authors.forename: Maria Antonia
authors.initials: MA
authors.lastname: Maffini
authors.affiliation: Division of Endocrine and Metabolic Diseases, Laboratory of Endocrine and Metabolic Research, Istituto Di Ricovero e Cura a Carattere Scientifico, Istituto Auxologico Italiano, 20149 Milan, Italy.|Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Persani
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D055253:Color Vision / Q000502:physiology; D003117:Color Vision Defects / Q000175:diagnosis*; D004594:Electrophysiology; D004596:Electroretinography / Q000379:methods; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology*; D012016:Reference Values; D018709:Statistics, Nonparametric; D062606:Tertiary Care Centers; D013960:Thyroid Function Tests; D018382:Thyroid Hormone Resistance Syndrome / Q000503:physiopathology*; D041623:Tomography, Optical Coherence / Q000379:methods; D055815:Young Adult