TY - JOUR
T1 - Retinal photoreceptor functions are compromised in patients with resistance to thyroid hormone syndrome (RTHb)
AU - Campi, Irene
AU - Cammarata, Gabriella
AU - Marzoli, Stefania Bianchi
AU - Beck-Peccoz, Paolo
AU - Santarsiero, Diletta
AU - Dazzi, Davide
AU - De Castello, Alessandra Bottari
AU - Taroni, Elena Giuliana
AU - Viola, Francesco
AU - Mian, Caterina
AU - Watutantrige-Fernando, Sara
AU - Pelusi, Carla
AU - Muzza, Marina
AU - Maffini, Maria Antonia
AU - Persani, Luca
PY - 2017/7/1
Y1 - 2017/7/1
N2 - Context: In animalmodels, disruption of thyroid hormone (TH) receptor-b (TRb) 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 (RTHb) with dominant-negative TRb mutations. Objective: To investigate RP functions in RTHb. Design, Setting, and Participants: Case-control study involving 27 RTHb patients and 31 age/sexmatched controls, conducted in two tertiary referral centers in Italy. Main Outcome Measures: 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. Results: Color sensitivity was worse in RTHb patients than controls (P = 0.002). CMT was overlapping between the study groups but directly correlated with sex hormone-binding globuline levels in RTHb.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 RTHb patients compared with controls. The response of the L/M cones measured by a specialized ERG test was lower in RTHb 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. Conclusions: We report, to our knowledge, the first in vivo evidence of functional defects of RP in RTHb. These changes occur independently of endogenous TH levels or the prenatal exposure to high or normal maternal TH.
AB - Context: In animalmodels, disruption of thyroid hormone (TH) receptor-b (TRb) 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 (RTHb) with dominant-negative TRb mutations. Objective: To investigate RP functions in RTHb. Design, Setting, and Participants: Case-control study involving 27 RTHb patients and 31 age/sexmatched controls, conducted in two tertiary referral centers in Italy. Main Outcome Measures: 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. Results: Color sensitivity was worse in RTHb patients than controls (P = 0.002). CMT was overlapping between the study groups but directly correlated with sex hormone-binding globuline levels in RTHb.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 RTHb patients compared with controls. The response of the L/M cones measured by a specialized ERG test was lower in RTHb 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. Conclusions: We report, to our knowledge, the first in vivo evidence of functional defects of RP in RTHb. These changes occur independently of endogenous TH levels or the prenatal exposure to high or normal maternal TH.
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U2 - 10.1210/jc.2016-3671
DO - 10.1210/jc.2016-3671
M3 - Article
AN - SCOPUS:85023193236
VL - 102
SP - 2620
EP - 2627
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 7
ER -