TY - JOUR
T1 - Thyroid morphology and function in adults with untreated isolated growth hormone deficiency
AU - Alcântara, Marta Regina Silva
AU - Salvatori, Roberto
AU - Alcântara, Paula Regina Silva
AU - Nóbrega, Luciana Michele A.
AU - Campos, Vera Simone
AU - Oliveira, Elma Cristina O.
AU - Oliveira, Marcelo Henrique S.
AU - Souza, Anita Hermínia Oliveira
AU - Aguiar-Oliveira, Manuel Hermínio
PY - 2006/3
Y1 - 2006/3
N2 - Objective: GH influences thyroid function and anatomy. Although goiter is frequent in acromegalic patients, the effects of GH deficiency (GHD) are difficult to assess, because hypopituitaric subjects who lack GH often also have a partial or complete deficit of TSH. Study Design: We studied thyroid morphology and serum levels of thyroid hormones in adult members of a large Brazilian kindred with untreated isolated GHD due to a homozygous mutation in the GHRH receptor gene (GHRHR; nine men and 15 women; GHD group) and compared them to subjects heterozygous for the same mutation (eight men and 10 women; HET group) and subjects homozygous for the wild-type allele [seven men and 11 women; control (CO) group]. Results: GHD subjects had a smaller thyroid volume (TV) than HET and CO. The TV of the HET group was intermediate between those of the GHD and CO groups. When TV was corrected by body surface area, it remained smaller in the GHD and HET groups than in the CO group, but the difference betweenGHDand HET groups disappeared. The GHD group had lower serum T 3 levels than the CO group and higher free T4 levels than HET and CO groups. Conclusions: Individuals with severe untreated GHD due to a homozygous GHRHR mutation and heterozygous carriers of the same mutation have smaller TV than normal subjects, suggesting that GH has a permissive role in the growth of the thyroid gland. In addition, GHD subjects have reduced serum total T3 and increased serum free T4, suggesting a reduction in the function of the deiodinase system.
AB - Objective: GH influences thyroid function and anatomy. Although goiter is frequent in acromegalic patients, the effects of GH deficiency (GHD) are difficult to assess, because hypopituitaric subjects who lack GH often also have a partial or complete deficit of TSH. Study Design: We studied thyroid morphology and serum levels of thyroid hormones in adult members of a large Brazilian kindred with untreated isolated GHD due to a homozygous mutation in the GHRH receptor gene (GHRHR; nine men and 15 women; GHD group) and compared them to subjects heterozygous for the same mutation (eight men and 10 women; HET group) and subjects homozygous for the wild-type allele [seven men and 11 women; control (CO) group]. Results: GHD subjects had a smaller thyroid volume (TV) than HET and CO. The TV of the HET group was intermediate between those of the GHD and CO groups. When TV was corrected by body surface area, it remained smaller in the GHD and HET groups than in the CO group, but the difference betweenGHDand HET groups disappeared. The GHD group had lower serum T 3 levels than the CO group and higher free T4 levels than HET and CO groups. Conclusions: Individuals with severe untreated GHD due to a homozygous GHRHR mutation and heterozygous carriers of the same mutation have smaller TV than normal subjects, suggesting that GH has a permissive role in the growth of the thyroid gland. In addition, GHD subjects have reduced serum total T3 and increased serum free T4, suggesting a reduction in the function of the deiodinase system.
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U2 - 10.1210/jc.2005-2555
DO - 10.1210/jc.2005-2555
M3 - Article
C2 - 16394080
AN - SCOPUS:33644829498
SN - 0021-972X
VL - 91
SP - 860
EP - 864
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 3
ER -