Novel mutation in MCT8 gene in a Brazilian boy with thyroid hormone resistance and severe neurologic abnormalities.
Arq Bras Endocrinol Metabol
; 55(1): 60-6, 2011 Feb.
Article
en En
| MEDLINE
| ID: mdl-21468521
ABSTRACT
MCT8 is a cellular transporter of thyroid hormones important in their action and metabolization. We report a male patient with the novel inactivating mutation 630insG in the coding region in exon 1 of MCT8. He was characterized clinically by severe neurologic impairment (initially with global hypotonia, later evolving with generalized hypertonia), normal growth during infancy, reduced weight gain, and absence of typical signs and symptoms of hypothyroidism, while the laboratory evaluation disclosed elevated T3, low total and free T4, and mildly elevated TSH serum levels. Treatment with levothyroxine improved thyroid hormone profile but was not able to alter the clinical picture of the patient. These data reinforce the concept that the role of MCT8 is tissue-dependent while neurons are highly dependent on MCT8, bone tissue, adipose tissue, muscle, and liver are less dependent on MCT8 and, therefore, may suffer the consequences of the exposition to high serum T3 levels.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Triyodotironina
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Encefalopatías
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Síndrome de Resistencia a Hormonas Tiroideas
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Transportadores de Ácidos Monocarboxílicos
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Mutación
Límite:
Child
/
Humans
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Male
País/Región como asunto:
America do sul
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Brasil
Idioma:
En
Año:
2011
Tipo del documento:
Article