RESUMO
Allan-Herndon-Dudley syndrome (AHDS) is an X-linked intellectual disability caused by monocarboxylate transporter 8 (MCT8) deficiency. AHDS manifests in global developmental delay, axial hypotonia, quadriplegia, movement disorders in male patients, and most of them show the delayed or hypomyelination on brain magnetic resonance images. Typically, Triiodothyronine (T3) levels are markedly elevated, thyroid stimulating hormone (TSH) levels are normal or elevated, and free thyroxine (T4) levels are normal or decreased. In AHDS patients, early neurological manifestations are easily mistaken as cerebral palsy with unknown origin. Here, we present a novel c.826G>A mutation in a boy with severe axial hypotonia, limb dystonia and developmental delay. Thyroid function test including TSH, T3, and free T4 levels was the important clue for the diagnosis of AHDS of the patient.
Assuntos
Humanos , Masculino , Encéfalo , Paralisia Cerebral , Diagnóstico , Distonia , Deficiência Intelectual , Transtornos dos Movimentos , Hipotonia Muscular , Manifestações Neurológicas , Quadriplegia , Testes de Função Tireóidea , Glândula Tireoide , Tireotropina , Tiroxina , Tri-IodotironinaRESUMO
Thyroid hormones play important roles in growth, development, and metabolism of various cells and tissues. It has been assumed for a long time that thyroid hormones are lipophilic and enter cells by passive diffusion, but it has become increasingly clear that cellular uptake and efflux of thyroid hormones are mediated by transporters. The discovery of these thyroid hormone transporters will lead to a better understanding of the tissuespecific regulation of thyroid hormones.