Heterogeneous Clinical Characteristics of Allan-Herndon-Dudley Syndrome with SLC16A2 Mutations

• 발행기관: 대한소아신경학회
• 저자명: Ji Yeon Han Seungbok Lee Hyewon Woo Soo Yeon Kim Hunmin Kim Byung Chan Lim Hee Hwang Jieun Choi Ki Joong Kim Jong-Hee Chae
• 간행물 정보: 『Annals of Child Neurology(구 대한소아신경학회지)』Annals of Child Neurology vol.29 no.4, 149~158쪽, 전체 10쪽
• 주제분류: 의약학 > 소아과학
• 파일형태: PDF
• 발행일자: 2021.09.30

영문 초록

Purpose: The purpose of this study was to expand our understanding of phenotypic and genetic variation in Allan-Herndon-Dudley syndrome (AHDS), which is a rare X-linked mental retardation syndrome characterized by hypotonia, generalized spasticity, and moderate-to-severe psychomotor retardation. AHDS is caused by a mutation of solute carrier family 16 member 2 (SLC16A2), which encodes monocarboxylate transporter 8 (MCT8), a transporter of triiodothyronine (T3) into neurons. Methods: We enrolled nine patients with AHDS from unrelated families, except for two patients who were cousins, through a retrospective chart review. Clinical features, brain imaging, electroencephalograms, thyroid hormone profiles, and genetic data were reviewed retrospectively and compared with previously reported cases. Results: We found three novel and five previously reported pathogenic variants in nine patients from eight families. All patients presented with hypotonia, spasticity, severe developmental delay, and elevated serum T3 levels. Cataplexy, which is a previously unreported phenotype, was found in two patients with the same mutation. In our cohort, seizures were uncommon (n=1) but intractable. Conclusion: This study broadens the known phenotypic variations of AHDS, ranging from relatively mild global developmental delay to a severe form of encephalopathy with hypotonia, spasticity, and no acquisition of independent sitting. The syndromic classification or genetic etiology of global developmental delay is extremely heterogeneous; therefore, early clinical suspicion is challenging for clinicians. However, severe mental retardation with hypotonia, spasticity, and elevated serum T3 levels in boys is a highly suspicious clinical clue for the early diagnosis of AHDS.

목차

Introduction

Materials and Methods

Results

Discussion

Conflicts of interest

ORCID

Author contribution

Acknowledgements

References

키워드

Allan-Herndon-Dudley syndrome SLC16A2 protein human Mental retardation X-linked Cataplexy