title: A 7-month-old male with Allan-Herndon-Dudley syndrome and the power of T3.
abstract: Allan-Herndon-Dudley syndrome (AHDS, MIM 300523) is an X-linked neurodegenerative disorder characterized by intellectual disability, severe hypotonia, diminished muscle mass, and progressive spastic paraplegia. All affected males have pathognomonic thyroid profiles with an elevated T3 , low-normal free T4 , and normal TSH. Mutations in the monocarboxylate transporter 8 (MCT8) gene, SLC16A2, have been found to be causative. Here, we describe a proband whose extensive evaluation and ultimate diagnosis of AHDS unmasked three previously undiagnosed generations of affected individuals in one family. This case illustrates the need for clinicians to consider obtaining full thyroid studies on individuals with the non-specific findings of severe hypotonia, failure to thrive, and gross motor delay.
authors.affiliation: Department of Pediatrics, Eastern Virginia Medical School, Norfolk, Virginia; Division of Medical Genetics and Metabolism, Children's Hospital of The King's Daughters, Norfolk, Virginia.
authors.forename: Katherine G
authors.initials: KG
authors.lastname: Langley
authors.forename: Steven
authors.initials: S
authors.lastname: Trau
authors.forename: Lora J H
authors.initials: LJ
authors.lastname: Bean
authors.forename: Alekhya
authors.initials: A
authors.lastname: Narravula
authors.forename: Samantha A
authors.initials: SA
authors.lastname: Schrier Vergano
mesh_terms: D000015:Abnormalities, Multiple; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000097:blood / Q000235:genetics / Q000503:physiopathology; D008297:Male; D038901:X-Linked Intellectual Disability / Q000097:blood / Q000235:genetics* / Q000503:physiopathology; D009123:Muscle Hypotonia / Q000097:blood / Q000235:genetics* / Q000503:physiopathology; D009133:Muscular Atrophy / Q000097:blood / Q000235:genetics* / Q000503:physiopathology; D009154:Mutation; D010264:Paraplegia / Q000097:blood / Q000235:genetics* / Q000503:physiopathology; D010375:Pedigree; D014284:Triiodothyronine / Q000097:blood* / Q000235:genetics
chemical_list: D014284:Triiodothyronine
keywords: Allan-Herndon-Dudley; T3; X-linked; hypotonia; spastic paraplegia