Late-onset mucopolysaccharidosis type IIIA mimicking Usher syndrome.
Am J Med Genet A
; 194(5): e63517, 2024 May.
Article
em En
| MEDLINE
| ID: mdl-38149346
ABSTRACT
Mucopolysaccharidosis type IIIA (MPS IIIA or Sanfilippo syndrome type A) is an autosomal recessive lysosomal storage disorder caused by pathogenic variants in the SGSH gene encoding N-sulfoglucosamine sulfohydrolase, an enzyme involved in the degradation of heparan sulfate. MPS IIIA is typically characterized by neurocognitive decline and hepatosplenomegaly with childhood onset. Here, we report on a 53-year-old male subject initially diagnosed with Usher syndrome for the concurrence of retinitis pigmentosa and sensorineural hearing loss. Clinical exome sequencing identified biallelic missense variants in SGSH, and biochemical assays showed complete deficiency of sulfamidase activity and increased urinary glycosaminoglycan excretion. Reverse phenotyping revealed left ventricle pseudo-hypertrophy, hepatosplenomegaly, bilateral deep white matter hyperintensities upon brain MRI, and decreased cortical metabolic activity by PET-CT. On neuropsychological testing, the proband presented only partial and isolated verbal memory deficits. This case illustrates the power of unbiased, comprehensive genetic testing for the diagnosis of challenging mild or atypical forms of MPS IIIA.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Mucopolissacaridose III
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Síndromes de Usher
Limite:
Child
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Am J Med Genet A
Assunto da revista:
GENETICA MEDICA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Itália