Clinical, Biochemical, Molecular, and Therapeutic Analysis of Maple Syrup Urine Disease in Upper Egypt

Abstract

Maple syrup urine disease (MSUD) is an autosomal recessive inherited metabolic disorder caused by mutations in any of the genes encoding for the branched-chain keto dehydrogenase (BCKDH) components. This study screened MSUD patients throughout the whole Upper Egypt describing their symptoms, clinical and laboratory findings, genetic studies, and their treatment, with a 6-month follow-up for their responses. Screening identified three children with MSUD. Homozygous mutation in R195Q single nucleotide polymorphism (SNP) within the BCKDHA gene was found with the second MSUD patient. Follow-up for 6 months to assess the treatment regimens and progression of cases demonstrated that early treatment regimens including a dietary restriction of branched-chain amino acids with L-Carnitine administration could prevent MSUD-associated intellectual disabilities. It was concluded that R195Q SNP is pathogenic, and it may cause inherited forms of MSUD in some patients. MSUD cases have rarely been reported; so these findings will be highly useful for future cases of MSUD in the Upper Egyptian population.

Keywords

MSUD - L-carnitine - R195Q

Publikationsverlauf

Eingereicht: 07. Mai 2020

Angenommen: 22. Juni 2020

Artikel online veröffentlicht:
10. August 2020

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