title: Diagnosis of dihydropyrimidinase deficiency in a Chinese boy with dihydropyrimidinuria.
abstract: Dihydropyrimidinase deficiency is an autosomal recessive inborn error of metabolism characterised by the presence of dihydropyrimidinuria. Its clinical presentation is variable and has also been reported in asymptomatic subjects. We report the first case of dihydropyrimidinase deficiency in Hong Kong, which is also the first reported in a Chinese subject. The patient was a 32-month-old boy who presented with language development delay. Biochemical analysis confirmed markedly increased urinary excretion of dihydrouracil and dihydrothymine, whilst DNA testing confirmed that the patient was compound heterozygous for two missense mutations, one known (p.R302Q) and the other was novel (p.N16K).
authors.affiliation: Division of Clinical Biochemistry, Queen Mary Hospital, Pokfulam, Hong Kong.
authors.forename: C W
authors.initials: CW
authors.lastname: Yeung
authors.forename: M M
authors.initials: MM
authors.lastname: Yau
authors.forename: C K
authors.initials: CK
authors.lastname: Ma
authors.forename: T S
authors.initials: TS
authors.lastname: Siu
authors.forename: Sidney
authors.initials: S
authors.lastname: Tam
authors.forename: C W
authors.initials: CW
authors.lastname: Lam
mesh_terms: D002675:Child, Preschool; D002681:China; D054067:Dihydropyrimidine Dehydrogenase Deficiency / Q000175:diagnosis* / Q000209:etiology; D006723:Hong Kong; D006801:Humans; D008297:Male; D008661:Metabolism, Inborn Errors / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D020125:Mutation, Missense; D014498:Uracil / Q000031:analogs & derivatives / Q000652:urine
chemical_list: C007419:dihydrouracil; D014498:Uracil
keywords: Alanine/urine; Amidohydrolases/deficiency; Liver/metabolism