Urine Phenylacetylglutamine Determination in Patients with Hyperphenylalaninemia.
Fernando AndradeAinara CanoMaría Unceta SuarezArantza ArzaAna VinuesaLeticia CeberioNuria López-OsléGorka de FrutosRaquel López-OcejaElena AznalDomingo González-LamuñoJavier de Las Heras MonteroPublished in: Journal of clinical medicine (2021)
Phenylketonuria (PKU), an autosomal-recessive inborn error of phenylalanine (Phe) metabolism is the most prevalent disorder of amino acid metabolism. Currently, clinical follow-up relies on frequent monitoring of Phe levels in blood. We hypothesize that the urine level of phenylacetylglutamine (PAG), a phenyl-group marker, could be used as a non-invasive biomarker. In this cross-sectional study, a validated liquid chromatography coupled to tandem mass spectrometry (LC-MS) method was used for urinary PAG quantification in 35 participants with hyperphenylalaninemia (HPA) and 33 age- and sex-matched healthy controls. We have found that (a) PKU patients present higher urine PAG levels than healthy control subjects, and that (b) there is a significant correlation between urine PAG and circulating Phe levels in patients with HPA. In addition, we show a significant strong correlation between Phe levels from venous blood samples and from capillary finger-prick dried blood spot (DBS) samples collected at the same time in patients with HPA. Further research in order to assess the potential role of urine PAG as a non-invasive biomarker in PKU is warranted.
Keyphrases
- tandem mass spectrometry
- liquid chromatography
- ultra high performance liquid chromatography
- solid phase extraction
- simultaneous determination
- high performance liquid chromatography
- end stage renal disease
- mass spectrometry
- amino acid
- newly diagnosed
- chronic kidney disease
- gas chromatography
- high resolution
- intellectual disability
- patient reported outcomes
- molecularly imprinted
- muscular dystrophy