Publication: Simultaneous determination of 5-hydroxytryptophan and 3-O-methyldopa in dried blood spot by UPLC-MS/MS: A useful tool for the diagnosis of L-amino acid decarboxylase deficiency

This original study article, published in the Journal of Chromatography B, outlines a study to establish a reliable method to assess both 5-hydroxytryptophan (5-HTP) and 3-O-methyldopa (3-OMD) in dried blood spot (DBS) analysis through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) technology, for the biochemical diagnosis of AADC deficiency

  • Review the role of high-performance liquid chromatography (HPLC) analysis of cerebrospinal fluid (CSF) neurotransmitter metabolites in the diagnosis of AADC deficiency
  • Find out about a new tool for the detection of 5-HTP alongside 3-OMD in DBS for the diagnosis of AADC deficiency
  • Understand the mechanism behind simultaneous measurement of 5-HTP and 3-OMD in DBS and how this improves the specificity and sensitivity of the biochemical diagnosis of AADC deficiency is discussed

Di Carlo E, et al. J Chromatogr B Analyt Technol Biomed Life Sci. 2021;1185:122999

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▼ Eladocagene exuparvovec is subject to additional monitoring. This will allow quick identification of new safety information. Healthcare professionals are asked to report any suspected adverse reactions via the national reporting system. Adverse events should also be reported to PTC Therapeutics at

Eladocagene exuparvovec (UpstazaTM) is a gene therapy indicated for the treatment of patients aged 18 months and older with a clinical, molecular, and genetically confirmed diagnosis of AADC deficiency with a severe phenotype, currently licensed in the European Member States, Great Britain, Iceland, Liechtenstein, Northern Ireland and Norway.

Registration conditions differ internationally; always consult local prescribing information and/or Summary of Product Characteristics before prescribing any product.

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MED-ALL-AADC-2200023 | October 2023
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