Monitoring of phenylalanine levels in patients with phenylketonuria using dried blood spots : a comparison of two methods

Autor: Fernanda Medeiros Sebastião, Ida Vanessa Doederlein Schwartz, Angela Sitta, Kristiane Michelin Tirelli, Maira Graeff Burin, Moacir Wajner, Fernanda Hendges de Bitencourt, Carmen Regla Vargas, Daniella de Moura Coelho, Gabriel Civallero, Roberto Giugliani
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Repositório Institucional da UFRGS
Universidade Federal do Rio Grande do Sul (UFRGS)
instacron:UFRGS
Journal of Inborn Errors of Metabolism and Screening, Vol 8 (2020)
Journal of Inborn Errors of Metabolism and Screening, Volume: 8, Article number: e20190011, Published: 16 MAR 2020
Journal of Inborn Errors of Metabolism and Screening v.8 2020
Journal of Inborn Errors of Metabolism and Screening
Instituto Genética para Todos (IGPT)
instacron:IGPT
Popis: Phenylketonuria (PKU) is caused by deficient activity of phenylalanine hydroxylase (PAH), responsible for the conversion of phenylalanine (Phe) to tyrosine (Tyr). Monitoring of patients with PKU requires the measurement of Phe in plasma using high-performance liquid chromatography (HPLC) or in dried blood spots (DBS) using different techniques to adjust treatment strategy. The objective of this study was to evaluate Phe levels in DBS measured by two different methods and compare them with Phe levels measured in plasma by HPLC. We analyzed 89 blood samples from 47 PKU patients by two different methods: fluorometric method developed in-house (method A) and the commercially available PerkinElmer® Neonatal Phenylalanine Kit (method B) and in plasma by HPLC. The mean Phe levels by method A, method B, and HPLC were 430.4±39.9μmol/L, 439.3±35.4μmol/L, and 442.2±41.6μmol/L, respectively. The correlation values between HPLC and methods A and B were 0.990 and 0.974, respectively (p < 0.001 for both). Our data suggest that methods A and B are useful alternatives for monitoring Phe levels in patients with PKU, with method A being in closer agreement with the reference standard (HPLC).
Databáze: OpenAIRE