Simultaneous determination of urinary catecholamines and free metanephrines by UHPLC-MSMS for diagnosis of pheochromocytomas and paragangliomas

MARIA EUGENIA RODRÍGUEZ; AMBAO VERÓNICA; MARÍA GABRIELA BALLERINI; ANA VIEYTES; GABRIELA SANSÓ; IGNACIO BERGADÁ; MARÍA GABRIELA ROPELATO

Congreso; 11th International Meeting of Paediatric Endocrinology (IMPE); 2023

Background: Catecholamines and its O-methylated metabolites in urine are useful biomarkers for diagnosis of Pheochromocytoma and Paraganglioma (PPGL). Recently, liquid chromatography coupled to tandem mass spectrometry (UHPLCMSMS) has become the technique that allows the development of analytical methodologies for the specific, precise, and simultaneous determination of different analytes.Objective: To develop and validate an UHPLC-MS/MS method for the simultaneous quantification of Epinephrine (EPI), norepinephrine (NE), dopamine (DA), metanephrine (MN), normetanephrine (NMN) and 3-methoxytyramine (3MT) for diagnosis of (PPGL).Methods: UHPLC-MS/MS system (Shimadzu Nexera 20A-AB Sciex QTRAP®6500 system). Method performance was validated for recovery, linearity, precision, accuracy, ion suppression and carry over. Lower limit of detection (LLD: signal/noise ratio 3), lower limit of quantitation (LLOQ: the lowest concentration with CV% 0.99. LLQ were EPI 4.09, NE: 8.87, DA: 130.57, MN: 5.68, NMN: 40.4, 3MT: 40 nmol/24hs n PPGL patients, NE was elevated in 14 and NMN in 17/19 samples. Of note, 3MT was elevated in all patients with MD and 10 patients with PPGL. Samples results (nmol/24hs) are shown in the table (mean ± SEM, a P