1 Haga clic para modificar el estilo de subtítulo del patrón Comparación de un nuevo reactivo de Anfetaminas (AMPS2) de Roche Diagnostics GmbH en Cobas 6000 y Cobas 8000, para valores de corte de 300 y 500 ng/mL ABSTRACT Amphetamines (amphetamine, methamphetamine, MDMA, MDA and others) are chemical stimulants affecting the central nervous system (CNS) and pharmacologically related to epinephrine and norepinephrine. These substances increase wakefulness, suppress appetite and cause a feeling of increased energy, self-confidence, well-being and euphoria. Abuse can lead to medical, psychological and social consequences. Adverse health effects include memory loss, aggression, psychotic behavior, heart damage, malnutrition, and severe dental problems. The Roche Diagnostics GmbH assay for the detection of amphetamines (AMP, MDMA, MDEA and designer drugs in urine uses the principle of kinetic interaction of microparticles in solution (KIMS), measuring changes in light transmission at a wavelength of 600 nm. The formulation of the assay reagent was recently changed with main objective of increasing the stability. OBJECTIVES The objective of the study is to evaluate the performance of the updated AMPS2 assay on cobas 6000 and cobas 8000 under field conditions. The updated AMPS2 test is compared to the present formulation. Discrepant results were confirmed by gas chromatography / mass spectrometry (GC-MS) by Roche. MATERIAL AND METHODS The updated AMPS2 (Roche Diagnostics GmbH) is evaluated against current reagent, using two platforms, cobas 6000 and cobas 8000 (Roche Diagnostics Ltd.) for two cutoff values (300 ng / mL, and 500 ng / ml) in semi-quantitative mode. Results between different platforms are also compared. 500 selected patient urine samples, from urine screening programs and drug controls for the analysis of drugs of abuse are used. Three types of output for each cutoff value are established: negative (N), positive (P), and gray zone (ZG), while for the cutoff value of 300 (N 330, ZG 270> X 550, ZG 450> X X 550, ZG 450>X 300, neg 500, neg