Analytical performance of Abbott C-16000 analyser haemolysis index and its potential use in measuring plasma cell-free haemoglobin.

Purpose: Measurement of the haemolysis index (HI) is usually performed in clinical chemistry laboratories in order to inform about whether biological analyses are influenced by in vivo or in vitro haemolysis of the specimen. Our aim was to evaluate the analytical performance of Abbott C-16000 analyser HI measurement in order to determine whether this could be used to reliably measure cell-free haemoglobin (fHB) in plasma samples. Methods: The repeatability, reproducibility, lower limit of detection (LLOD) and lower limit of quantification (LLOQ) of C-16000 HI measurement were determined as well as the potential interference of bilirubin, triglycerides and myoglobin. C-16000 HI values of biological samples with various ranges of fHB were compared to those measured using the established reference method, second-derivate spectroscopy. Results: Results: C-16000 HI determination showed excellent linear correlation with the reference method (y = 1.0043x ­ 1.248, R² = 0.998), a broad analytical measurement range (400-20,000 mg/L; y = 0.9904x + 72.972, R² = 0.999), clinically relevant LLOD (56 mg/L) and LLOQ (84 mg/L), good repeatability (coefficient of variation (CV) = 1-15%) and good reproducibility (CV = 5-7%). No interference was observed with myoglobin at concentrations as high as 35,447 mg/L, unconjugated and conjugated bilirubin (at concentrations up to 500 mg/L and 375 mg/L, respectively) or triglycerides up to 6.8 mmol/L. However, a significant underestimation of fHB concentrations was observed at higher triglyceride levels. Conclusion: This study demonstrates that Abbott C-16000 analyser HI is reliable and accurately measures plasma fHB concentrations under pathophysiological conditions except when there are high blood concentrations of triglycerides.

Testing for SGT-151 (CUMYL-PEGACLONE) and its Metabolites in Blood and Urine after Surreptitious Administration.

The authors aim to report a case of surreptitious administration of a synthetic cannabinoid (SC) and the subsequent toxicological investigations to be able to document accurately the case for submission at a hearing. A dealer gave surreptitiously a substance to two juvenile migrants who experienced shakings and faintness. The laboratory received a blood sample from each of the two victims, who, according to the investigators, were probably exposed to SGT-151, a SC, also known as CUMYL-PEGACLONE. Blood and urine specimens from the dealer, who claimed being a user of SGT-151 were received at the same time. To characterize the metabolites of SGT-151, the drug was incubated with a pool of human hepatic microsomes and the cofactors required to ensure the functioning of the main Phase I and Phase II enzymes. The incubation media were analyzed by liquid chromatography coupled to high-resolution mass spectrometry. The metabolites identified following transformation by hepatic microsomes were mostly N-dealkylated SGT-151, mono-hydroxylated SGT-151 and di-hydroxylated SGT-151. The presence of SGT-151 (5.4 ng/mL) and its metabolite, N-dealkyl SGT-151, was confirmed in the dealer's blood. Two metabolites of SGT-151 (OH-SGT-151, diOH-SGT-151) were detected in the dealer's urine. SGT-151 (~1 ng/mL) and its metabolite N-dealkyl SGT-151 were detected in the blood samples of the two victims.