Quantification of phosphatidylethanol 16:0/18:1, 18:1/18:1, and 16:0/16:0 in venous blood and venous and capillary dried blood spots from patients in alcohol withdrawal and control volunteers

Phosphatidylethanol species (PEths) are promising biomarkers of alcohol consumption. Here, we report on the set-up, validation, and application of a novel UHPLC-ESI-MS/MS method for the quantification of PEth 16:0/18:1, PEth 18:1/18:1, and PEth 16:0/16:0 in whole blood (30 mu L) and in venous (V, 30 mu L) or capillary (C, 3 punches (3 mm)) dried blood spots (DBS). The methods were linear from 10 (LLOQ) to 2000 ng/mL for PEth 16:0/18:1, from 10 (LLOQ) to 1940 ng/mL for PEth 18:1/18:1, and from 19 (LLOQ) to 3872 ng/mL for PEth 16:0/16:0. Extraction efficiencies were higher than 55 % (RSD < 18 %) and matrix effects compensated for by IS were between 77 and 125 % (RSD < 10 %). Accuracy, repeatability, and intermediate precision fulfilled acceptance criteria (bias and RSD below 13 %). Validity of the procedure for determination of PEth 16:0/18:1 in blood was demonstrated by the successful participation in a proficiency test. The quantification of PEths in C-DBS was not significantly influenced by the hematocrit, punch localization, or spot volume. The stability of PEths in V-DBS stored at room temperature was demonstrated up to 6 months. The method was applied to authentic samples (whole blood, V-DBS, and C-DBS) from 50 inpatients in alcohol withdrawal and 50 control volunteers. Applying a cut-off value to detect inpatients at 221 ng/mL for PEth 16:0/18:1 provided no false positive results and a good sensitivity (86 %). Comparison of quantitative results (Bland-Altman plot, Passing-Bablok regression, and Wilcoxon signed rank test) revealed that V-DBS and C-DBS were valid alternatives to venous blood for the detection of alcohol consumption

Medical emergencies related to ethanol and illicit drugs at an annual, nocturnal, indoor, electronic dance music event

Introduction: Medical problems are frequently encountered during electronic dance music (EDM) events. Problem: There are uncertainties about the frequencies and severity of intoxications with different types of recreational drugs: ethanol, "classical" illicit party drugs, and new psychoactive substances (NPS). Methods: Statistical data on the medical problems encountered during two editions of an indoor electronic dance event with around 30,000 attendants were retrieved from the Belgian Red Cross (Mechelen, Belgium) database. Data on drug use were prospectively collected from the patient (or a bystander), the clinical presentation, and/or toxicological screening. Results: In the on-site medical station, 487 patients were treated (265 in 2013 and 222 in 2014). The most frequent reasons were trauma (n = 171), headache (n = 36), gastro-intestinal problems (n = 44), and intoxication (n = 160). Sixty-nine patients were transferred to a hospital, including 53 with severe drug-related symptoms. Analysis of blood samples from 106 intoxicated patients detected ethanol in 91.5%, 3,4-methylenedioxymethamphetamine (MDMA) in 34.0%, cannabis in 30.2%, cocaine in 7.5%, amphetamine in 2.8%, and gamma-hydroxybutyric acid (GHB) in 0.9% of patients (alone or in combination). In only six of the MDMA-positive cases, MDMA was the sole substance found. In 2014, the neuroleptic drug clozapine was found in three cases and ketamine in one. Additional analyses for NPS were performed in 20 cases. Only in one agitated patient, the psychedelic phenethylamines 25B-NBOMe and 25C-NBOMe were found. Conclusions: At this particular event, recreational drug abuse necessitated on-site medical treatment in one out of 350 attendants and a hospital transfer in one out of 1,000. Ethanol remains the most frequently abused (legal) drug, yet classical illicit recreational drugs are also frequently (co-) ingested. The most worrying observation was high-risk poly-drug use, especially among MDMA users. Regarding NPS, the number of cases was low and the clinical presentations were rather mild. It should be stressed that these observations only apply to this particular event and cannot be generalized to other EDM events

Screening and confirmation methods for GHB determination in biological fluids

The aim of this review is to provide a comprehensive overview of screening and confirmation methods reported to determine the low-molecular weight compound and drug of abuse gamma-hydroxybutyric acid (GHB) in biological fluids. The polar nature, the endogenous presence, rapid metabolization following ingestion and stability issues during storage (de novo formation and interconversion between GHB and its lactone form gamma-butyrolactone), impose challenges for the analyst and for the interpretation of a positive result. First, possible screening procedures for GHB are discussed, including colorimetric, enzymatic and chromatography-based procedures. Confirmation methods for clinical and forensic cases mostly involve gas chromatography (coupled to mass spectrometry), although also liquid chromatography and capillary zone electrophoresis have been applied. Prior to injection, sample preparation techniques include (a combination of) liquid-liquid, solid-phase or headspace extraction, as well as chemical modification of the polar compound. Also simple dilute-and-shoot may be sufficient in the case of urine or serum samples. Advantages, limitations and trends are discussed

Determination of antidepressants in human postmortem blood, brain tissue, and hair using gas chromatography–mass spectrometry

A gas chromatographic-mass spectrometric (GC-MS) method in positive ion chemical ionization mode in combination with a solid phase extraction was optimized for new-generation antidepressants and their metabolites in postmortem blood, brain tissue, and hair. Twelve antidepressants and their active metabolites (i.e., mirtazapine, viloxazine, venlafaxine, citalopram, mianserin, reboxetine, fluoxetine, fluvoxamine, sertraline, maprotiline, melitracen, paroxetine, desmethylfluoxetine, desmethylmianserin, desmethylmirtazapine, desmethylsertraline, desmethylmaprotiline, desmethylcitalopram, and didesmethylcitalopram) could be quantified. In this article, in addition to the validation of the GC-MS method, four postmortem cases are discussed to demonstrate the usefulness of the described method in forensic toxicology. In these cases, sertraline, fluoxetine, citalopram, and trazodone in combination with their active metabolites were quantified. Blood concentrations ranged from subtherapeutic to toxic concentrations, while brain to plasma ratios ranged from 0.8 to 17. Hair concentrations ranged from 0.4 to 2.5 ng/mg depending on the compound and hair segment