Liquid chromatography/time-of-flight mass spectrometry analysis of postmortem blood samples for targeted toxicological screening

Fatal Intoxications with Zopiclone-A Cause for Concern?

INTRODUCTION

Zopiclone, a controlled substance prescribed for insomnia, has become a common toxicological finding in forensic autopsy cases. This study investigated the role and extent of zopiclone use in fatal intoxications in Sweden.

METHODS

All forensic autopsy cases positive for zopiclone in femoral blood during 2012-2020 were selected. Among these cases, fatalities caused by intoxication according to the cause of death certificates issued by the forensic pathologist were identified. Intoxications where zopiclone contributed to the cause of death were included in the study. The Swedish Prescribed Drug Register was utilized to examine whether the included cases were prescribed zopiclone or not.

RESULTS

In total 7320 fatal intoxications underwent a forensic autopsy during the study period, 573 of them were caused by zopiclone. Among the zopiclone fatalities, 87% (n = 494) had a prescription for zopiclone, and 8% (n = 43) were monointoxications. Most fatalities, 62% (n = 354) were suicides, and zopiclone was involved in about 17% (n = 354) of all intoxication suicides in Sweden. Women were significantly (p < 0.01) overrepresented in suicides with zopiclone, comprising 56% (n = 291) of fatalities. The median age was 55 years among zopiclone intoxications compared with 44 years amongst all fatal intoxications.

CONCLUSION

This study demonstrates that the toxicity of zopiclone can be lethal both in combination with other substances and on its own. Most individuals dying in fatal zopiclone intoxications were prescribed zopiclone, which potentially indicates that a more restrictive prescribing rate could prevent future intoxication deaths, especially when caring for patients with an increased suicide risk.

Postmortem metabolomics as a high-throughput cause-of-death screening tool for human death investigations

Autopsy rates are declining globally, impacting cause-of-death (CoD) diagnoses and quality control. Postmortem metabolomics was evaluated for CoD screening using 4,282 human cases, encompassing CoD groups: acidosis, drug intoxication, hanging, ischemic heart disease (IHD), and pneumonia. Cases were split 3:1 into training and test sets. High-resolution mass spectrometry data from femoral blood were analyzed via orthogonal-partial least squares discriminant analysis (OPLS-DA) to discriminate CoD groups. OPLS-DA achieved an R2 = 0.52 and Q2 = 0.30, with true-positive prediction rates of 68% and 65% for training and test sets, respectively, across all groups. Specificity-optimized thresholds predicted 56% of test cases with a unique CoD, average 45% sensitivity, and average 96% specificity. Prediction accuracies varied: 98.7% for acidosis, 80.5% for drug intoxication, 81.6% for hanging, 73.1% for IHD, and 93.6% for pneumonia. This study demonstrates the potential of large-scale postmortem metabolomics for CoD screening, offering high specificity and enhancing throughput and decision-making in human death investigations.

Rilmazafone: A designer benzodiazepine pro-drug involved in fatal intoxications

Rilmazafone is a pro-drug that can be prescribed in Japan to treat insomnia. Rilmazafone metabolizes into active compounds by a ring closure resulting in a triazolo benzodiazepine structure similar to alprazolam. In mid-2022, the National Board of Forensic Medicine in Sweden were requested to investigate two separate deaths with the suspected use of pagoclone. Packages labeled "Pagoclone" were found at each scene that was suspected to contain rilmazafone based on website information. During screening by high resolution mass spectrometry, rilmazafone metabolites were presumptively identified. Due to the lack of reference material for the active metabolites, the metabolites were synthesized in house and quantification of the compounds identified in the two autopsy cases was prompted. In Case 1, femoral blood concentrations of 7.9, 65 and 170 ng/g of the metabolites rilmazolam, N-desmethyl rilmazolam and di-desmethyl rilmazolam, respectively, were detected. Additional toxicological findings included the medications haloperidol, alimemazine, fluoxetine, olanzapine and acetaminophen. In Case 2, femoral blood concentrations of 1.7, 1.4 and 70 ng/g of rimazolam, N-desmethyl rilmazolam and di-desmethyl rilmazolam, respectively, were detected. Additional toxicological findings included loperamide, alimemazine and pregabalin. The intake of rilmazafone was determined as the cause of death in Case 1 and contributed in the Case 2.

Validation of a non-targeted method devoted to identification and quantitation of toxicologically relevant compounds in plasma with HRMS

The objective of this study was to develop and validate a simple method using liquid chromatography hyphenated to high resolution mass spectrometry (HRMS) allowing both the performance of a non-targeted screening and the simultaneous quantification of 29 compounds of interest in clinical and forensic toxicology. Extraction was done with QuEChERS salts and acetonitrile, after addition of internal standard to 200 μL of human plasma samples. The mass spectrometer was an Orbitrap, with a heated electrospray ionization (HESI) probe. The analyses were carried out in full scan experiment with a nominal resolving power of 60,000 FWHM within the 125-650 m/z mass range, followed by four cycles of data dependent analysis (DDA) with a mass resolution of 16,000 FWHM. The untargeted screening was evaluated using 132 compounds, mean limit of identification (LOI) was 8.8 ng/mL (min = 0.05 ng/mL, max = 500 ng/mL) and mean limit of detection (LOD) was 0.25 ng/mL (min = 0.05 ng/mL, max = 5 ng/mL). The method was linear in the 5 to 500 ng/mL range (0.5 to 50 ng/mL for cannabinoids, 6-acetylmorphine and buprenorphine) with correlation coefficients > 0.99, intra- and inter-day accuracy and precision were < 15% for all compounds. The method was successfully applied to 31 routine samples.

Establishment and application of a screening method for 354 organic toxicants in blood and urine with high-performance liquid chromatography-high-resolution orbitrap mass spectrometry

A rapid and sensitive high-performance liquid chromatography-high-resolution orbitrap mass spectrometry method was developed for the simultaneous screening of 354 organic poisons and metabolites in blood and urine, including drugs, medications, pesticides, rodenticides, veterinary drugs, alkaloids, and mycotoxins with a multi-toxicant chromatography-mass spectrometry information library. The method and library showed good prospects in clinical poisoning screening and forensic toxicological identification. Blood and urine samples were extracted successively with ethyl acetate in acidic and alkaline conditions; then, the extract was blown to nearly dry by nitrogen gas and redissolved with methanol-aqueous solution (v:v, 50:50), and the dissolved solution was analyzed by LC-MS/MS after filtering. Precursor ions' m/z was set for identification, retention time, fragment ions, and isotopic pattern which were used for confirmation. No interference peaks were found in the blank samples, showing good specificity. The LODs of toxicants in urine and blood were 1.00×10^-3-50.0 ng/mL and 2.07×10^-3-50.0 ng/mL, respectively, while the LOQs were 3.30×10^-3-1.67×10² ng/mL and 6.91×10^-3-1.67×10² ng/mL. The intra-day precision and inter-day precision of urine samples were 2.31-9.13% and 4.75-12.3%, respectively, which were 1.92-10.8% and 2.01-12.1% in blood samples. The established method was applied to analyze 9 cases of clinical poisoning patients, and bromadiolone, carbofuran, and amanitins were detected, respectively. A total of 382 biospecimens from drug abusers were analyzed with the proposed method, which indicated that some drugs were detected in 62 cases, mainly including methamphetamine, heroin, and MDMA. The results were consistent with the information from traditional liquid chromatography-triple quadrupole mass spectrometry.

Postmortem Metabolomics of Insulin Intoxications and the Potential Application to Find Hypoglycemia-Related Deaths

Postmortem metabolomics can assist death investigations by characterizing metabolic fingerprints differentiating causes of death. Hypoglycemia-related deaths, including insulin intoxications, are difficult to identify and, thus, presumably underdiagnosed. This investigation aims to differentiate insulin intoxication deaths by metabolomics, and identify a metabolic fingerprint to screen for unknown hypoglycemia-related deaths. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry data were obtained from 19 insulin intoxications (hypo), 19 diabetic comas (hyper), and 38 hangings (control). Screening for potentially unknown hypoglycemia-related deaths was performed using 776 random postmortem cases. Data were processed using XCMS and SIMCA. Multivariate modeling revealed group separations between hypo, hyper, and control groups. A metabolic fingerprint for the hypo group was identified, and analyses revealed significant decreases in 12 acylcarnitines, including nine hydroxylated-acylcarnitines. Screening of random postmortem cases identified 46 cases (5.9%) as potentially hypoglycemia-related, including six with unknown causes of death. Autopsy report review revealed plausible hypoglycemia-cause for five unknown cases. Additionally, two diabetic cases were found, with a metformin intoxication and a suspicious but unverified insulin intoxication, respectively. Further studies are required to expand on the potential of postmortem metabolomics as a tool in hypoglycemia-related death investigations, and the future application of screening for potential insulin intoxications.

Liquid Chromatography High Resolution Mass Spectrometry in Forensic Toxicology: What Are the Specifics of Method Development, Validation and Quality Assurance for Comprehensive Screening Approaches?

The use of High Resolution Mass Spectrometry (HRMS) has increased over the past decade in clinical and forensic toxicology, especially for comprehensive screening approaches. Despite this, few guidelines of this field have specifically addressed HRMS issues concerning compound identification, validation, measurement uncertainty and quality assurance. To fully implement this technique, certainly in an era in which the quality demands for laboratories are ever increasing due to various norms (e.g. the International Organization for Standardization's ISO 17025), these specific issues need to be addressed. This manuscript reviews 26 HRMS-based methods for qualitative systematic toxicological analysis (STA) published between 2011 and 2021. Key analytical data such as samples matrices, analytical platforms, numbers of analytes and employed mass spectral reference databases/libraries as well as the studied validation parameters are summarized and discussed. The article further includes a critical review of targeted and untargeted data acquisition approaches, available HRMS reference databases and libraries as well as current guidelines for HRMS data interpretation with a particular focus on identification criteria. Moreover, it provides an overview on current recommendations for the validation and determination measurement uncertainty of qualitative methods. Finally, the article aims to put forward suggestions for method development, compound identification, validation experiments to be performed, and adequate determination of measurement uncertainty for this type of wide-range qualitative HRMS-based methods.

Postmortem Metabolomics Reveal Acylcarnitines as Potential Biomarkers for Fatal Oxycodone-Related Intoxication

Postmortem metabolomics has recently been suggested as a potential tool for discovering new biological markers able to assist in death investigations. Interpretation of oxycodone concentrations in postmortem cases is complicated, as oxycodone tolerance leads to overlapping concentrations for oxycodone intoxications versus non-intoxications. The primary aim of this study was to use postmortem metabolomics to identify potential endogenous biomarkers that discriminate between oxycodone-related intoxications and non-intoxications. Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry data from 934 postmortem femoral blood samples, including oxycodone intoxications and controls positive and negative for oxycodone, were used in this study. Data were processed and evaluated with XCMS and SIMCA. A clear trend in group separation was observed between intoxications and controls, with a model sensitivity and specificity of 80% and 76%. Approximately halved levels of short-, medium-, and long-chain acylcarnitines were observed for oxycodone intoxications in comparison with controls (p < 0.001). These biochemical changes seem to relate to the toxicological effects of oxycodone and potentially acylcarnitines constituting a biologically relevant biomarker for opioid poisonings. More studies are needed in order to elucidate the potential of acylcarnitines as biomarker for oxycodone toxicity and their relation to CNS-depressant effects.

The metabolism of the synthetic cannabinoids ADB-BUTINACA and ADB-4en-PINACA and their detection in forensic toxicology casework and infused papers seized in prisons

Early warning systems detect new psychoactive substances (NPS), while dedicated monitoring programs and routine drug and toxicology testing identify fluctuations in prevalence. We report the increasing prevalence of the synthetic cannabinoid receptor agonist (SCRA) ADB-BUTINACA (N-[1-amino-3,3-dimethyl-1-oxobutan-2-yl]-1-butyl-1H-indazole-3-carbox-amide). ADB-BUTINACA was first detected in a seizure in Sweden in 2019, and we report its detection in 13 routine Swedish forensic toxicology cases soon after. In January 2021, ADB-BUTINACA was detected in SCRA-infused papers seized in Scottish prisons and has rapidly increased in prevalence, being detected in 60.4% of the SCRA-infused papers tested between January and July 2021. In this work, ADB-BUTINACA was incubated with human hepatocytes (HHeps), and 21 metabolites were identified in vitro, 14 being detected in authentic case samples. The parent drug and metabolites B9 (mono-hydroxylation on the n-butyl tail) and B16 (mono-hydroxylation on the indazole ring) are recommended biomarkers in blood, while metabolites B4 (dihydrodiol formation on the indazole core), B9, and B16 are suitable biomarkers in urine. ADB-4en-PINACA (N-[1-amino-3,3-dimethyl-1-oxobutan-2-yl]-1-[pent-4-en-1-yl]-1H-indazole-3-carboxamide) was detected in Scottish prisons in December 2020, but, unlike ADB-BUTINACA, prevalence has remained low. ADB-4en-PINACA was incubated with HHeps, and 11 metabolites were identified. Metabolites E3 (dihydrodiol formed in the tail moiety) and E7 (hydroxylation on the linked/head group) are the most abundant metabolites in vitro and are suggested as urinary biomarkers. The in vitro potencies of ADB-BUTINACA (EC₅₀ , 11.5 nM and ADB-4en-PINACA (EC₅₀ , 11.6 nM) are similar to that of MDMB-4en-PINACA (EC₅₀ , 4.3 nM). A third tert-leucinamide SCRA, ADB-HEXINACA was also detected in prison samples and warrants further investigation.

Heroin-Related Compounds and Metabolic Ratios in Postmortem Samples Using LC-MS-MS

Analysis of postmortem samples with the presence of morphine can sometimes be challenging to interpret. Tolerance complicates interpretation of intoxications and causes of death due to overlap in therapeutic and fatal concentrations. Determination of metabolites and metabolic ratios can potentially differentiate between abstinence, continuous administration, and perhaps time of administration. The purpose of this study was to (a) develop and validate a method for quantitation of morphine-3β-D-glucuronide, morphine-6β-D-glucuronide, normorphine, codeine-6β-D-glucuronide, norcodeine, codeine, 6-acetylmorphine, and ethylmorphine in urine using liquid chromatography–tandem mass spectrometry; (b) apply the method to opiate related deaths; (c) compare metabolic ratios in urine in different causes of death (CoD) and after different drug intakes and (d) compare heroin intoxications in rapid and delayed deaths. Validation parameters such as precision, bias, matrix effects, stability, process efficiency, and dilution integrity were assessed and deemed acceptable. Lower limits of quantitation ranged from 0.01–0.2 μg/mL for all analytes. Autopsy cases (n=135) with paired blood and urine samples were analyzed. Cases were divided into three groups based on CoD; opiate intoxication, intoxication with other drugs than opiates, and other CoD. The cases were classified by intake: codeine (n=42), heroin (n=36), morphine (n=49), and ethylmorphine (n=3). Five cases were classified as mixed intakes and excluded. Heroin intoxications (n=35) were divided into rapid (n=15) or delayed (n=20) deaths. Parent drug groups were compared using metabolic ratio morphine-3β-D-glucuronide/morphine and significant differences were observed between codeine vs morphine (p=0.005) and codeine vs heroin (p≤0.0001). Urine and blood concentrations, and metabolic ratios in rapid and delayed heroin intoxications were compared and determined a significant difference for morphine (p=0.001), codeine (p=0.009), 6-acetylmorphine (p=0.02) in urine, and morphine (p=0.02) in blood, but there was no significant difference (p=0.9) between metabolic ratios. Morphine-3β-D-glucuronide results suggested a period of abstinence prior to death in 25% of the heroin intoxications.

Post-Mortem Metabolomics: A Novel Approach in Clinical Biomarker Discovery and a Potential Tool in Death Investigations

Metabolomics can be defined as the scientific field aiming at characterizing all low-weight molecules (so-called metabolites) in a biological system. At the time of death, the level and type of metabolites present will most likely reflect the events leading up to death.In this proof of concept study, we investigated the potential of post-mortem metabolomics by identifying post-mortem biomarkers, correlated these identified biomarkers with those reported in clinical metabolomics studies, and finally validated the models predictability of unknown autopsy cases. In this post-mortem metabolomics setting, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry data from 404 post-mortem samples, including pneumonia cases and control cases, were processed using XCMS (R). Potential biomarkers were evaluated using principal component analysis and orthogonal partial least squares-discriminant analysis. Biomarkers were putatively annotated using an in-house database and the online databases METLIN and HMDB. The results showed that clear group separation was observed between pneumonia cases and control cases. The metabolites responsible for group separation belonged to a broad set of biological classes, such as amino acids, carnitines, lipids, nicotinamides, nucleotides, and steroids. Many of these metabolites have been reported as important in clinical manifestation of pneumonia. For the unknown autopsy cases, the sensitivity and specificity were 86 and 84%, respectively. This study successfully investigated the robustness and usability of post-mortem metabolomics in death investigations. The identified post-mortem biomarkers correlated well with biomarkers reported and identified through clinical research.

Oxycodone findings and CYP2D6 function in postmortem cases

Genetic disposition can cause variation in oxycodone pharmacokinetic characteristics and decrease or increase the expected clinical response. In forensic medicine, determination of cause of death or assessing time between drug intake and death can be facilitated by knowledge of parent and metabolite concentrations. In this study, the aim was to investigate if CYP2D6 genotyping can facilitate interpretation by investigating the frequency of the four CYP2D6 phenotypes, poor metabolizer, intermediate metabolizer, extensive metabolizer, and ultra-rapid metabolizer in postmortem cases, and to study if the CYP2D6 activity was associated with a certain cause of death, concentration, or metabolic ratio. Cases positive for oxycodone in femoral blood (n = 174) were genotyped by pyrosequencing for CYP2D6*3, *4, and *6 and concentrations of oxycodone, noroxycodone, oxymorphone, and noroxymorphone were determined by LC-MS/MS (LLOQ 0.005 µg/g). Digital droplet PCR was used to determine the copy number variation for CYP2D6*5. Cases were categorized by cause of death. It was found that poor and intermediate CYP2D6 metabolizers had significantly higher oxycodone and noroxycodone concentrations compared to extensive and ultra-rapid metabolizers. CYP2D6 phenotype were equally distributed between cause of death groups, showing that no phenotype was overrepresented in any of the cause of death groups. We also found that the concentration ratio between oxymorphone and oxycodone depended on the CYP2D6 activity when death was unrelated to intoxication. In general, a low metabolite to parent ratio indicate an acute intake. By using receiver operating characteristic (ROC) analysis, we conclude that an oxymorphone/oxycodone ratio lower than 0.075 has a high sensitivity for separating intoxications with oxycodone from other intoxications and non-intoxications. However, the phenotype needs to be known to reach a high specificity. Therefore, the ratio should not be used as a biomarker on its own to distinguish between different causes of death but needs to be complemented by genotyping.

Oxycodone Concentrations and Metabolic Ratios in Femoral Blood from Fatal Intoxications and Other Causes of Death using LC-MS-MS

Oxycodone (OC) is an opioid with strong analgesic effects widely used to treat acute and chronic pain. Interpretation of OC concentrations in postmortem cases is complicated due to tolerance and overlapping concentrations for fatal and non-fatal levels. In this study, our aim was to develop and validate a method for OC and its three metabolites: noroxycodone (NOC), oxymorphone (OM) and noroxymorphone (NOM) in postmortem femoral blood. Our goal was to define reference concentrations for intoxications and non-intoxications and investigate metabolic ratios in different causes of death. A rapid LC-MS-MS method using protein-precipitated postmortem blood was developed. Lower limit of quantitation was 0.005 μg/g blood for all analytes; upper limit of quantitation was 1.0 μg/g for OC and NOC and 0.25 μg/g for OM and NOM. The method displayed high precision (3.3-7.7%) and low bias (-0.3 to 12%). In total, 192 cases were analyzed and concentrations ranged from 0.005 to 13 μg/g for OC, 0.005 to 2.0 μg/g for NOC, 0.005 to 0.24 μg/g for OM, and 0.005 to 0.075 μg/g for NOM. We found a significant difference in OC concentration between the cases where OC contributed and those where it did not. In spite of that, we do not recommend the use of a specific blood concentration to distinguish fatal intoxications. Instead, the percentiles from our data set suggest that concentrations >0.2 μg/g are likely to have contributed to toxicity, but that concentrations as high as 0.3 might be tolerated without toxic effects. In addition, we also found that a low NOC/OC ratio could point toward an acute fatal intoxication. In conclusion, the OC concentration alone may not be sufficient to diagnose a fatal intoxication.

Methadone-related deaths among youth and young adults in Sweden 2006-15

AIMS

To identify methadone-related deaths and determine the prevalence among youth and young adults in Sweden 2006-15.

DESIGN, SETTING AND PARTICIPANTS

National retrospective registry study comparing data from all forensic autopsy examinations and toxicology cases involving methadone during 2006-15 in individuals aged 15-29 years with police records, previous pharmaceutical prescriptions and health-care episodes.

MEASUREMENTS

Multinomial logistic regression. To assess the factors contributing to the deaths, we compared individuals with and without previous substance use treatment and opioid use-related diagnoses with regard to previous opioid agonist treatment (OAT), psychiatric care and previous pain medication. To assess the circumstances of deaths, we analyzed the presence of other drugs and other factors at time of death.

FINDINGS

We identified 269 methadone-related deaths, and the rate increased during the study period. Seventy-two (27%) cases had not previously received substance use treatment, 112 (42%) had received treatment but had no opioid use-related diagnosis and 85 (32%) had received treatment and had an opioid use-related diagnosis. In total, only 10 individuals had been prescribed methadone during the year before death. Prescriptions of benzodiazepines (60%), antidepressants (62%) and opioids for pain (22%) the year before death were common. Most deaths occurred during sleep with a time lag from ingestion of methadone.

CONCLUSION

Prescription opioid- and methadone-related deaths increased in the group aged 15-29 years in Sweden between 2006 and 2015. Exposure to non-prescribed methadone and prescribed benzodiazepines, antidepressants and opioids for pain appears to be common in drug-related deaths in youth and young adults in Sweden.

Comprehensive UHPLC-HR-MSE screening workflow optimized for use in routine laboratory medicine: Four workflows in one analytical method

A comprehensive HR-MS screening can be used to identify thousands of drugs from a single analysis, which makes it a valuable tool for broad-scope component-resolved toxicological analysis. However, it is common practice in clinical toxicology to perform restricted data analysis to avoid examining and/or reporting data not requested for examination. In this study, a HR-MS screening workflow was developed to allow a comprehensive toxicological evaluation, but also restricted and levelled data analysis to fit in a clinical setting. Following precipitation and reconstitution, samples were injected on an UHPLC-HR-MS and data were analyzed with the data processing software UNIFI. Analytical validation of 38 selected drugs of abuse (DoA), included determination of matrix effect, recovery, process efficiency, and limit of identification (LOI). The method was tested on 49 authentic samples and matrix-matched ranges of calibrators for 95 drugs. The LOI ranged from 0.3 to 1426.7 ng mL^-1 for most analytes which was within expected concentration range for authentic samples with THC-COOH (>1722.0 ng mL^-1) and morphine (1426.7 ng mL^-1) as notable exceptions. Four individual screening workflows were developed: 1) a targeted workflow to serve as orthogonal identification of the 38 selected DOAs from another in-house method, 2) a general toxicology workflow, 3) an extended toxicology workflow including new psychoactive substances (NPS), and 4) a workflow for NPS based on the online HighResNPS library. Our study presents a comprehensive LC-HR-MS toxicology screening method optimized for laboratory medicine. The workflow allows for levelled data reviewing when requested without compromising the ability to perform full toxicological analyses.

Acute onset heart failure due to reverse type Takotsubo cardiomyopathy caused by a single dose of 4-Fluoroamphetamine in a healthy young individual

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4-Fluoroamphetamine (4-FA) is a popular new psychoactive stimulant that is used for recreational purposes.

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A single dose of 4-FA can lead to reverse type Takotsubo cardiomyopathy with cardiogenic shock.

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4-FA use can cause a very sudden onset of severe symptoms.

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Due to mild and late onset of effect, 4-FA users have the tendency to take an extra dose.

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Phosphodiesterase-3-inhibitors are effective for amphetamine type stimulant induced Takotsubo cardiomyopathy.

Introduction

4-fluoroamphetamine (4-FA) is a novel psychoactive stimulant with a global presence on the drug market. Despite the popularity of 4-FA, data on severe adverse effects are scarce. We present a case of laboratory confirmed 4-FA mono intoxication causing acute heart failure due to a reverse type Takotsubo cardiomyopathy.

Case

A 20-year-old male with no previous medical history and no reported previous drug use, presented to the emergency department (ED) with complaints of headache, nausea and vomiting, approximately 4.5 h after the ingestion of a single 4-FA pill. After 30 min his condition deteriorated with severe hypertension, tachycardia and respiratory failure. Echocardiography showed a reverse type Takotsubo cardiomyopathy. The patient was successfully treated with mechanical ventilation, a phosphodiesterase-3-inhibitor (PDE3-inhibitor) and diuretics. Three months after hospital admission, the patient was free of complaints and his left ventricular function fully recovered.

Conclusion

Recreational use of 4-FA may result in acute onset life-threatening cardiorespiratory toxicity, preceded by severe hypertension, even in drug-naïve patients without any medical history. Emergency physicians and cardiologists should be cautious not to underestimate life-threatening 4-FA complications.

MASS SPECTROMETRY ANALYSIS OF DRUGS OF ABUSE: CHALLENGES AND EMERGING STRATEGIES

Mass spectrometry has been the "gold standard" for drugs of abuse (DoA) analysis for many decades because of the selectivity and sensitivity it affords. Recent progress in all aspects of mass spectrometry has seen significant developments in the field of DoA analysis. Mass spectrometry is particularly well suited to address the rapidly proliferating number of very high potency, novel psychoactive substances that are causing an alarming number of fatalities worldwide. This review surveys advancements in the areas of sample preparation, gas and liquid chromatography-mass spectrometry, as well as the rapidly emerging field of ambient ionization mass spectrometry. We have predominantly targeted literature progress over the past ten years and present our outlook for the future. © 2020 Periodicals, Inc. Mass Spec Rev.

The unknown known: non-cardiogenic pulmonary edema in amlodipine poisoning, a cohort study

Context: Amlodipine is the most common calcium channel blocker (CCB) on the Swedish market, and poison center (PC) consultations for amlodipine overdoses are increasing. The clinical picture is dominated by vasodilation with relative preservation of cardiac function. CCBs selectively dilate vessels on the afferent side of the capillary network which, in states of preserved or increased blood flow may lead to edema formation, including non-cardiogenic pulmonary edema (NCPE). This complication has been considered rare in CCB poisoning. In this cohort study of nineteen amlodipine poisonings with high amlodipine blood levels, the incidence and clinical significance of NCPE in severe amlodipine poisoning are explored.Methods: During 2017-2018 the Swedish PC prospectively encouraged the gathering of blood samples in amlodipine poisonings with symptoms requiring treatment with inotropes or vasopressors. Samples were sent by mail to the Forensic Toxicology Division at the Swedish National Board of Forensic Medicine for screening and quantification of relevant toxicants. Patients with blood amlodipine levels >0.25 µg/mL were included in a cohort whose case details were gathered from medical records and PC-case notes with a special focus on signs of NCPE.Results: Nineteen patients met the blood amlodipine inclusion criteria. Four (21%) died and one patient was treated with VA-ECMO. Nine patients developed NCPE defined as a need for positive pressure ventilation (PPV) while having an echocardiographically normal left ventricular function.Conclusion: In this prospective cohort study of consecutive and analytically confirmed significant amlodipine poisonings NCPE was a common finding occurring in 47% of the whole cohort and in 64% of patients who did not go on to develop complete hemodynamic collapse.

Metformin - Postmortem fatal and non-fatal reference concentrations in femoral blood and risk factors associated with fatal intoxications

BACKGROUND & OBJECTIVES

To improve the interpretation of fatal intoxications by establishing fatal and non-fatal reference concentrations of metformin in postmortem femoral blood and to further evaluate risk factors associated with fatal metformin intoxication.

METHODS

All forensic autopsies in Sweden where metformin was detected in femoral blood 2011-2016 were identified in the National Board of Forensic Medicine databases (NFMD). The cases were classified as single substance intoxications, A (n = 22), multiple substance intoxications, B (N = 7) and postmortem controls, C (N = 13). The control group consisted of cases where metformin was detected, but the cause of death excluded the incapacitation by metformin or other substances. Strict inclusion criteria were used, and all postmortem cases were assessed by two independent reviewers. All other cases where the inclusion criteria of groups A-C where not met formed group O (N = 78). The forensic findings logged in the NFMD where linked to national registers whereby information on comorbidities, dispensed drugs and clinical data could be obtained.

RESULTS

The mean age was 66 ± 10 years in the total study population and did not differ between the groups. The proportion of men was 64% in group A, 71% in B, 77% in C and 74% in group O. The median values of metformin in group A (48.5 μg/g; range 13.0-210 μg/g) and B (21.0 μg/g; range 4.40-95.0 μg/g) were significantly (p < 0.001 and p = 0.015 respectively) higher than those of the control group C (2.30 μg/g ; range 0.70-21.0 μg/g). The median concentration of metformin in group A and B was also significantly higher than in group O (4.60 μg/g; range 0.64-54.0 μg/g) (p < 0.001 and p = 0.040 respectively). The results suggest that intoxication with metformin as a cause of death should be considered when the postmortem femoral blood level exceeds about 10 μg/g, although higher levels may be seen in postmortem in cases without incapacitation. The metformin intoxication was confirmed to be intentional in 23% (n = 5) of the single intoxications. Underlying factors identified as important for the remaining fatal metformin intoxications included living alone, any contraindication for the use of metformin, known alcohol abuse and a history of stroke or cardiovascular disease.

CONCLUSIONS

The reported post mortem femoral blood concentrations of metformin can hopefully contribute to a better interpretation of results in suspected poisonings and obscure cases. Living in a single household, history of cardiovascular disease and contraindications, predominantly alcohol abuse, were associated with fatal metformin intoxication.

Adherence to psychotropic medication in completed suicide in Sweden 2006-2013: a forensic-toxicological matched case-control study

OBJECTIVE

To investigate the influence of adherence to psychotropic medications upon the risk of completed suicide by comparing person-level prescriptions and postmortem toxicological findings among complete-suicide cases and non-suicide controls in Sweden 2006-2013.

METHODS

Using national registries with full coverage on dispensed prescriptions, results of medico-legal autopsies, causes of death, and diagnoses from inpatient care, estimated continuous drug use for 30 commonly prescribed psychotropic medications was compared with forensic-toxicological findings. Subjects who had died by suicide (cases) were matched (1:2) with subjects who had died of other causes (controls) for age, sex, and year of death. Odds ratios were calculated using logistic regression to estimate the risk of completed suicide conferred by partial adherence and non-adherence to pharmacotherapy. Adjustments were made for previous inpatient care and the ratio of initiated and discontinued dispensed prescriptions, a measure of the continued need of treatment preceding death.

RESULTS

In 5294 suicide cases and 9879 non-suicide controls, after adjusting for the dispensation ratio and other covariates, partial adherence and non-adherence to antipsychotics were associated with 6.7-fold and 12.4-fold risks of completed suicide, respectively, whereas corresponding risk estimates for antidepressant treatment were not statistically significant and corresponding risk increases for incomplete adherence to antidepressant treatment were lower (1.6-fold and 1.5-fold, respectively) and lacked statistical significance.

CONCLUSION

After adjustment for the need of treatment, biochemically verified incomplete adherence to antipsychotic pharmacotherapy was associated with markedly increased risks of completed suicide.

In Vitro and In Vivo Metabolite Identification Studies for the New Synthetic Opioids Acetylfentanyl, Acrylfentanyl, Furanylfentanyl, and 4-Fluoro-Isobutyrylfentanyl

New fentanyl analogs have recently emerged as new psychoactive substances and have caused numerous fatalities worldwide. To determine if the new analogs follow the same metabolic pathways elucidated for fentanyl and known fentanyl analogs, we performed in vitro and in vivo metabolite identification studies for acetylfentanyl, acrylfentanyl, 4-fluoro-isobutyrylfentanyl, and furanylfentanyl. All compounds were incubated at 10 μM with pooled human hepatocytes for up to 5 h. For each compound, four or five authentic human urine samples from autopsy cases with and without enzymatic hydrolysis were analyzed. Data acquisition was performed in data-dependent acquisition mode during liquid chromatography high-resolution mass spectrometry analyses. Data was analyzed (1) manually based on predicted biotransformations and (2) with MetaSense software using data-driven search algorithms. Acetylfentanyl, acrylfentanyl, and 4-fluoro-isobutyrylfentanyl were predominantly metabolized by N-dealkylation, cleaving off the phenethyl moiety, monohydroxylation at the ethyl linker and piperidine ring, as well as hydroxylation/methoxylation at the phenyl ring. In contrast, furanylfentanyl's major metabolites were generated by amide hydrolysis and dihydrodiol formation, while the nor-metabolite was minor or not detected in case samples at all. In general, in vitro results matched the in vivo findings well, showing identical biotransformations in each system. Phase II conjugation was observed, particularly for acetylfentanyl. Based on our results, we suggest the following specific and abundant metabolites as analytical targets in urine: a hydroxymethoxy and monohydroxylated metabolite for acetylfentanyl, a monohydroxy and dihydroxy metabolite for acrylfentanyl, two monohydroxy metabolites and a hydroxymethoxy metabolite for 4-fluoro-isobutyrylfentanyl, and a dihydrodiol metabolite and the amide hydrolysis metabolite for furanylfentanyl.

Targeted toxicological screening for acidic, neutral and basic substances in postmortem and antemortem whole blood using simple protein precipitation and UPLC-HR-TOF-MS

A broad targeted screening method based on broadband collision-induced dissociation (bbCID) ultra-performance liquid chromatography high-resolution time-of-flight mass spectrometry (UPLC-HR-TOF-MS) was developed and evaluated for toxicological screening of whole blood samples. The acidic, neutral and basic substances covered by the method were identified in postmortem and antemortem whole blood samples from forensic autopsy cases, clinical forensic cases and driving under the influence of drugs (DUID) cases by a reverse target database search. The screening method covered 467 substances. Validation was performed on spiked whole blood samples and authentic postmortem and antemortem whole blood samples. For most of the basic drugs, the established cut-off limits were very low, ranging from 0.25ng/g to 50ng/g. The established cut-off limits for most neutral and acidic drugs, were in the range from 50ng/g to 500ng/g. Sample preparation was performed using simple protein precipitation of 300μL of whole blood with acetonitrile and methanol. Ten microliters of the reconstituted extract were injected and separated within a 13.5min UPLC gradient reverse-phase run. Positive electrospray ionization (ESI) was used to generate the ions in the m/z range of 50-1000. Fragment ions were generated by bbCID. Identification was based on retention time, accurate mass, fragment ion(s) and isotopic pattern. A very sensitive broad toxicological screening method using positive electrospray ionization UPLC-HR-TOF-MS was achieved in one injection. This method covered basic substances, substances traditionally analyzed in negative ESI (e.g., salicylic acid), small highly polar substances such as beta- and gamma-hydroxybutyric acid (BHB and GHB, respectively) and highly non-polar substances such as amiodarone. The new method was shown to combine high sensitivity with a very broad scope that has not previously been reported in toxicological whole blood screening when using only one injection.

A data-independent acquisition workflow for qualitative screening of new psychoactive substances in biological samples

Identification of new psychoactive substances (NPS) is challenging. Developing targeted methods for their analysis can be difficult and costly due to their impermanence on the drug scene. Accurate-mass mass spectrometry (AMMS) using a quadrupole time-of-flight (QTOF) analyzer can be useful for wide-scope screening since it provides sensitive, full-spectrum MS data. Our article presents a qualitative screening workflow based on data-independent acquisition mode (all-ions MS/MS) on liquid chromatography (LC) coupled to QTOFMS for the detection and identification of NPS in biological matrices. The workflow combines and structures fundamentals of target and suspect screening data processing techniques in a structured algorithm. This allows the detection and tentative identification of NPS and their metabolites. We have applied the workflow to two actual case studies involving drug intoxications where we detected and confirmed the parent compounds ketamine, 25B-NBOMe, 25C-NBOMe, and several predicted phase I and II metabolites not previously reported in urine and serum samples. The screening workflow demonstrates the added value for the detection and identification of NPS in biological matrices.

Cardiovascular drug determination in bioanalysis: an update

The great impact of cardiovascular diseases in human health has led to the development of a huge number of drugs and therapies to improve the treatment of these diseases. Cardiovascular drug analysis in biological fluids constitutes an important challenge for analytical scientists. There is a clear need for reliable methods to carry out both qualitative and quantitative analysis in a short time of analysis. Different problems such as drug monitoring, analysis of metabolites, study of drugs interactions, drugs residues or degradation products, chiral separation, and screening and confirmation of drugs of abuse in doping control must be solved. New trends in sample preparation, instrumental and column technology advances in LC and innovations in MS are described in this work.

Fatal intoxications associated with the designer opioid AH-7921

AH-7921 (3,4-dichloro-N-[(1-dimethylamino)cyclohexylmethyl]benzamide) is a designer opioid with ∼80% of morphine's µ-agonist activity. Over a 6-month period, we encountered nine deaths where AH-7921 was involved and detected in blood from the deceased. Shortly after the last death, on August 1 2013, AH-7921 was scheduled as a narcotic and largely disappeared from the illicit market in Sweden. AH-7921 was measured by a selective liquid chromatography-MS-MS method and the concentrations of AH-7921 ranged from 0.03 to 0.99 µg/g blood. Six of our cases had other drugs of abuse on board and most had other medications such as benzodiazepines, antidepressants and analgesics. However, the other medicinal drugs encountered were present in postmortem therapeutic concentrations and unlikely to have contributed to death. In addition to the parent compound, we identified six possible metabolites where two N-demethylated dominated and four mono-hydroxylated were found in trace amounts in the blood. In conclusion, deaths with AH-7921 seem to occur both at low and high concentrations, probably a result of different tolerance to the drug. Hence, it is reasonable to assume that no sharp dividing line exists between lethal and non-lethal concentrations. Further, poly-drug use did not seem to be a major contributing factor for the fatal outcome.

Integration of microfluidic LC with HRMS for the analysis of analytes in biofluids: past, present and future

Capillary LC (cLC) coupled to MS has the potential to improve detection limits, address limited sample volumes and allow multiple analyses from one sample. This is particularly attractive in areas where ultrahigh assay sensitivity, low limits of detection and small sample volumes are becoming commonplace. However, implementation of cLC–MS in the bioanalytical–drug metabolism area had been hampered by the lack of commercial instrumentation and the need for experts to operate the system. Recent advances in microfabricated devices such as chip-cube and ion-key technologies offer the potential for true implementation of cLC in the modern laboratory including the benefits of the combination of this type of separation with high-resolution MS.

Multi-target screening of biological samples using LC–MS/MS: focus on chromatographic innovations

Multi-target screening of biological fluids is a key tool in clinical and forensic toxicology. A complete toxicological analysis encompasses the sample preparation, the chromatographic separation and the detection. The present review briefly covers the new trends in sample preparation and detection and mainly focuses on the chromatographic stage, since a lot of technical improvements have been proposed over the last years. Among them, columns packed with sub-2 μm fully porous particles and sub-3 μm core-shell particles allow for significant improvements of resolution and higher throughput. Even if reversed-phase LC remains the most widely used chromatographic mode for toxicological screening, hydrophilic interaction chromatography and supercritical fluid chromatography appear as promising alternatives for attaining orthogonal selectivity, retention of polar compounds, and enhanced MS sensitivity.

LC-QTOF-MS as a superior strategy to immunoassay for the comprehensive analysis of synthetic cannabinoids in urine

The objective of this study was to compare the performance of an immunoassay screening for synthetic cannabinoids with a newly developed confirmation method using liquid chromatography quadrupole time-of-flight mass spectrometry. The screening included metabolites from JWH-018, JWH-073, and AM-2201. The confirmation included metabolites from AM-2201, JWH-018, JWH-019, JWH-073, JWH-081, JWH-122, JWH-210, JWH-250, JWH-398, MAM-2201, RCS-4, and UR-144. The immunoassay was tested and found to have no cross-reactivity with UR-144 metabolites but considerable cross-reactivity with MAM-2201 and JWH-122 metabolites. Sensitivity and specificity for the immunoassay were evaluated with 87 authentic urine samples and found to be 87% and 82%, respectively. With a cutoff at 2 ng/ml, the confirmation showed 80 positive findings in 38 cases. The most common finding was JWH-122 5-OH-pentyl, followed by JWH-018 5-OH-pentyl. There were 9 findings of UR-144 metabolites and 3 of JWH-073 metabolites. In summary, the immunoassay performed well, presenting both high sensitivity and specificity for the synthetic cannabinoids present in the urine samples tested. The rapid exchange of one cannabinoid for another may pose problems for immunoassays as well as for confirmation methods. However, we consider time-of-flight mass spectrometry to be superior since new metabolites can be quickly included and identified.