Simultaneous determination of four antiepileptic drugs in human plasma samples using an ultra-high-performance liquid chromatography tandem mass spectrometry method and its application in therapeutic drug monitoring

International audienceTherapeutic drug monitoring of antiepileptic drugs is widely practiced to achieve optimal efficacy and avoid adverse side effects. We describe an ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC/MS/MS) method developed for the monitoring of four frequently prescribed antiepileptic drugs - lamotrigine, levetiracetam, oxcarbazepine and topiramate. The main pharmacologically active metabolite of oxcarbazepine (mono-hydroxy-derivative metabolite, MHD) was also quantified. After addition of internal standards and a simple stage of protein precipitation, plasmatic samples were analyzed on a C18 column. All antiepileptic drugs were separated and quantified in 6 min, without interference. A good linearity was observed all over the calibration range (r2 > 0.99), up to 20 μg/mL (40 μg/mL for MHD). The limit of quantification was 0.20 μg/mL (0.40 μg/mL for MHD) with precision and accuracy ranging from 1.0 to 2.1% and from 96.7 to 110.8%, respectively. Intra- and inter-day precision and accuracy values were within 15%. No significant matrix effect was observed for all analytes. Clinical application was successfully evaluated in 259 samples from patients treated for epilepsy or bipolar disorders. In conclusion, a rapid, specific and sensitive UHPLC/MS/MS method was developed and validated for simultaneous quantification of antiepileptic drugs, suitable for therapeutic drug monitoring in neurology and psychiatry

Unintentional cannabis poisoning in toddlers: A one year study in Marseille

International audienceFrance is the country with the highest prevalence of cannabis use in Europe, despite the fact that cannabis has not been legalized. This prevalence is still increasing along with THC content in cannabis products. In the meantime, unintentional cannabis poisoning by ingestion in toddlers is constantly rising. The aim of this study was to document children's cannabis poisoning biologically and clinically. Plasma and urine samples were extracted by solid phase extraction and analyzed by liquid chromatography coupled to tandem mass spectrometry. Children under 4 years old admitted in pediatric emergency departments for cannabis intoxication between February 1st 2019 and January 31st 2020 were included in this study. Twenty-six children were included (14 female and 12 male), the mean age was 17 months (10-41 months). THC, 11-OH-THC and THC-COOH plasma concentrations ranged from 2.9 to 93 ng/mL, 2.6-65 ng/mL and 29-914 ng/mL, respectively. The most frequent symptoms were drowsiness and hypotonia. Six critical cases were observed: 5 coma and 1 respiratory depression. All children having THC plasma concentrations over 60 ng/mL were in coma. Cannabis poisoning in toddlers become more frequent, 9 cases/year were reported in Marseille in 2007 and 26 cases/year in this study. There is a rising in severe clinical cases, particularly coma. These observations could be explained by an increase in THC content in cannabis products, and a trivialization of cannabis consumption. The unintentional ingestion of cannabis by children is a serious public health concern, and cannabis legalization could worsen this problem

Transdermal Nicotine Poisoning: A Rare Case Report of Occupational Exposure

International audienceWe report a case of accidental nicotine intoxication following transdermal exposure in a 22-year-old man with no medical history, who worked in a company manufacturing e-liquids for electronic cigarettes. He accidentally spilled 300 mL of pure nicotine solution (>99%) on his right leg without wearing protective clothing or a mask. Less than a minute later, he experienced dizziness, nausea, and headaches, followed by painful burning sensations in the affected area. He immediately removed his pants and washed his leg thoroughly with water. He presented to the emergency department two hours later, where he exhibited a respiratory rate of 25 cpm, a heart rate of 70 bpm, headaches, abdominal pain, pallor, and vomiting. He recovered without specific treatment five hours post-intoxication. Plasma levels of nicotine, cotinine, and hydroxycotinine were measured five hours after exposure using liquid chromatography-mass spectrometry. The concentrations found were 447 ng/mL for nicotine, 1254 ng/mL for cotinine, and 197 ng/mL for hydroxycotinine. Nicotine is an alkaloid that can be highly toxic, with doses of 30-60 mg being potentially fatal. Transdermal intoxication is rare, with very few cases reported in the literature. This case highlights the risk of acute intoxication through cutaneous exposure to nicotine-containing liquid products and the need for protective clothing when handling such products in a professional context

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

International audienceThe 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

Determination of Prenatal Substance Exposure Using Meconium and Orbitrap Mass Spectrometry

The aim of this study was to develop and to validate a toxicological untargeted screening relying on LC-HRMS in meconium including the detection of the four main classes of drugs of abuse (DoA; amphetamines, cannabinoids, opioids and cocaine). The method was then applied to 29 real samples. Analyses were performed with a liquid chromatography system coupled to a benchtop Orbitrap operating in a data-dependent analysis. The sample amount was 300 mg of meconium extracted twice by solid phase extraction following two distinct procedures. Raw data were processed using the Compound Discoverer 3.2 software (Thermo). The method was evaluated and validated on 15 compounds (6-MAM, morphine, buprenorphine, norbuprenorphine, methadone, EDDP, amphetamine, MDA, MDMA, methamphetamine, cocaine, benzoylecgonine, THC, 11-OH-THC, THC-COOH). Limits of detection were between 0.5 and 5 pg/mg and limits of identification between 5 and 50 pg/mg. Mean matrix effect was between −79 and −19% (n = 6) and mean overall recovery between 18 and 73% (n = 6) at 100 pg/mg. The application allows the detection of 88 substances, including 47 pharmaceuticals and 15 pharmaceutical metabolites, cocaine and its metabolites, THC and its metabolites, and natural (morphine, codeine) and synthetic (methadone, buprenorphine, tramadol, norfentanyl) opioids. This method is now used routinely for toxicological screening in high-risk pregnancie

Development and Validation of a Simple and Rapid Ultrahigh-Performance Liquid Chromatography Tandem Spectrometry Method for the Quantification of Hydroxychloroquine in Plasma and Blood Samples in the Emergency Context of SARS-CoV-2 Pandemic

International audienceTherapeutic drug monitoring of hydroxychloroquine (HCQ) has been recommended to optimize the treatment of patients with COVID-19. The authors describe an ultrahigh-performance liquid chromatography tandem spectrometry method developed in a context of emergency, to analyze HCQ in both human plasma and blood samples. After adding the labeled internal standard and simple protein precipitation, plasma samples were analyzed using a C18 column. Blood samples required evaporation before analysis. The total chromatographic run time was 4 minutes (including 1.5 minutes of column equilibration). The assay was linear over the calibration range (r2 > 0.99) and up to 1.50 mcg/mL for the plasma samples (5.00 mcg/mL for the blood matrix). The limit of quantification was 0.0150 mcg/mL for plasma samples (0.05 mcg/mL blood matrix) with accuracy and precision ranging from 91.1% to 112% and from 0.750% to 11.1%, respectively. Intraday and interday precision and accuracy values were within 15.0%. No significant matrix effect was observed in the plasma or blood samples. This method was successfully applied to patients treated for COVID-19 infection. A simple and rapid ultrahigh-performance liquid chromatography tandem spectrometry method adapted to HCQ therapeutic drug monitoring in the context of SARS-CoV-2 infection was successfully developed and validated