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Insulin glargine is a long‐acting insulin analog that is converted after enzymatic cleavage of the arginine pair of the β‐chain into its main metabolite M1 (21A‐Gly‐insulin), which is responsible for the hypoglycemic activity. In all the overdose cases described in the literature, only M1 concentrations have been reported, whereas insulin glargine was always absent or below the limit of quantitation. In this study, we present a case of suicide of a young nurse by injection of insulin glargine in which the parent molecule was found at a toxic concentration in blood. The determination and the discrimination of insulin glargine from human insulin and other synthetic analogs in the blood specimen were performed by liquid chromatography coupled to high‐resolution mass spectrometry (Waters XEVO G2‐XS QToF) and extraction after precipitation in the presence of bovine insulin (internal standard), with a mixture of acetonitrile/methanol +1% formic acid followed by purification on solid phase extraction cartridges C18. Glargine insulin tested highly positive in the blood with a concentration of 1.06 mg/L. Due to the difficulty in obtaining a M1 pure standard, the metabolite could not be dosed. This unique presence of the parent molecule, reported for the first time, can be explained by inter‐individual variability in the rate of conversion to metabolite. Intravenous injection versus subcutaneous injection can also explain the presence of insulin glargine. Finally, the dose injected may have been so high that saturation of the proteolytic enzymes responsible for conversion to M1 should have occurred. [ABSTRACT FROM AUTHOR]

Evidence of an insulin overdose is very complicated in the medico-legal field. The analysis and subsequent interpretation of results is complex, especially when treating postmortem blood samples. The instability of insulin, the special pre-analytical conditions and the absence of specific analytical methods has led most laboratories not to analyze insulin in their routine with a consequent underestimation of cases. This paper aims to assess the difficulties associated with the analytical characterization of insulin by describing a case that typically represents most of the inconveniences encountered following a suspected insulin overdose. The case concerns a man found dead at home by his brother. After an external examination, which did not reveal a specific cause of death, toxicological analysis was requested which did not reveal any substance of toxicological interest. Only 9 months later, it was reported to the toxicologist that the subject was diabetic, on insulin lispro treatment and that three empty syringes were found next to his body. Following analysis by LC-high-resolution mass spectrometry, the presence of insulin lispro at a concentration of 1.1 ng/mL, a therapeutic concentration, was evidenced. Despite the low concentration found, overdose cannot be excluded and this paper will describe the criteria evaluated to reach this conclusion. This case highlights that the interpretation of a postmortem insulin concentration is very complex and requires the evaluation of various elements including the circumstances of death, the subject's medical history, the interval between death and sampling and the sample storage. [ABSTRACT FROM AUTHOR]

Anabolic steroids are synthetic derivatives of testosterone, and their abuse can have numerous health consequences. Identification of this group of drugs has found applications in forensic toxicology, clinical situations, psychiatric disorders, and of course, anti‐doping violations. Although anabolic steroids are generally tested in urine and very occasionally in head hair, collectors can face the lack of standard specimens, and therefore, nail clippings can be the unique alternative choice. Although there is no possibility to perform segmental analyses using nail clippings, the window of drug detection is generally much longer in nail when compared to head hair (particularly in male subjects), that is, 3–8 months and 4–12 months for finger and toenail clippings, respectively. A new method was developed, including nail pulverization in a ball mill, sonication for 90 min in methanol, and a combination of liquid–liquid and solid‐phase extractions, followed by gas and liquid chromatography coupled to tandem mass spectrometry. To document the application of steroid testing in nail clippings, the authors present 6 authentic cases of abuse, involving stanozolol (7 and 24 pg/mg), nandrolone (6 pg/mg), trenbolone (26, 67, 81, and 89 pg/mg), drostanolone (8 and 11 pg/mg), and testosterone enanthate (14 pg/mg). Given concentrations were always in the low pg/mg range, the use of tandem mass spectrometry appears as a prerequisite. [ABSTRACT FROM AUTHOR]