Carbamazepine Overdose after Psychiatric Conditions: A Case Study for Postmortem Analysis in Human Bone.

Carbamazepine is the main option used as a preventive medication to treat bipolar disorder when there is no response to lithium. Carbamazepine toxicity is defined as serum levels greater than 12 µg/mL, with severe toxicity occurring over 40 µg/mL, reduced to 30 µg/mL when combined with pharmacological treatment, i.e., benzodiazepines or antidepressants. For these reasons, it is necessary to find a validated tool to determine carbamazepine levels in an autopsy to rule out suicide or to know if the death was a consequence of an adverse drug reaction (ADR), especially when only bones can be accessed. We have validated a tool to detect and quantify drug concentration in bone. Our results showed a peak for carbamazepine at minute 12 and a mass fragment of 193 m/z. This case study is the first time in the literature that carbamazepine has been detected and quantified in bone. These results demonstrate that carbamazepine can be detected in bone tissue from forensic cases, but almost more importantly, that the method proposed is valid, reliable, and trustworthy.

Effects of Polycyclic Aromatic Hydrocarbons on Lung Function in Children with Asthma: A Mediation Analysis.

Studies investigating the association between urinary Polycyclic Aromatic Hydrocarbons (PAHs) and asthma in children provided inhomogeneous results. We aimed to use Mediation Analysis to discover whether a link between urinary PAHs and lung function exists and if it might be ascribed to a direct or a symptom-mediated (indirect) effect in children with asthma. This single-center prospective study was conducted in Palermo, Italy, between March and July 2017 and involved 50 children with persistent mild-moderate asthma, aged 6-11 years. At each time visit (day 0, 30, 60, and 90), physical examination, spirometry, and urine collection for detection of urinary cotinine and PAHs were performed. A symptom score was computed. The sum of individually calculated molar mass of nine PAH metabolites (ΣPAH), naphthalene metabolites (ΣPAHn) and phenanthrene metabolites (ΣPAHp) were calculated. Three children withdrew from the study due to technical problems (n = 1) and adverse events (n = 2). PAHs indirect effects on FEV1 (ΣPAH: -0.011, p = 0.04; ΣPAHn: -0.011, p = 0.04; ΣPAHp: -0.012, p < 0.001) and FVC (ΣPAH: -0.012, p = 0.02; ΣPAHn: -0.0126, p = 0.02; ΣPAHp: -0.013, p < 0.001) were statistically significant. In conclusion, PAHs exposures have significant indirect (symptom-mediated) effects on lung function, emphasizing the role of PAHs-induced respiratory morbidity in decreasing lung function in children with asthma.

Postmortem Analysis of Benzodiazepines in Human Bone by Gas Chromatography-Mass Spectrometry.

A procedure based on gas chromatography-mass spectrometry was developed for the analysis of benzodiazepines (nordiazepam, oxazepam, lormetazepam, lorazepam, clonazepam, bromazepam and alprazolam) in postmortem human ribs. Powdered bone samples, including marrow remains inside, with the internal standard diazepam-d5 were subjected to enzymatic hydrolysis with 100 µL of ß-glucoronidase and were incubated in sodium hydroxide for 1 h in a 70°C oven. Samples underwent liquid phase extraction and ethyl acetate was used as eluent. Chromatography was performed on a fused silica capillary column and the selected-ion-monitoring mode was used for analytes determination. The method was validated in the range 0.1-0.5 ng/mg (depending on the benzodiazepine) to 100 ng/mg with average values of recovery, matrix effect and process efficiency ranged from 83.2 to 94.3%, from 97.3 to 102.1% and from 80.5 to 91.2%, respectively. The intra- and inter-day accuracy was <15%. The procedure was tested in rib specimens obtained during routine autopsies from 20 cases where these benzodiazepines were found in blood. Benzodiazepines were detected in the combined bone and marrow samples in 60% of cases. Lorazepam was detected in bone in the range of 0.3-0.7 ng/mg, nordiazepam at 1.3-4.2 ng/mg and oxazepam at 1.1-1.2 ng/mg. To our knowledge, this protocol for the simultaneous analysis of these benzodiazepines is the first performed and validated using human ribs.

Postmortem analysis of quetiapine and pregabalin in human bone.

In this study quetiapine and pregabalin were analyzed in human bones. A method previously developed for the determination of antidepressants in human bone was tested for the analysis of these two substances. Bones were pulverized and subjected to the extraction protocol, and after undergoing solid-phase extraction, samples were analyzed using gas chromatography-mass spectrometry. The assay was validated in the range 0.3-500 ng/mg, mean analytical recovery was 76.9% for quetiapine and 90.9% for pregabalin, matrix effect was 83% for quetiapine and 91% for pregabalin and process efficiency was 63.8% for quetiapine and 82.7% for pregabalin. The intra- and inter-day precision was below 3% in all cases and the intra- and inter-assay accuracy values were in almost all cases better than 12%. The validated method was then applied to bone samples from forensic cases. Drugs were detected in bone in 2 of the 3 blood positive cases. The approximate concentrations in bone were 40 ng/mg for pregabalin and 7 ng/mg for quetiapine. To our knowledge, this is the first time these substances were detected in bones. With this study the number of substances with a validated protocol to be used in human bones in case of necessity is expanded.

Development and Validation of a Method for the Analysis of Bisoprolol and Atenolol in Human Bone.

A method based on gas chromatography-mass spectrometry (GC-MS) is described for the determination of bisoprolol and atenolol in human bone. After the addition of lobivolol as internal standard, pulverized samples were incubated in acetonitrile for 1 h under ultrasounds. After adjusting the pH of the samples to 6, they were centrifuged, and the supernatants were subjected to solid phase extraction. Elution was achieved by using 3 mL of 2% ammonium hydroxide in 80:20 dichloromethane:isopropanol solution. Eluted samples were evaporated and derivatized. Chromatography was performed on a fused silica capillary column and analytes were determined in the selected-ion-monitoring (SIM) mode. The assay was validated in the range 0.1-0.3 ng/mg (depending on the drug) to 150 ng/mg, the mean absolute recoveries were 60% for bisoprolol and 106% for atenolol, the matrix effect was 69% for bisoprolol and 70% for atenolol and process efficiency was 41% for bisoprolol and 80% for atenolol. The intra- and inter-assay accuracy values were always better than 12%. The validated method was then applied to bone samples from two real forensic cases in which toxicological analysis in blood were positive for atenolol in the first case (0.65 µg/mL) and bisoprolol in the second case (0.06 µg/mL). Atenolol was found in bone samples from the corresponding case at the approximate concentration of 148 ng/mg and bisoprolol was found at 8 ng/mg.

Development and validation of a method for analysing of duloxetine, venlafaxine and amitriptyline in human bone.

A method based on gas chromatography-mass spectrometry (GC-MS) is described for the determination of venlafaxine, amitriptyline and duloxetine in human bone. Pulverized samples were incubated in methanol for 1 h under ultrasonication, after the addition of sertraline as internal standard. The samples were centrifuged, and the supernatants were evaporated. Samples were then resuspended in 0.1 M phosphate buffer pH 6 and subjected to solid phase extraction. Chromatography was performed on a fused silica capillary column and analytes were determined in the selected-ion-monitoring (SIM) mode. The assay was validated in the range 0.3-1 ng/mg (depending on the drug) to 500 ng/mg. The mean absolute recoveries ranged from 92.6% to 96.2%, the matrix effect from 76.9% to 103.3% and process efficiency from 74% to 95.9% depending on the analyte. The intra- and inter-assay accuracy values were always better than 20%. The validated method was then successfully applied to real bone samples from forensic cases in which toxicological analysis for these drugs in blood had been positive. Drugs were detected in bone in all blood positive results, the approximate concentrations being 36.4 ng/mg for amitriptyline, 19.3-3 ng/mg for duloxetine and 4.6-2 ng/mg for venlafaxine.

Development and validation of a gas chromatography-mass spectrometry method for opiates and cocaine in human bone.

A method based on gas chromatography-mass spectrometry (GC-MS) is described for the determination of opioids (6-monoacetylmorphine, morphine, methadone and tramadol) and cocaine and its major metabolite in human bone. After the addition of nalorphine as internal standard, pulverized samples were incubated in acetonitrile for 1 h under ultrasounds. After adjusting the pH of the samples to 6, they were subjected to solid phase extraction and the analytes were eluted using 2 ml of dichloromethane/isopropanol/ammonia (78:20:2). Chromatography was performed on a fused silica capillary column and analytes were determined in the selected-ion-monitoring (SIM) mode. The assay was validated in the range 0.3-1 ng/mg (depending on the drug) to 150 ng/mg, the mean absolute recoveries ranging from 66% to 110%, the matrix effect from 62% to 121% and process efficiency from 61% to 89% depending on the analyte. The intra- and inter-assay accuracy values were always better than 20%. The validated method was then successfully applied to real bone samples from forensic cases in which toxicological analysis for these drugs in blood was positive. Drugs were detected in bone in 12 of the 15 blood positive results. The approximate concentration range was 3-5 ng/g for 6-monoacetylmorphine, 3-7 ng/g for morphine, 14-28 ng/g for methadone and 6 ng/g and 11 ng/g for tramadol and benzoylecgonine.