Prolonged hypoglycemia after a suicidal ingestion of repaglinide with unexpected slow plasma elimination.

CONTEXT: Repaglinide is a short-acting insulin secretagogue with high interindividual variability in pharmacokinetics due to genetic polymorphisms. Little is known about repaglinide overdoses, both with respect to pharmacokinetics and appropriate management. Given its short serum half-life of less than 1 h, hypoglycemic effects of repaglinide are expected to cease within a few hours post-ingestion. CASE DETAILS: A 15-year-old girl ingested 10.5 mg of repaglinide in a suicide attempt. Few hours later, she developed a strong food craving, nausea, abdominal pain, and a headache. The lowest recorded serum glucose was 44 mg/dl (2.4 mmol/l) 14 h post-ingestion. Using liquid chromatography-mass spectrometry, we detected repaglinide serum levels of 5.3, 2.6, and 1.0 ng/ml at 14, 20, and 26 h post-ingestion, respectively. DISCUSSION: This case illustrates that in the context of overdose, repaglinide can lead to prolonged hypoglycemia. We therefore recommend glucose monitoring and observation for 24 h in all patients who remain hypoglycemic or show symptoms of hypoglycemia for an unusually long period of time.

Isoflurane but not sevoflurane or desflurane aggravates injury to neurons in vitro and in vivo via p75NTR-NF-ĸB activation.

BACKGROUND: General anesthesia in patients with or at risk for neuronal injury remains challenging due to the controversial influence of volatile anesthetics on neuronal damage. We hypothesized that isoflurane, sevoflurane, and desflurane would exert variable degrees of neurotoxicity in vitro and in vivo via activation of the p75 neurotrophin receptor (p75). METHODS: SH-SY5Y cells were exposed to oxygen-glucose deprivation (OGD, 16 hours), preceded or followed by incubation with isoflurane, sevoflurane, or desflurane (1.2 minimal alveolar concentration, 2 hours). Neuronal cell death was analyzed by flow cytometry (mitochondrial membrane potential, Annexin V/propidium iodide [AV/Pi]) and quantification of lactate dehydrogenase release. We analyzed NF-κB activity by DNA-binding ELISA and luciferase assay. The role of p75 was studied using the p75-blocking peptide TAT-pep5 and siRNA knockdown. The effect of isoflurane ±p75 inhibition on retinal ischemia-reperfusion injury (IRI) in adult Sprague-Dawley rats was assessed by analyzing retinal ganglion cell (RGC) density. RESULTS: Isoflurane but not sevoflurane or desflurane postexposure aggravated OGD-induced neuronal cell death (AV/Pi positive cells: OGD 41.1% [39.0/43.3] versus OGD + isoflurane 48.5% [46.4/63.4], P = 0.001). Isoflurane significantly increased NF-κB DNA-binding and transcriptional activity of NF-κB (relative Luminescence Units: OGD 500 [499/637] versus OGD + isoflurane 1478 [1363/1643], P = 0.001). Pharmacological inhibition or siRNA knockdown of p75 counteracted the aggravating effects of isoflurane. Isoflurane increased RGC damage in vivo (IRI 1479 RGC/mm(2) [1311/1697] versus IRI + isoflurane 1170 [1093/1211], P = 0.03), which was counteracted by p75-inhibition via TAT-pep5 (P = 0.02). CONCLUSIONS: Isoflurane but not sevoflurane or desflurane postexposure aggravates neurotoxicity in preinjured neurons via activation of p75 and NF-κB. These findings may have implications for the choice of volatile anesthetic being used in patients with or at risk for neuronal injury, specifically in patients with a stroke or history of stroke and in surgical procedures in which neuronal injury is likely to occur, such as cardiac surgery and neurovascular interventions.

Computer assisted modeling of ethyl sulfate pharmacokinetics.

For 12 volunteers of a drinking experiment the concentration-time-courses of ethyl sulfate (EtS) and ethanol were simulated and fitted to the experimental data. The concentration-time-courses were described with the same mathematical model as previously used for ethyl glucuronide (EtG). The kinetic model based on the following assumptions and simplifications: a velocity constant k(form) for the first order formation of ethyl sulfate from ethanol and an exponential elimination constant k(el). The mean values (and standard deviations) obtained for k(form) and k(el) were 0.00052 h(-1) (0.00014) and 0.561 h(-1) (0.131), respectively. Using the ranges of these parameters it is possible to calculate minimum and maximum serum concentrations of EtS based on stated ethanol doses and drinking times. The comparison of calculated and measured concentrations can prove the plausibility of alleged ethanol consumption and add evidence to the retrospective calculation of ethanol concentrations based on EtG concentrations.

Urine tested positive for ethyl glucuronide after trace amounts of ethanol.

AIM: Ethyl glucuronide (EtG) is used commonly as a marker for the detection of non-compliance of patients in alcohol withdrawal therapy in psychiatric hospitals in Europe and in work-place monitoring programmes in the United States. With the increased use of this new marker, questions related to an unintentional uptake of ethanol resulting in detectable EtG concentrations have been discussed. The aim of this study was to determine the concentration ranges of EtG and ethyl sulphate (EtS) after the consumption of very small amounts of ethanol (1 and 3 g), which are more likely to be incidental than intended. METHODS: Drinking experiments with ethanol amounts of 1 and 3 g, respectively, were performed on a total of 31 volunteers. EtG and EtS analysis in urine was performed by electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and creatinine concentration was determined using the Jaffé reaction. Furthermore, data obtained from this experimentation were then compared to data from literature. RESULTS AND CONCLUSIONS: The maximum concentration of EtG normalized to creatinine after the uptake of 1 g and 3 g of ethanol was found to be 0.32 mg/l and 1.53 mg/l, respectively, and 0.15 mg/l and 1.17 mg/l for EtS; these peak concentrations are considered to be positive by many laboratories testing urine for ethanol conjugates in work-place testing progammes.

Fatal and severe codeine intoxication in 3-year-old twins--interpretation of drug and metabolite concentrations.

This work presents two cases of codeine intoxication in 3-year-old monozygotic twin brothers while treated with a codeine slow-release formulation. One child had to be admitted to the hospital, whereas the other one died at home after aspiration of gastric content. The concentrations of codeine and major metabolites including morphine and corresponding glucuronide conjugates were measured by liquid chromatography-tandem mass spectrometry in serum, urine, cerebrospinal fluid, and brain tissue, respectively. A genetic polymorphism study was carried out in order to determine the ability of the children to metabolize codeine by O-demethylation. A pharmacokinetic calculation was also performed to estimate the administered dose of codeine in question. High concentrations of all substances were found in samples of both children. The pharmacokinetic estimate suggests an overdose of codeine, and the possible reasons for the high opiate concentrations are discussed. Furthermore, the postmortem distribution--during and after resuscitation--might play a major role in the interpretation of postmortem concentration levels.

Assessment of alcohol use among methadone maintenance patients by direct ethanol metabolites and self-reports.

BACKGROUND: Heavy alcohol consumption may accelerate the progression of hepatitis C (HCV)-related liver disease and/or limit efforts at antiviral treatment. As most of the patients in methadone maintenance treatment (MMT) suffer from hepatitis C infection, this study was conducted to identify the alcohol intake among these patients at a Swiss Psychiatric University Clinic by self-reports and direct ethanol metabolites as biomarkers of ethanol consumption. PATIENTS AND METHODS: A convenience sample of 40 MMT patients (15 women, 25 men; median age 39 years) of the total 124 patients was asked and consented to participate in this study. This sample was not different in age, gender distribution, and rate of hepatitis C infection from the total sample. The Alcohol Use Disorders Identification Test (AUDIT) and self-reported ethanol intake during the previous 7 days were assessed. In addition, ethyl glucuronide (EtG) in urine, and fatty acid ethyl esters (FAEEs) and EtG in hair were determined using LC-MS/MS and gas chromatograph/mass spectrometer. The limit of quantitation for UEtG, HEtG, and FAEEs were 0.1 mg/l, 2.3 pg/mg, and 0.1 ng/mg, respectively. RESULTS: Fourteen participants reported abstinence from alcohol for the previous 7 days. AUDIT scores were > or =8 in 15 male and >5 in 5 female participants. Direct ethanol metabolites were as follows (median, min, max, standard deviation): UEtG (19 positives; 9.91, 1.38 to 251, 62.39 mg/l); the values of HEtG were 17.65, 0 to 513, 105.62 pg/mg [in 2 cases no material, 8 abstinent (up to 7 pg/mg), 15 social drinkers (up to 50 g per day), and 15 excessive users (>50/60 g/d)]. For the 13 cases, where enough material for additional determination of HFAEEs was available, the values were 0.32, 0 to 1.32, 0.44 ng/mg. Among the 30 HEtG-positive participants, 20 had not reported the corresponding ethanol intake using question 1 (frequency) and 2 (quantity) of the AUDIT. Of the 14 participants reporting no alcohol intake during the previous 7 days, 4 were UEtG-positive. HEtG and AUDIT correlated significantly (r = 0.622, p < 0.0001), but this was not the case for UEtG and self-reported ethanol intake during the previous 7 days. CONCLUSION: (1) HEtG identified 20 cases of daily ethanol intake of more than 20 g, that would have been missed by the sole use of question 1 (frequency) and 2 (quantity) of the AUDIT. (2) Using the total score of the AUDIT, HEtG confirmed 10 more cases positive for alcohol intake. (3) Episodic heavy drinking is with 22.5% more frequent than in general population, and (4) of the 14 participants who reported no alcohol intake during the previous 7 days, 4 were UEtG positive. Improved detection of alcohol consumption, which is hazardous or harmful in the context of HCV and opiate dependence, would allow for earlier intervention in this population which is at particular risk of liver disease and fatal respiratory-depressed overdose. The combined use of self-reports and direct ethanol metabolites seems promising.

Sevoflurane-mediated activation of p38-mitogen-activated stresskinase is independent of apoptosis in Jurkat T-cells.

BACKGROUND: Modulation of the inflammatory stress response by anesthesia may be responsible for an increased susceptibility to infectious complications, such as wound infection or pneumonia. Sevoflurane, a specific inhibitor of activator protein-1, an immediate early transcription factor, induces apoptosis in T-cells. Because p38 can be involved either in pro- or antiapoptotic processes, we examined whether the sevoflurane-induced apoptosis is mediated by p38 activation in Jurkat T-cells. METHODS: Jurkat T-cells were exposed to different concentrations of sevoflurane, isoflurane, or desflurane in vitro. Phosphorylation of mitogen-activated protein (MAP) kinases, upstream kinases, downstream activating transcription factor 2 ATF-2, and caspase-3 processing were evaluated by Western blot. p38 kinase activity was evaluated after immunoprecipitation and phosphorylation of the substrate ATF-2 using Western blot. Apoptosis was assessed using flow cytometry after staining with green fluorescent protein-annexin V. RESULTS: While desflurane had no effect, sevoflurane and isoflurane induced p38 phosphorylation with sevoflurane inducing p38 kinase activity. Sevoflurane did not affect the MAP kinases ERK and JNK. Sevoflurane exposure also induced phosphorylation of apoptosis signal-regulating kinase-1 (ASK1), MAP kinase kinases 3 and 6 (MKK3/MKK6), and ATF-2. Pretreatment of cells with the general caspase inhibitor Z-VAD.fmk did not prevent the sevoflurane-induced phosphorylation of p38. Isoflurane- and sevoflurane-mediated caspase-3 processing and apoptosis could not be abolished by pretreatment with the specific p38 inhibitors SB202190 and SB203580. CONCLUSIONS: Sevoflurane is a specific activator of the apoptosis signal-regulating kinase-1-, MKK3/MKK6-p38 MAP kinase cascade in Jurkat T-cells. Our data suggest that sevoflurane-induced p38 activation is not affected by caspase activation. Furthermore, sevoflurane-induced apoptosis is not dependent on p38 MAP kinase activation.

Measurement of direct ethanol metabolites in a case of a former driving under the influence (DUI) of alcohol offender, now claiming abstinence.

A 37-year-old female subject had been convicted of driving under the influence of alcohol, and 19 months later, claimed abstinence after supervised disulfiram treatment. Our aim was to elucidate the value of direct ethanol metabolites as measures of abstinence. Ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) in hair, phosphatidylethanol in whole blood and EtG and ethyl sulphate in urine were measured. The results were compared with self-report of alcohol consumption and traditional blood biomarkers for chronically elevated alcohol consumption as carbohydrate deficient transferrin (CDT), gamma glutamyl transpeptidase, mean corpuscular erythrocyte volume, aspartate aminotransferase and alanine aminotransferase. EtG was found in distal parts of hair only, whereas the proximal parts were negative. Furthermore, FAEE concentrations were found in the typical distribution over the hair length and showed values typical for either moderate social drinking or abstinence. CDT was above cut-off in 9 out of 16 analyses with a decreasing tendency and the lowest values in the last 2 months before the end of sampling. The data suggest that in addition to traditional markers, a combination of direct ethanol metabolites can be useful in the expert assessment of judging driving ability. A careful individual interpretation of the results for the different markers, however, is an absolute necessity.

Kinetics in serum and urinary excretion of ethyl sulfate and ethyl glucuronide after medium dose ethanol intake.

The direct ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), are of increasing importance for clinical and forensic applications, but there are only few studies on the kinetics of EtG in serum and none on EtS. In this study, 13 volunteers (social drinkers) drank ethanol in the form of white wine to reach a blood alcohol concentration of 0.51 +/- 0.17 g/kg, and blood and urine samples were analyzed for EtG and EtS simultaneously by chromatography-tandem mass spectrometry (LC-MS/MS). Mean peak serum EtG and EtS concentrations were 2.9 +/- 1.3 and 2.8 +/- 1.6 micromol/l, respectively, and were reached between 4.0 +/- 0.9 h after the start of drinking (3.0 +/- 0.5 h for EtS). The mean time differences between reaching maximum blood ethanol levels and serum metabolite levels were 2.3 +/- 0.9 h for EtG and 1.2 +/- 0.5 h for EtS. In the last blood samples collected (10-11 h after the start of drinking), 11 (of 13) volunteers were still positive for EtG in serum, whereas only 2 were positive for EtS. In the serum of one female person, no EtS was detectable at any time; however, it was excreted in the urine in (low) concentrations. Ethanol was detectable in the serum for up to 8.6 h after the start of drinking, whereas EtG and EtS were detectable up to more than 5.8 h (EtG) and 4.0 h (EtS), respectively. Mean peak urinary concentrations were 401 +/- 232 micromol/l for EtG and 266 +/- 153 micromol/l for EtS, and mean peak levels were reached 6.2 +/- 0.9 h (EtG) and 5.3 +/- 1.2 h (EtS) after the start of drinking. Maximum concentrations of EtG and EtS in serum showed a wide interindividual variation and could not be correlated to the maximum blood ethanol concentrations. Correlations (p < 0.001, Kendall's Tau b) were found when comparing pairs of parameters, but mostly involved areas under the curve (AUC) of metabolites or of ethanol; one correlation linked the peak concentrations of EtG and EtS in urine.