Drugs in postmortem adipose tissues: evidence of antemortem deposition

INTRODUCTION: Drug concentration measured in postmortem adipose tissue may or may not reflect antemortem concentration. To examine the possibility of whether the presence of basic drugs in adipose tissue is the result of postmortem change, we examined: tissues with and without livor mortis, concentration gradients within the adipose layer, and the stability of drug concentrations during the postmortem period. CASE REPORTS: Five drug-related deaths with case histories and analytical data are presented. Adipose tissues with and without livor mortis from the thigh area of the same decedent were analyzed for cocaine. The cocaine concentration of the tissue exhibiting 4+ livor was equivalent to the concentration observed in tissue without livor. Analyses of cross sections of adipose tissues containing cocaine and methamphetamine disclosed that drug concentrations were equally distributed throughout the layer, from just beneath the dermis to directly above the muscle. When morphine and temazepam concentrations were measured in adipose tissues collected from similar sites, but at different times, from the same cadaver, they remained essentially the same over 3 days (approximately 80 h). CONCLUSIONS: Since concentrations were the same in areas with and without livor mortis, the possibility of redistribution into adipose from blood or vascular channels is eliminated. The absence of a concentration gradient within the adipose layer rules out diffusion or permeation from muscle into the adipose layer, and the failure of morphine or temazepam concentration to change over time indicates that drugs in the adipose tissue are stable during the postmortem interval. Our findings support the notion that drugs identified in postmortem adipose tissue are there because of antemortem deposition and not because of any postmortem change or event.     

Correlation of the incidence of cocaine and cocaethylene in hair and postmortem biologic samples

Hair samples are useful as a matrix for drug testing because drugs can be detected in hair for longer periods than in blood or urine. The authors report a prospective comparison of the detection of cocaine and cocaethylene in routine postmortem biologic specimens to the detection of cocaine and cocaethylene in hair. The authors collected hair samples from various areas of the head in 53 autopsy cases, prepared them, and analyzed them by gas chromatography/mass spectrometry (GC/MS) for cocaine and cocaethylene. The authors compared the results of hair analysis with the results of toxicologic analysis performed on routine postmortem samples by enzyme multiplied immunoassay technique and GC/MS. Cocaine was found in either biologic fluids or in hair in 16 of 53 samples tested. Nine samples were positive for cocaine in both biologic fluids and hair. Five samples contained cocaine only in biologic fluids, and two contained cocaine only in hair. Cocaethylene was present in two cases. Drug screening of hair provides additional information in some autopsy cases, but the authors have not made hair analysis a routine practice. It may prove useful to save hair samples in all cases for later analysis if warranted by additional history or autopsy findings.     

Serum beta-glucuronidase activity in polytrauma patients and in centrifuged autopsy blood samples]

The serum activity of beta-glucuronidase was investigated in 58 patients after severe trauma as well as in 43 autopsy cases. In 10 cases the enzyme activities in postmortem blood samples from the femoral vein were compared to those present in the correspondent heart blood samples. An elevated activity of beta-glucuronidase was observed in 14% of the patients within the first 36 h after severe trauma increasing to 62% in blood samples collected later on. The activity of beta-glucuronidase in the heart blood samples was always higher than in the corresponding sample from the femoral vein. In cases of prolonged post-mortem interval an elevated activity might have been due to bacterial contamination. In postmortal blood samples from the femoral vein an elevated enzyme activity was found in 70% of the study material. The results of the preliminary study on the activity of beta-glucuronidase in blood samples frequent in forensic routine work indicated that an elevated enzyme activity might be present for the following scenery: after severe trauma, in alcohol/drug abuse, presence of putridity/autolysis, presence of inflammatory processes, in diabetes as well as in carcinoma diseases. The significance of elevated beta-glucuronidase activity concerning alterations of unconjugated drug concentration due to in vitro cleavage of O-glucuronides should be investigated.     

An Examination of the Postmortem Redistribution of Fentanyl and Interlaboratory Variability,

Fentanyl is a synthetic opioid agonist used for pain control. Often administered as a transdermal patch, it is an interesting drug for study of postmortem redistribution. We hypothesized that fentanyl concentrations would increase over time after death, as measured in blood drawn on the day prior to autopsy and in blood drawn at the time of autopsy in ten cases where fentanyl patches were identified at the scene. Concentrations were compared, and heart blood to femoral blood ratios were calculated as markers of postmortem redistribution. Fentanyl concentrations measured in peripheral blood drawn the day of autopsy (peripheral blood 2 [PB2]) were higher than those drawn the day prior to autopsy (peripheral blood 1 [PB1]) with a mean ratio (PB2/PB1) of 1.80. The ratio of heart blood concentrations (HB) to femoral blood concentrations drawn at autopsy (PB2) had a mean ratio (HB/PB2) of 1.08. Some cases had blood from the same source analyzed at two different laboratories, and concentrations of fentanyl in those samples showed inter‐ and intralaboratory differences up to 25 ng/mL. Postmortem fentanyl concentrations may be affected by antemortem factors, postmortem redistribution, and laboratory variability. Forensic pathologists must use caution in interpreting fentanyl levels as part of death investigation.     

Morbus Fahr--considerations on a case of sudden death

This paper presents 21 cases related to cyanide intoxication by oral ingestion. Cyanide concentrations in biological specimens are especially different from the type of postmortem specimens, and very important in interpreting the cause of death in postmortem forensic toxicology. Besides the detection of cyanide in autopsy specimens, the autopsy findings were unremarkable. Biological samples (0.2mL or equal to less than 10μg of cyanide) were analyzed colorimetrically for cyanide. In a series of 21 cyanide fatalities, the concentration ranges (mean±SD) of cyanide in heart blood, peripheral blood and gastric contents were 0.1-248.6mg/L (38.1±56.6mg/L), 0.3-212.4mg/L (17.1±45.1mg/L) and 2.0-6398.0mg/kg (859.0±1486.2mg/kg), respectively. The ranges of the heart/peripheral blood concentration ratio and gastric contents/peripheral blood concentration ratio were 0.3-10.6 (mean 3.4) and 3.4-402.4 (mean 86.0), respectively. From the difference of cyanide concentration and the concentration ratio of cyanide in different types of postmortem specimens, the possibility of the postmortem redistribution of cyanide and death by oral ingestion of cyanide could be confirmed. We reported cyanide fatal cases along with a review of literature.     

氯氮平在家兔体内死后再分布规律研究

目的阐明死后48h内家兔体内氯氮平再分布规律,为相关法医鉴定工作提供借鉴。方法取家兔15只,随机分为5组,以氯氮平灌胃,分别于死后0、6、12、24、48h取心血、外周静脉血、尿液、肝组织检测氯氮平浓度。结果家兔死亡后心血、外周静脉血、肝脏氯氮平浓度不断升高,尿液氯氮平浓度不断降低;死后早期浓度变化率大于晚期浓度变化率。死后48h心血、外周静脉血、肝脏、尿液氯氮平浓度分别为死后0h各检材氯氮平浓度的418%、193%、154%和29%。结论死亡一段时间后,提取生物检材,检测出的氯氮平浓度并不能准确反映刚死时的实际浓度。     

Fatal mephenesin intoxication

This report describes a death related to the abuse of and intoxication by mephenesin. To the best of our knowledge, this is the first report case of lethal intoxication involving solely mephenesin and reporting mephenesin blood concentrations. The victim was a 48-year-old woman found unconscious at home. Resuscitation was unsuccessful. Toxicological analysis was performed on a blood sample collected during resuscitation. The results being negative, the body was exhumed for an autopsy, which revealed bronchial inhalation syndrome. Analysis in a second laboratory has revealed the presence of mephenesin in samples collected during autopsy. No other drug/toxin was found, and alcohol was negative. Reanalysis of the peripheral blood collected during resuscitation found a mephenesin concentration of 15.81 microg/mL (15-fold greater that the maximum concentration that would result from a single intake of a 500 mg formulation). The pathologist has concluded on a bronchial inhalation syndrome consecutive to a mephenesin overdose as the cause of death. The manner of this death is discussed in the light of the toxicological hair analysis and the medical past of the victim.     

Polydrug fatality involving metaxalone

A 29-year old female with a history of depression was found dead in a hotel room. The death scene investigation found empty pill bottles and an empty liter bottle of wine. Metaxalone, a centrally acting muscle relaxant, along with citalopram, ethanol, and chlorpheniramine were identified in the postmortem samples and quantitated by gas chromatography-mass spectrometry. The concentration of metaxalone in femoral vein blood was 39 mg/L. The heart blood concentration was 54 mg/L. Femoral vein blood concentrations of citalopram and chlorpheniramine were 0.77 mg/L and 0.04 mg/L, respectively. Ethanol levels were 0.13 g/dL in vitreous and 0.08 g/dL in heart blood. Other tissue samples were also analyzed. The authors consider the metaxalone concentrations toxic and potentially fatal. The citalopram concentrations were lower than those reported in fatal cases for this drug alone. Death was ascribed to polydrug abuse/overdose with metaxalone a major contributor. This represents the first reported case to our knowledge in which a metaxalone overdose significantly contributed to death.     

Methanol Detected in a Subdural Hematoma as an Embalming Artifact

Analysis of subdural hematomata has been used to suggest antemortem drug concentrations, with the assumption that materials within the hematoma are less subject to metabolism or degradation during any survival period and postmortem interval. We report the case of an 87‐year‐old woman whose death had not been reported to the coroner's office until postembalming. Autopsy revealed a traumatic brain injury with subdural hematoma causing a mass effect. Testing of the clot indicated a methanol concentration of 51.8 mg%. No additional analyses were detected. These findings suggest that methanol can be present in a postmortem hematoma sample, yet not represent a poisoning. Our findings also suggest that while the interior of hematomata do not necessarily represent completely “protected space” from postmortem diffusion of some blood constituents, such diffusion is not facile, and analysis may still provide useful indications of antemortem drugs present, if not actual concentrations.     

Vitreous Humor: Biochemical Constituents in Estimation of Postmortem Interval*,†

Abstract: Analysis of biochemical constituents of the vitreous humor can be useful in determining the postmortem interval as there is proportionate postmortem rise of potassium and fall in sodium concentration. We studied 120 autopsy cases to determine the utility of potassium, sodium, calcium, and chloride levels, and sodium/potassium ratio in estimating the postmortem interval. There was a linear relationship between vitreous potassium concentration and postmortem interval, whereas an inverse relationship between vitreous sodium/potassium ratio and postmortem interval was noted. Other factors like age, sex, cause of death, season of death, and refrigeration of sample did not influence the vitreous humor potassium values. Using the statistical tools, a new formula was derived to determine the postmortem interval based on the potassium concentration and a review of previous literature is presented. Hence, the findings of this study supported a central role of vitreous humor biochemistry in many postmortem forensic and pathological evaluations.     

Postmortem diagnosis of sepsis

Human sepsis is a spectrum of pathophysiological changes in the host system resulting from a generalized activation and systemic expression of the host's inflammatory pathways in response to infection. Since autopsy findings and routine histology in cases of suspected fatal sepsis are most often unspecific and unconvincing, a number of studies has recently dealt with different methods and markers to better define criteria for the postmortem diagnosis of sepsis. Research carried out on specimens obtained postmortem from sepsis-associated fatalities is an important tool to improve our understanding of inflammatory organ changes and the associated underlying pathophysiological mechanisms. One pitfall the investigator has to be aware of is how to select appropriate case material that constitutes the basis for the setting-up of reference values that derive from such studies. Since no scientific studies have investigated the value of cardiac blood samples in the present context, autopsy blood samples for the determination of biochemical sepsis markers have to derive from the femoral vein. In both sepsis cases as well as controls, the time of death has to be well defined.     

Amphetamines in washed hair of demonstrated users and workplace subjects

Cardiovascular complications of cocaine abuse include myocardial ischemia and infarction, dysrhythmias, cardiomyopathies and aortic dissection. The case in point pertains to a 26-year-old, Caucasian male, substance abuser who suffered a thoracic aortic dissection following the use of crack cocaine. The autopsy and histological findings showed a connective tissue abnormality including a focal microcystic medial necrosis and a fragmentation of the elastic fibers in the arterial walls. Blood concentrations of cocaine and benzoylecgonine, taken individually, were considered to be within a potentially toxic range. Blood concentrations of methadone also indicated use of this drug at the same time. The small amounts of morphine found in the blood and urine were compatible with heroine or morphine use more than 24 h before death.     

The forensic science implications of site and temporal influences on postmortem blood-drug concentrations

The dependence of postmortem blood-drug concentrations on the collection site and on the postmortem interval before specimen collection has been studied. These studies consisted of both sequential sampling from the same collection site at defined time intervals and a comparison of the drug concentrations of postmortem blood simultaneously collected from various sites. A site and time dependence was observed for postmortem blood-drug concentrations. The heart blood-drug concentrations were, in general, significantly higher than those of peripheral specimens. As a result of this phenomenon, the analysis of peripheral blood specimens and solid tissues is often necessary before a definitive interpretation of postmortem toxicological analyses is possible.     

Brain concentrations of cocaine and benzoylecgonine in fatal cases

Since cocaine in blood rapidly hydrolyzes to benzoylecgonine, cocaine concentrations determined in postmortem blood may not reflect the presence or concentration of cocaine in the body at the time of death. The interpretative value of the determination of cocaine and benzoylecgonine in brain tissue was investigated. Cocaine and benzoylecgonine were quantitated by coextraction and formation of the propyl derivative of benzoylecgonine followed by selected ion monitoring gas chromatography/mass spectrometry (GC/MS) using electron ion impact ionization. Cocaine and benzoylecgonine were found to be evenly distributed throughout the brain. Cocaine and benzoylecgonine concentrations were stable in frozen brain tissue (-4 degrees C) on reanalysis after 1 to 3 months of storage, and in refrigerated tissue (10 degrees C) after 30 days of storage. Blood, brain, and liver concentrations of cocaine and benzoylecgonine in 37 cocaine overdose cases and 46 cases in which cocaine was incidental to the cause of death were reviewed. The ratios of cocaine/benzoylecgonine in the toxic cases (brain mean 14.7 and blood mean 0.64) were clearly different from those found in the incidental cases (brain mean 0.87 and blood mean 0.27). The brain/blood ratios of cocaine and benzoylecgonine concentrations generally were characteristic of the time elapsed since cocaine dosing. In cocaine overdose cases, the mean ratio was 9.6 for cocaine and 0.36 for benzoylecgonine. These are within the range found in animal studies for brain/blood ratios of cocaine and benzoylecgonine 0.5 to 2 h after cocaine administration. In incidental cases, the brain/blood ratios were mean 2.5 for cocaine and 1.4 for benzoylecgonine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fatal methanol intoxication with different survival times--morphological findings and postmortem methanol distribution

Three corresponding cases of fatal methanol intoxication with different survival times were investigated ante-mortem and postmortem. Ante-mortem serum methanol concentrations were determined during treatment in hospital for 4 days. Furthermore, postmortem distribution of methanol in various tissues and fluids was measured after autopsy. Morphological and toxicological findings are discussed based on the literature. The morphological findings correlated with the different survival times. The results of the toxicological analyses were partly in keeping with previously published data. Interestingly, very high methanol levels were determined in brain with very low concentrations in femoral venous blood. These results may have implications for postmortem toxicological analysis, brain death diagnosis and organ explanation for transplantation.     

Postmortem stability and interpretation of beta 2-agonist concentrations.

This paper describes a series of stability and redistribution studies aimed at understanding the presence and significance of beta 2-agonists in asthma deaths. Salbutamol and terbutaline were shown to be stable in postmortem blood at 23 degrees C for 1 week, 4 degrees C for 6 months and -20 degrees C for 1 to 2 years. However, fenoterol was shown to degrade at 23 degrees C (83% loss), 4 degrees C (93% loss) and -20 degrees C (66% loss) over the same time. Salbutamol concentrations detected in blood taken at the time of body admission to the mortuary were not significantly different from the concentrations detected in blood taken from the same cases at the time of autopsy (45 h later). This suggests that significant postmortem redistribution of salbutamol is unlikely to occur during this period. Postmortem blood concentrations of at least salbutamol are likely to reflect the concentration of these drugs in the body at the time of death.     

Concentrations of Opiates and Psychotropic Agents in Polydrug Overdoses: A Surprising Correlation Between Morphine and Antidepressants

Abstract: The relationship between postmortem concentrations of morphine and co‐detected psychoactive drugs in fatal overdoses is examined. Morphine and other drugs were detected in 161 medicolegal autopsy cases. Subsets of these morphine‐positive cases based on drug class were established, including opioids, antidepressants, ethanol, benzodiazepines, and “other.” Each subset was split into high or low concentration groups based on median drug concentrations. Morphine concentrations of the [high] and [low] groups were compared, with no significant difference in morphine concentration identified in the opioid, ethanol, or benzodiazepine subsets. The “other” drug class was too heterogeneous for statistical assessment. Morphine concentrations did show a significant direct relationship (p = 0.01) with antidepressants, namely increased concentrations of antidepressant drugs are associated with an increased concentration of morphine. This trend probably remains even after excluding cocaine‐positive cases. The unsuspected finding that postmortem concentrations of antidepressants positively correlate with morphine levels may be important in the treatment of depression in drug addicts.     

Postmortem diagnosis of meningococcemia by detection of capsular polysaccharides

Detection of specific meningococcal capsular polysaccharide (CPS) in postmortem blood permits rapid diagnosis of meningococcemia and differentiation from pneumococcemia and septicemia caused by Haemophilus influenzae Type b. We present studies validating application of latex agglutination assay for CPS on blood samples collected at autopsy, delineate the circumstances when CPS testing is indicated, and illustrate the usefulness of this procedure by several recent cases. Blood samples from victims dying of injury or disease other than infection were examined to determine whether the postmortem interval, bacterial contamination, anticoagulants, or delay in testing would result in false positive assays. Series 1 samples, collected so as to minimize bacterial contamination, were immediately submitted for assay. Series 2 evaluated the effect of adverse conditions of collection, anticoagulation, and prolonged sample storage. Despite extended postmortem intervals of up to 14 days, heavy bacterial contamination, prolonged storage at 4 degrees C, deep hemolysis, and presence of anticoagulants, false positive assays were seldom observed.     

The extent of postmortem drug redistribution in a rat model.

The aim of this study was to investigate the postmortem redistribution of several drugs in a rat model and to examine if any of the pharmacological properties was related to the extent of this phenomenon. One of the following drugs: phenobarbital (phenobarbitone), acetaminophen (paracetamol), carbamazepine, codeine, verapamil, amphetamine, mianserin, trimeprazine (alimemazine) or chloroquine was administered together with nortriptyline orally to rats 90 min prior to sacrifice. Heart blood was sampled immediately before sacrifice and after 2 h postmortem, as it has previously been shown that this is sufficient time for postmortem concentration changes to occur in heart blood. Blood was also sampled from the clamped abdominal inferior vena cava (representing peripheral blood) and tissue samples were taken from lungs, myocardium, liver, kidney, thigh muscle, forebrain, and vitreous humor together with a specimen from the minced carcass. Drugs were analyzed by high performance liquid or gas chromatography. For phenobarbital, acetaminophen and carbamazepine the postmortem to antemortem blood drug concentration ratios were close to 1.0 and tissue concentrations were low. The postmortem to antemortem heart blood drug concentration ratio for chloroquine (6.9 +/- 1.5) was higher than for nortriptyline (3.5 +/- 0.3), and the remaining drugs (codeine, verapamil, amphetamine, mianserin, and trimeprazine) showed ratios of the same magnitude as nortriptyline. The postmortem to antemortem blood drug concentration ratios for both heart blood and blood from the vena cava and also the lung to antemortem blood drug concentration ratio were closely related to the apparent volume of distribution for the drugs studied (p < 0.001). Accordingly, an apparent volume of distribution of more than 3-4 L/kg is a good predictor that a drug is liable to undergo postmortem redistribution with significant increments in blood levels. The postmortem drug concentration in blood from vena cava was closely related to the antemortem blood level, confirming that among the postmortem samples, the peripheral blood sample was the most representative for the antemortem blood concentration.