Postmortem Serum Samples Research Articles

Paraquat Poisoning: Insights from Autopsy, Histology, and Liquid Chromatography with Tandem Mass Spectrometry in Multidisciplinary Forensic Toxicology Practice.

The herbicide paraquat (PQ) is responsible for a significant number of fatalities resulting from self-poisoning. Nevertheless, only a limited number of comprehensive studies focusing on fatal PQ poisoning, which include examination of autopsy findings, histopathology, and quantitative analysis of post-mortem samples, have been published. This study aimed to evaluate autopsy findings, histopathology, and quantitative analysis of PQ in post-mortem human serum samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a simple, sensitive, and specific method. Autopsies were performed on all deaths due to PQ poisoning, and serum samples were sent to the toxicology laboratory for chemical analysis. The method was successfully applied to seven human serum samples, and the results indicate its reliability for detecting PQ. The study reports fatal serum PQ levels ranging from 0.5 to 372.0 µg/mL. The comprehensive data presented in this study can be useful for further research and practical applications.

Abstract TP238: Blood Brain Barrier Injury Detected in the Serum of Patients With a History of Stroke and Transient Ischemic Attack

Introduction: Stroke and transient ischemic attack (TIA) increase risk for cognitive impairment and dementia. Without a lasting infarction, the cause of cognitive decline after TIA remains unknown. We hypothesize that these cerebrovascular accidents (CVAs) have long-term negative effects on the blood brain barrier (BBB) and promote endothelial inflammation, both of which are associated with neurodegeneration. We sought to investigate the effects of CVAs on BBB integrity and endothelial inflammation by evaluating PDGFRβ and VCAM-1 serum levels, respectively. Methods: A subset of 88 subjects in the Arizona Study of Aging and Neurodegenerative Disorders with postmortem serum samples were available for analysis. Sandwich ELISA was performed to detect PDGFRβ and VCAM-1. Statistical analyses were performed using Spearman’s rank correlation and Mann Whitney U test. Results: Our subjects were split based on CVA status and matched according to vascular risk factors. Both subjects with stroke and subjects with TIA had increased serum PDGFRβ compared to those without history of CVA (6608.4 pg/mL and 5337.0 pg/mL, P=0.04, and 7849.5 pg/mL vs. 5337.0 pg/mL, P<0.01). No significant differences related to PDGFRβ were observed between subjects with stroke vs. TIA (P=0.25). PDGFRβ was associated with VCAM-1 (Spearman’s r=0.44, P<0.01) and VCAM-1 trends towards being higher in subjects with CVA compared to those without (P=0.13). Conclusions: PDGFRβ was elevated in subjects who had a history of stroke or TIA compared to matched patients without CVA. These data demonstrate the utility of a serum-based biomarker of BBB integrity, a powerful tool in studying the role of the BBB in various neurodegenerative diseases including Alzheimer’s dementia. These data also raise the possibility that TIA and stroke have lasting effects on BBB integrity and provide insight about their mechanistic role in neurodegeneration. These findings are limited by our small sample size and post-mortem serum collection; still more, these promising serum biomarkers need further validation.

Minimally Invasive Tissue Sampling: A Tool to Guide Efforts to Reduce AIDS-Related Mortality in Resource-Limited Settings.

BackgroundAvailable information on the causes of death among people living with human immunodeficiency virus (PLHIV) in low- and middle-income countries (LMICs) remains scarce. We aimed to provide data on causes of death in PLHIV from two LMICs, Brazil and Mozambique, to assess the impact of clinical misdiagnosis on mortality rates and to evaluate the accuracy of minimally invasive tissue sampling (MITS) in determining the cause of death in PLHIV.MethodsWe performed coupled MITS and complete autopsy on 164 deceased PLHIV (18 children, 36 maternal deaths, and 110 adults). HIV antibody levels and HIV RNA viral loads were determined from postmortem serum samples.ResultsTuberculosis (22.7%), toxoplasmosis (13.9%), bacterial infections (13.9%), and cryptococcosis (10.9%) were the leading causes of death in adults. In maternal deaths, tuberculosis (13.9%), bacterial infections (13.9%), cryptococcosis (11.1%), and cerebral malaria (8.3%) were the most frequent infections, whereas viral infections, particularly cytomegalovirus (38.9%), bacterial infections (27.8%), pneumocystosis (11.1%), and HIV-associated malignant neoplasms (11.1%) were the leading cause among children. Agreement between the MITS and the complete autopsy was 100% in children, 91% in adults, and 78% in maternal deaths. The MITS correctly identified the microorganism causing death in 89% of cases.ConclusionsPostmortem studies provide highly granular data on the causes of death in PLHIV. The inaccuracy of clinical diagnosis may play a significant role in the high mortality rates observed among PLHIV in LMICs. MITS might be helpful in monitoring the causes of death in PLHIV and in highlighting the gaps in the management of the infections.

Application of a UHPLC-MS/MS method to investigate the metabolic pathways of Alzheimer’s disease and dementia with Lewy bodies using postmortem cerebrospinal fluid and serum samples

Application of a UHPLC-MS/MS method to investigate the metabolic pathways of Alzheimer’s disease and dementia with Lewy bodies using postmortem cerebrospinal fluid and serum samples

A synergy of liquid chromatography with high-resolution mass spectrometry and coagulation test for determination of direct oral anticoagulants for clinical and toxicological purposes.

Direct oral anticoagulants are an alternative to anticoagulants based on vitamin K antagonists. Monitoring of direct oral anticoagulant concentration levels is necessary in specific cases (e.g. in emergency conditions, for determination of the cause of bleeding, adverse effects, risk of drug-direct oral anticoagulants interaction); therefore, a sensitive and specific method is needed. A methanol protein precipitation method followed by liquid chromatography with high-resolution mass spectrometry was developed for simultaneous separation and determination of apixaban, betrixaban, edoxaban, dabigatran, rivaroxaban and ximelagatran. The proposed method was fully validated in terms of linearity, the limits of detection and quantification, intra- and inter-day trueness and precision, recovery, matrix effect, process efficiency and stability. The method shows a strong correlation (Pearson's correlation coefficients > 0.92) with coagulation assays of apixaban, dabigatran and rivaroxaban (dilute thrombin time for gatrans and anti Xa factor (anti-Xa) activity for xabans). In addition, the developed method was applied for the identification and determination of apixaban and dabigatran in post-mortem serum samples. The developed method is a good alternative to coagulation tests which may show various interferences.

Development and validation of a method for quantification of human insulin and its synthetic analogues in plasma and post-mortem sera by LC-MS/HRMS

Analysis of human insulin and its synthetic analogues is increasingly requested for clinical monitoring, for anti-doping purposes, but also for forensic cases. Indeed, insulin analogues may be abused for suicide or homicide – whence their forensic interest. Collection and storage conditions, as well as the phenomenon of degradation make post-mortem serum samples analytically challenging and consequently, the rate of exogenous insulin administration as cause of death is undoubtedly underestimated. However, with recent technological advances and the development of new extraction techniques particularly for anti-doping analyses, detection of insulins in post-mortem samples seems to be achievable. This study describes the first validated quantitative method for analysis human insulin and its six analogues (lispro, aspart, glulisine, glargine, detemir and degludec) in plasma and post-mortem sera. Various extraction processes, namely precipitation + solid phase extraction (SPE), filtration + SPE, precipitation + SPE + immunopurification, and filtration + immunopurification, were assessed to evaluate the lowest limit of detection for all target analogues. The selected sample preparation consists of filtration step followed by immunopurification extraction with an anti-body precoated ELISA plate for plasma. For post-mortem sera, the first step of precipitation was added to remove matrix interferences. The extracts were analyzed by ultra-high-performance liquid chromatography-high resolution mass spectrometry (LC-HRMS), interfaced by electrospray (ESI). The method was validated with respect linearity, precision, accuracy, recovery, matrix effect, dilution and carryover. The limit of quantification (LOQ) in plasma was 0.5 ng/mL for human insulin and rapid-acting insulins, 1.0 ng/mL for glargine, 2.5 ng/mL for degludec and 10 ng/mL for detemir. Two types of post-mortem sera were studied based on the post-mortem interval (PMI): inferior or superior to 48 h. The obtained LOQ were the same for each analogue, independent from the PMI: 1.0 ng/mL for human insulin and rapid-acting insulins, 1.0 ng/mL for glargine, 2.5 ng/mL for degludec and 10 ng/mL for detemir. At the LOQ level, for all insulins and all samples, accuracy was between 70 and 130% and precision inferior to 30%. The validated method was applied to five subjects participating in therapeutic monitoring of insulin and to seven post-mortem cases.

Partial MHC/neuroantigen peptide constructs attenuate methamphetamine-seeking and brain chemokine (C–C motif) ligand 2 levels in rats

There are no medications that target the neurotoxic effects or reduce the use of methamphetamine. Recombinant T-cell receptor ligand (RTL) 1000 [a partial major histocompatibility complex (pMHC) class II construct with a tethered myelin peptide], addresses the neuroimmune effects of methamphetamine addiction by competitively inhibiting the disease-promoting activity of macrophage migration inhibitory factor to CD74, a key pathway involved in several chronic inflammatory conditions, including substance use disorders. We previously reported that RTL constructs improve learning and memory impairments and central nervous system (CNS) inflammation induced by methamphetamine in mouse models. The present study in Lewis rats evaluated the effects of RTL1000 on maintenance of self-administration and cue-induced reinstatement using operant behavioral methods. Post-mortem brain and serum samples were evaluated for the levels of inflammatory factors. Rats treated with RTL1000 displayed significantly fewer presses on the active lever as compared to rats treated with vehicle during the initial extinction session, indicating more rapid extinction in the presence of RTL1000. Immunoblotting of rat brain sections revealed reduced levels of the pro-inflammatory chemokine (C–C motif) ligand 2 (CCL2) in the frontal cortex of rats treated with RTL1000, as compared to vehicle. Post hoc analysis identified a positive association between the levels of CCL2 detected in the frontal cortex and the number of lever presses during the first extinction session. Taken together, results suggest that RTL1000 may block downstream inflammatory effects of methamphetamine exposure and facilitate reduced drug seeking—potentially offering a new strategy for the treatment of methamphetamine-induced CNS injury and neuropsychiatric impairments.

Loss of Ca2+/Calmodulin Dependent Protein Kinase Kinase 2 Leads to Aberrant Transferrin Phosphorylation and Trafficking: A Potential Biomarker for Alzheimer's Disease.

Ca2+/calmodulin-dependent protein kinase kinase 2 (CaMKK2) is a serine/threonine kinase that is activated following an increase in the intracellular Ca2+ concentration and activates multiple signaling cascades that control physiologically important neuronal processes. CaMKK2 has been implicated in schizophrenia, bipolar disease, neurodegeneration, and cancer. Using isoelectric focusing (IEF) and mass spectrometry-based proteomic analysis, it was found that knockdown (KD) of CaMKK2 in cultured adult primary dorsal root ganglion (DRG) neurons resulted in the reduction of transferrin (TF) phosphorylation at multiple functionally relevant residues which corresponded to loss of an acidic fraction (pH~3-4) of TF. In vitro studies using CRISPR/Cas9 based CaMKK2 knockout (KO) HEK293 and HepG2 cells lines validated previous findings and revealed that loss of CaMKK2 interfered with TF trafficking and turnover. TF is an iron transporter glycoprotein. Abnormal accumulation of iron and/or deregulated Ca2+ homeostasis leads to neurodegeneration in Alzheimer's disease (AD). Therefore, it was hypothesized that aberrant CaMKK2 in AD may lead to aberrant phosphorylated transferrin (P-TF: pH~3-4 fraction) which may serve as a hallmark biomarker for AD. A significant reduction of P-TF in the brain and serum of CaMKK2 KO mice and a triple-transgenic mouse model of AD (3xTg-AD) supported this hypothesis. In addition, analysis of early (< 65 years) and late-stage (>65 years) postmortem human AD cerebrospinal fluid (CSF) and serum samples revealed that aberrant P-TF (pH~3-4 fraction) profile was associated with both early and late-stage AD compared to age-matched controls. This indicates P-TF (pH~3-4 fraction) profile may be useful as a minimally invasive biomarker for AD. In addition, this study provides a link between aberrant CaMKK2 with TF trafficking and turnover which provides a novel insight into the neurodegeneration process.

Usefulness of liver function tests in postmortem samples

Liver function tests have been investigated in the forensic setting in several biological fluids collected at autopsy. Nevertheless, the results of these investigations have provided diverging information on postmortem stability of liver function markers and postmortem reliability of liver function assessment. The first aim of this study was to determine gamma-glutamyltransferase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, total proteins, and albumin in antemortem and postmortem serum samples in a series of cases that underwent forensic investigations and had both samples available. The second aim was to measure total bilirubin and gamma-glutamyltransferase in cerebrospinal fluid. Preliminary results indicated that femoral (and cardiac) blood postmortem serum concentrations of bilirubin, total proteins, and albumin, as well as femoral blood postmortem serum concentrations of gamma-glutamyltransferase, can be considered to reliably reflect antemortem serum concentrations, thus suggesting that postmortem values could be used as surrogates for antemortem levels. Measurable bilirubin levels were demonstrable in cerebrospinal fluid samples in both preservative-free and sodium fluoride tubes, though with levels varying widely and unpredictably, irrespective of liver disease severity.

Cardiac troponins and NT-proBNP in the forensic setting: Overview of sampling site, postmortem interval, cardiopulmonary resuscitation, and review of the literature

The possible use of biochemical markers in the postmortem diagnosis of myocardial ischemia is well known in the forensic setting, though several issues have limited its widespread adoption. The study presented herein focuses of N-terminal pro-B-type natriuretic peptide, troponin T, and troponin I, and the possible influence due to sampling site chosen, postmortem interval elapsed, and cardiopulmonary resuscitation attempts. Comparisons were performed between antemortem serum levels of these markers and postmortem levels measured in pericardial fluid and postmortem serum samples obtained from different sampling sites (n=16). Levels of these markers were also compared in cases characterized by various postmortem intervals (n=48, consisting of 24 ischemic heart disease cases and 24 controls) as well as in cases with and without cardiopulmonary resuscitation (n=22, consisting of 14 cases of hanging and 8 cases of drug intoxication). Our results indicate that N-terminal pro-B-type natriuretic peptide, troponin T, and troponin I values determined in postmortem serum from femoral blood (collected up to 24h after death) do not differ significantly from those measured in venous blood antemortem serum samples (collected at the upper limbs). In addition, our results reveal that the time elapsed after death should always be taken into consideration when cardiac troponins are measured in postmortem samples. Lastly, our findings reveal the absence of statistically significant differences between levels of the tested biomarkers (in postmortem serum from femoral blood) in cases without cardiopulmonary resuscitation compared to cases with cardiopulmonary resuscitation (at least for postmortem intervals up to 24h).

Postmortem evaluation of cholesterol, triglyceride, and apolipoprotein levels.

Cholesterol and triglyceride levels have been analyzed in the forensic setting and their values correlated with atherosclerotic lesions found at autopsy and histology. Nevertheless, the results of these investigations have provided diverging information on postmortem molecule stability and postmortem measurement reliability. The aim of this study was to determine triglycerides, total cholesterol, low-density and high-density lipoprotein cholesterol, apolipoprotein B100, and apolipoprotein A-I in antemortem and postmortem serum samples in a series of cases (N=10, including cardiac and noncardiac deaths) that underwent forensic investigations and had both samples available, measure the same molecules in postmortem serum from femoral blood and pericardial and pleural fluids (N=39, including cardiac and noncardiac deaths), and evaluate whether different levels of these molecules could be observed in cases characterized by different degrees of coronary artery atherosclerosis (N=39, including cardiac and noncardiac deaths). Preliminary results indicated that total cholesterol and low-density and high-density lipoprotein cholesterol levels in postmortem serum samples tended to be lower than those in antemortem specimens, whereas triglyceride levels in postmortem serum samples tended to be higher than those in antemortem samples. No relationship could be found between postmortem serum and pericardial fluid levels or between postmortem serum and pleural fluid levels of all tested biomarkers. Lastly, cases characterized by severe coronary artery atherosclerosis revealed higher postmortem serum levels of total cholesterol and apolipoprotein B. Globally considered, these data confirm that femoral blood postmortem serum levels of cholesterol and apolipoproteins may be considered suitable to estimate their antemortem values in forensic cases characterized by coronary artery atherosclerosis.

Endocan concentrations in postmortem serum, vitreous humor and urine in victims of lethal hypothermia

Endocan is a soluble molecule secreted from vascular endothelial cells of various organs. Its exact function in humans remains to be elucidated, though it has been postulated that increased tissue expression or serum levels of this molecule may be an indicator of endothelial activation and neovascularization. In the realm of forensic pathology, studies pertaining to endothelial activation following exposure to cold exclusively focused on thrombomodulin, a transmembrane protein specific to endothelial cells. In the study herein described, endocan concentrations were determined in postmortem serum, urine and vitreous humor samples collected during autopsy in a series of cases that underwent medicolegal investigations. A total of 76 autopsy cases were selected and three study groups (hypothermia group, sepsis group and non-hypothermia/non-sepsis group) prospectively formed during the study period. The obtained results seem to indicate that exposure to cold and subsequent death is not distinguished by significant endothelial dysfunction causing enhanced endocan secretion.

Postmortem serum levels of total IgE.

The first aim of this study was to assess whether non-allergic deaths in non-atopic individuals with increasing postmortem intervals are characterized by progressively greater concentrations of total IgE in postmortem serum from femoral blood. Our second goal was to determine whether traumatic deaths with different survival times, septic deaths, and deaths in individuals suffering from diseases with significant systemic inflammation are systematically characterized by increased concentrations of total IgE in postmortem serum from femoral blood. Four study groups were prospectively and retrospectively formed (non-allergic deaths in non-atopic individuals with increasing postmortem intervals, traumatic deaths in non-atopic individuals with different survival times, deaths possibly related to sepsis in non-atopic individuals, and deaths occurring in non-atopic individuals with disseminated malignancies at autopsy). Unenhanced computed tomography, autopsy, histology, and biochemistry were performed in all cases. First results indicate that increasing postmortem intervals are not associated with progressively increasing postmortem serum IgE levels. Moreover, the obtained results do not reveal that severe trauma, bacterial sepsis, and disseminated malignancies are systematically associated with increased postmortem serum IgE levels, irrespective of survival time duration. Though the usefulness of increased total IgE concentrations in postmortem samples to assess any underlying atopic disposition or death preceded by acute IgE-mediated allergic reaction remains questionable, measurements of total IgE are possible in postmortem serum samples.

Postmortem serum tryptase levels in anaphylactic and non-anaphylactic deaths

BackgroundThe postmortem diagnosis of anaphylaxis remains difficult due to the lack of specific biomarkers. Mast cell tryptase (MCT) levels are used as a marker of mast cell degranulation in living...

Postmortem serum tenascin-C (TN-C) concentrations in forensic autopsy cases: A pilot study

In forensic investigations, autopsy findings offer major clues for the diagnosis of the cause of death. Thus, various clinical biochemical markers are now being tested to complement conventional investigation in the field of forensic medicine. In this study, we focused on tenascin-C (TN-C), a glycoprotein present in the extracellular matrix and expressed in pathological states. We reviewed autopsy cases for a 4-year period (2006-2009) using autopsy records, and analyzed the blood serum concentrations of TN-C and C-reactive protein (CRP) in these cases (N=101). The TN-C levels were relatively higher in the postmortem serum samples than in the samples from healthy individuals, and in cases of head injury, both TN-C and CRP levels were high in the postmortem serum sample. Moreover, high TN-C levels were observed particularly in cases with a long survival period. These findings indicate that postmortem serum TN-C levels may represent a useful tool for identifying the cause of specific fatal traumas.

Validation of Virus NAT for HIV, HCV, HBV and HAV Using Post-Mortal Blood Samples

Objective: Commercial available NAT systems are usually not validated for screening of post-mortem blood samples. NAT testing might be challenging due to inhibitory substances in the cadaveric blood sample that cause false-negative test results. Validation studies have to be performed to show the performance characteristics of the NAT assays for testing cadaveric blood. Methods: A set of 32 post-mortem serum and plasma samples from cornea donors and 40 control samples from blood donors, serologically and NAT negative for all investigated parameters, were spiked with defined concentrations of WHO reference material and tested for HIV-1, HCV, HBV, and HAV by NAT using DRK Baden-Württemberg-Hesse CE PCR kits. Analytical sensitivity, analytical specificity and reproducibility/precision were validated and compared with each other in both groups of samples. Results: The analytical sensitivity was 100% for control and post-mortem specimens when spiked with virus standards at concentrations of 3 × level of detection (LOD). Invalid results did not occur. The analytical specificity rate for all assays was 100%. Intra-assay variation was analyzed as a function of sample material and sampling time post mortem. Values of % coefficient of variation (%CV) were comparable for serum and plasma but slightly higher for post-mortem samples especially for those samples collected more than 24 h post mortem. Conclusion: Based on the presented validation, postmortem donor samples can be tested with the automated DRK Baden-Würtemberg-Hesse NAT system.

Postmortem cardiac troponin-I levels predict intramyocardial damage at autopsy

Serum cardiac troponin levels are now widely used in the diagnosis of myocardial infarct (MI) and injury in living patients, but their utility in postmortem diagnosis has not been established. We evaluated postmortem cardiac troponin-I (cTnI) levels in serum from 53 hospital patients undergoing autopsy and correlated the levels with anatomic findings at postmortem examination. Among patients with nonischemic cardiac disease, those with intramyocardial disease (e.g., cardiac transplant rejection, intramyocardial tumor) had significantly higher cTnI levels than those with disease confined to the pericardium (e.g., epicardial tumor implants, pericarditis) (p = 0.004). No correlation was found between recent MI and cTnI level. There was also no correlation between cTnI level and the presence of chronic ischemic features, a history of cardiopulmonary resuscitation, or postmortem interval. We conclude that cTnI is detectable in postmortem serum samples and, although its levels did not correlate specifically with ischemia or infarction in our series, its levels appear to correlate significantly with intramyocardial injury. Use of cardiac troponin in the postmortem diagnosis of cardiac disease may be warranted.

Neuropathology of human immunodeficiency virus 1 infection. Significance of studying in forensic autopsy cases at Dar es Salaam, Tanzania.

In sub-Saharan Africa, only a few studies of neurologic complications of human immunodeficiency virus 1 (HIV-1) infection have been done. The authors studied neuropathology of HIV-1 infection in Tanzania. Forensic autopsy study at Dar es Salaam, Tanzania. A joint research project between Dar es Salaam, Tanzania, and Kumamoto, Japan. Thirty patients with risk factors for HIV-1 infection. Human immunodeficiency virus 1 infection was evaluated by HIV-1 antibody test on postmortem serum samples. The brains of HIV-1-infected persons were studied histopathologically. Infection with HIV-1 was identified on postmortem serum samples in 10 of 30 forensic autopsy cases. Neuropathologic changes of the brain were observed in 8 of the 10 HIV-1-infected persons; these changes consisted of lymphocytic meningitis, bacterial meningoencephalitis, cryptococcal meningoencephalitis, tuberculous meningitis with brain abscesses, and intracerebral hemorrhage. Because none of the persons studied was suspected to have had brain diseases before autopsy, the results suggest that brain diseases of HIV-1-infected patients are likely to go unrecognized in Tanzania. In addition, the high incidence of neuropathologic findings in HIV-1-infected persons indicates that HIV-1-related brain diseases are common in Tanzania, as they are in developed countries. Further forensic autopsy study will determine the range and prevalence of brain complications and have immediate impact on the management of HIV-1-infected patients in Tanzania and other developing countries.

Neuropathology of Human Immunodeficiency Virus 1 Infection Significance of Studying in Forensic Autopsy Cases at Dar es Salaam, Tanzania

○ Objective.-In sub-Saharan Africa, only a few studies of neurologic complications of human immunodeficiency virus 1 (HIV-1) infection have been done. The authors studied neuropathology of HIV-1 infection in Tanzania. Design.-Forensic autopsy study at Dar es Salaam, Tanzania. Setting.-A joint research project between Dar es Salaam, Tanzania, and Kumamoto, Japan. Patients.-Thirty patients with risk factors for HIV-1 infection. Main Outcome Measures.-Human immunodeficiency virus 1 infection was evaluated by HIV-1 antibody test on postmortem serum samples. The brains of HIV-1-infected persons were studied histopathologically. Results.-Infection with HIV-1 was identified on postmortem serum samples in 10 of 30 forensic autopsy cases. Neuropathologic changes of the brain were observed in 8 of the 10 HIV-1-infected persons; these changes consisted of lymphocytic meningitis, bacterial meningoencephalitis, cryptococcal meningoencephalitis, tuberculous meningitis with brain abscesses, and intracerebral hemorrhage. Conclusions.-Because none of the persons studied was suspected to have had brain diseases before autopsy, the results suggest that brain diseases of HIV-1-infected patients are likely to go unrecognized in Tanzania. In addition, the high incidence of neuropathologic findings in HIV-1-infected persons indicates that HIV-1-related brain diseases are common in Tanzania, as they are in developed countries. Further forensic autopsy study will determine the range and prevalence of brain complications and have immediate impact on the management of HIV-1-infected patients in Tanzania and other developing countries.

Higher detection rate of hepatitis G and C virus RNA in liver tissue than in serum of deceased injection drug users.

To examine the prevalence of hepatitis G virus (HGV) and hepatitis C virus (HCV) infections in deceased injection drug users and for comparison of the detection rates of HGV and HCV RNA in liver tissue with detection rates in postmortem serum samples, RT-PCR was performed in 50 drug abuse-related fatalities. HGV RNA was detectable in liver tissue samples from 17/50 suddenly deceased drug abusers (34%). In 16 of these 17 positive cases, serum samples were also available but HGV RNA was detected in only 10. From 29/50 anti-HCV positive individuals, HCV RNA was detected in 23/50 liver tissue samples (46%), but HCV RNA was detectable in only 6/22 of the corresponding serum samples. In 12 anti-HCV positive cases (10 being also positive for HCV RNA in the liver), the examinations revealed a coinfection with HGV by detection of HGV RNA in the liver tissue samples. A significant association between the detection of HCV RNA in the liver and the occurrence of antibodies against the HCV NS4 protein, but not against HCV core antigen or NS3 protein was observed. The probability of anti-HCV and HCV RNA positivity increased with the age of the individuals. No HGV or HCV infection was detected in a control group of 50 persons who died suddenly by violent impact. The prevalence of active HCV and HGV infections in injection drug users detected by RT-PCR in liver tissue is in good accordance with data obtained from sera from living injection drug users. In contrast, the detection rate in postmortem serum samples was clearly lower. Possible reasons for this observation are discussed and the use of liver tissue for postmortem detection of hepatitis virus RNA is recommended.