Usefulness of pericardial and pleural fluids for the postmortem diagnosis of sepsis.

The purpose of this study was to evaluate the postmortem distributions of procalcitonin (PCT), C-reactive protein (CRP), soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) and soluble interleukin-2 receptor (sIL-2R) levels in postmortem serum from femoral blood, pericardial fluid and pleural fluid in a series of sepsis-related fatalities (12 subjects) and control cases (20 subjects) that underwent medico-legal investigations. Our aim was to assess the diagnostic potential of the results obtained from pericardial and pleural fluid analysis in identifying sepsis-related deaths. All sepsis-related cases had a documented, clinical diagnosis that was established in vivo during hospitalization. Pneumonia was the main infectious focus identified during autopsy and histology. Pseudomonas aeruginosa, Klebsiella pnemoniae and Escherichia coli were the most commonly identified bacteria in blood and lung tissue cultures. The preliminary results corroborate the usefulness of PCT, CRP, sTREM-1 and sIL-2R determination in postmortem serum for the identification of sepsis-related deaths. Moreover, the data suggest that, as far as PCT, CRP, sTREM-1 and sIL-2R measurements are concerned, pericardial and pleural fluids can be considered suitable alternatives to postmortem serum should femoral blood prove unavailable at autopsy.

Postmortem measurement of human chorionic gonadotropin in vitreous humor and bile.

Postmortem human chorionic gonadotrophin (HCG) blood assay can confirm postmortem diagnosis of pregnancy or document situations in which HCG levels are elevated. In some cases, however, blood sampling is not possible at autopsy. In this study, HCG was quantified by enzyme-linked fluorescent assay (ELFA) in the bile (n = 5), vitreous humor (n = 4), and postmortem blood (n = 4) of five pregnant women. There were no false negatives in the pregnant subjects (n = 5) or false positives in controls (n = 34), enabling this test to be recommended for routine use in forensic contexts in which the detection of elevated HCG levels could be of interest.

Postmortem magnetic resonance imaging of the heart ex situ: development of technical protocols.

Postmortem MRI (PMMR) examinations are seldom performed in legal medicine due to long examination times, unfamiliarity with the technique, and high costs. Furthermore, it is difficult to obtain access to an MRI device used for patients in clinical settings to image an entire human body. An alternative is available: ex situ organ examination. To our knowledge, there is no standardized protocol that includes ex situ organ preparation and scanning parameters for postmortem MRI. Thus, our objective was to develop a standard procedure for ex situ heart PMMR examinations. We also tested the oily contrast agent Angiofil® commonly used for PMCT angiography, for its applicability in MRI. We worked with a 3 Tesla MRI device and 32-channel head coils. Twelve porcine hearts were used to test different materials to find the best way to prepare and place organs in the device and to test scanning parameters. For coronary MR angiography, we tested different mixtures of Angiofil® and different injection materials. In a second step, 17 human hearts were examined to test the procedure and its applicability to human organs. We established two standardized protocols: one for preparation of the heart and another for scanning parameters based on experience in clinical practice. The established protocols enabled a standardized technical procedure with comparable radiological images, allowing for easy radiological reading. The performance of coronary MR angiography enabled detailed coronary assessment and revealed the utility of Angiofil® as a contrast agent for PMMR. Our simple, reproducible method for performing heart examinations ex situ yields high quality images and visualization of the coronary arteries.

When gas analysis assists with postmortem imaging to diagnose causes of death.

Postmortem imaging consists in the non-invasive examination of bodies using medical imaging techniques. However, gas volume quantification and the interpretation of the gas collection results from cadavers remain difficult. We used whole-body postmortem multi-detector computed tomography (MDCT) followed by a full autopsy or external examination to detect the gaseous volumes in bodies. Gases were sampled from cardiac cavities, and the sample compositions were analyzed by headspace gas chromatography-mass spectrometry/thermal conductivity detection (HS-GC-MS/TCD). Three categories were defined according to the presumed origin of the gas: alteration/putrefaction, high-magnitude vital gas embolism (e.g., from scuba diving accident) and gas embolism of lower magnitude (e.g., following a traumatic injury). Cadaveric alteration gas was diagnosed even if only one gas from among hydrogen, hydrogen sulfide or methane was detected. In alteration cases, the carbon dioxide/nitrogen ratio was often >0.2, except in the case of advanced alteration, when methane presence was the best indicator. In the gas embolism cases (vital or not), hydrogen, hydrogen sulfide and methane were absent. Moreover, with high-magnitude vital gas embolisms, carbon dioxide content was >20%, and the carbon dioxide/nitrogen ratio was >0.2. With gas embolisms of lower magnitude (gas presence consecutive to a traumatic injury), carbon dioxide content was <20% and the carbon dioxide/nitrogen ratio was often <0.2. We found that gas analysis provided useful assistance to the postmortem imaging diagnosis of causes of death. Based on the quantifications of gaseous cardiac samples, reliable indicators were determined to document causes of death. MDCT examination of the body must be performed as quickly as possible, as does gas sampling, to avoid generating any artifactual alteration gases. Because of cardiac gas composition analysis, it is possible to distinguish alteration gases and gas embolisms of different magnitudes.

Postmortem diagnosis of diabetes mellitus and its complications.

Diabetes mellitus has become a major cause of death worldwide and diabetic ketoacidosis is the most common cause of death in children and adolescents with type 1 diabetes. Acute complications of diabetes mellitus as causes of death may be difficult to diagnose due to missing characteristic macroscopic and microscopic findings. Biochemical analyses, including vitreous glucose, blood (or alternative specimen) beta-hydroxybutyrate, and blood glycated hemoglobin determination, may complement postmortem investigations and provide useful information for determining the cause of death even in corpses with advanced decompositional changes. In this article, we performed a review of the literature pertaining to the diagnostic performance of classical and novel biochemical parameters that may be used in the forensic casework to identify disorders in glucose metabolism. We also present a review focusing on the usefulness of traditional and alternative specimens that can be sampled and subsequently analyzed to diagnose acute complications of diabetes mellitus as causes of death.

Postmortem angiography using femoral cannulation and postmortem microbiology.

Despite the undeniable advantages of postmortem angiography, numerous questions have arisen concerning the influence that the injected contrast media may exercise on biological fluids and tissues collected for toxicological and biochemical investigations. Moreover, cardiac blood for microbiological investigations cannot be obtained post-angiography. In this study, we examined whether the peripheral blood collected prior to postmortem angiography, using percutaneous access to femoral vessels after skin surface disinfection, could be suitable for microbiological investigations when postmortem angiography with femoral vessel cannulation is also performed. A total of 66 cases were included in the study and were divided into two subgroups (angiography and bacteriology group, 33 cases and control group, 33 cases). Autopsies, histology, toxicology, bacteriology, and biochemical investigations (procalcitonin, C-reactive protein, interleukin-6, and soluble triggering receptors expressed on myeloid cells type 1) were performed in all cases. No statistically significant differences between the two groups were noted, and identified category distribution (death unrelated to infection, true infection, false positive, and undetermined) was rather similar in both studied populations. These preliminary results suggest that postmortem angiography using a femoral approach does not constitute an impediment to the collection of peripheral blood for microbiology and vice versa. Moreover, the use of femoral blood for microbiology does not lead to an increased risk of doubtful results.

Postmortem serum protein growth arrest-specific 6 levels in sepsis-related deaths.

Growth arrest-specific 6 (Gas6) is widely expressed in leukocytes, platelets, endothelial cells, and monocytes. It regulates various processes including granulocyte adhesion to the endothelium, cell migration, thrombus stabilization, and cytokine release. In humans, increased plasma Gas6 levels have been described in patients with sepsis and septic shock. In this study, Gas6 concentrations were measured in postmortem serum from femoral blood in a series of sepsis-related fatalities and control cases. The aims were twofold: first, to determine whether Gas6 can be reliably determined in postmortem serum; and second, to assess its diagnostic potential in identifying sepsis-related deaths. Two study groups were prospectively formed, a sepsis-related fatalities group (24 cases) and a control group (24 cases) including cases of deep vein thrombosis and fatal pulmonary embolism, cases of systemic inflammatory response syndrome in severe trauma, cases of end-stage renal failure, and cases of hanging (non-septic, non-SIRS, non-end stage renal failure cases). The preliminary results of this study seem to indicate that Gas6 can be effectively measured in postmortem serum. However, Gas6 levels in sepsis-related fatalities do not appear to be clearly distinguishable from concentrations in pulmonary embolism, severe trauma, and end-stage renal failure cases. These findings tend to support previous reports that indicated that Gas6 behaves as an acute phase reactant and can be considered a general marker of inflammation rather than a specific biomarker of sepsis.

Multiphase Postmortem Computed Tomography Angiography in Pediatrics: A Case Report.

Postmortem imaging techniques, especially postmortem computed tomography, have become integral tools in forensic investigations. Multiphase postmortem computed tomography angiography (MPMCTA) visualizes the vascular system in detail and makes it possible to evaluate the perfusion of even the smallest vessels. Although the technique has been well described for adults, no pediatric cases have been reported and no pediatric protocol has been established for this type of investigation. We present the case a 7-year-old child for which we used a previously described MPMCTA protocol and adapted values of perfusion, with the same technical equipment as for adult cases. Our main objective was to propose a perfusion protocol adapted for the investigation of infants and children. Moreover, we discuss both the difficulties that we encountered and possible ways to further improve the investigation of pediatric cases by MPMCTA.

Erratum of initial paper: Postmortem computed tomography angiography vs. conventional autopsy: advantages and inconveniences of each method.

PURPOSE: Postmortem computed tomography angiography (PMCTA) was introduced into forensic investigations a few years ago. It provides reliable images that can be consulted at any time. Conventional autopsy remains the reference standard for defining the cause of death, but provides only limited possibility of a second examination. This study compares these two procedures and discusses findings that can be detected exclusively using each method. MATERIALS AND METHODS: This retrospective study compared radiological reports from PMCTA to reports from conventional autopsy for 50 forensic autopsy cases. Reported findings from autopsy and PMCTA were extracted and compared to each other. PMCTA was performed using a modified heart-lung machine and the oily contrast agent Angiofil® (Fumedica AG, Muri, Switzerland). RESULTS: PMCTA and conventional autopsy would have drawn similar conclusions regarding causes of death. Nearly 60 % of all findings were visualized with both techniques. PMCTA demonstrates a higher sensitivity for identifying skeletal and vascular lesions. However, vascular occlusions due to postmortem blood clots could be falsely assumed to be vascular lesions. In contrast, conventional autopsy does not detect all bone fractures or the exact source of bleeding. Conventional autopsy provides important information about organ morphology and remains the only way to diagnose a vital vascular occlusion with certitude. CONCLUSION: Overall, PMCTA and conventional autopsy provide comparable findings. However, each technique presents advantages and disadvantages for detecting specific findings. To correctly interpret findings and clearly define the indications for PMCTA, these differences must be understood.

Postmortem diagnosis of anaphylaxis in presence of decompositional changes.

Eosinophil and activated mast cell identification in the spleen combined with mast cell tryptase determination in postmortem serum may diagnose fatal anaphylaxis with a high degree of certainty. Mast cell tryptase measurement and significance in corpses with decompositional changes remains however an issue of controversy. Analogously, immunohistochemistry in corpses with decompositional changes may be influenced by several mechanisms, including protein alteration, antigen diffusion and unspecific antibody binding to disrupted protein structures. The authors present an autopsy case involving a 55-year-old woman who unintentionally received clarithromycin. Due to difficult in administrative procedures, the postmortem examination was performed 96 h after death. Mast cell tryptase was measured in postmortem serum from femoral, aortic and right heart blood. The obtained results were consistent with mast cell activation. Histochemistry (Pagoda Red) and immunohistochemistry (anti-tryptase antibodies) allowed splenic eosinophils and mast cells to be detected. Based on the results of all postmortem investigations, the hypothesis of anaphylaxis following accidental clarithromycin administration was formulated.

Fibrinonecrotic enteritis of piglets in a commercial farm: a postmortem study of the prevalence and the role of lesion associated agents Isospora suis and Clostridium perfringens

The objectives were to determine the prevalence of fibrinonecrotic enteritis (FNE) on a farrow-to-finish farm of 1,000 sows, to categorize the pathological changes, and to to investigate the lesion associated agents Isospora suis and Clostridium perfringens. Causes of preweaning mortality (PWM) were classified into 8 categories including FNE. Obtained data were evaluated for statistical significance by adjusted Chi-square analysis. Samples of FNE were taken for complementary studies including a PCR technique for genotyping toxin genes of Clostridium perfringens from gut samples fixed in 10% neutral formalin. From 3,153 piglets examined, less than 1% was classified as FNE. FNE prevalence increased progressively from the first to the third week, the last differing statistically from the others. Eighty percent of gut samples with FNE lesions were positive to Isospora suis, when examined by PCR from 9 severe FNE lesions detected 7 positive samples only for a toxin gene, characteristic of C. perfringens type-A.

Postmortem findings in collared peccaries raised in captivity in northeastern Brazil

This study is a retrospective examination of diseases in collared peccaries that were diagnosed by the Veterinary Pathology Laboratory, Universidade Federal Rural do Semiárido. Necropsy and histological examination were performed from 2005 to 2010. Of the 50 necropsied collared peccaries, 24% died due to restraint and capture myopathy; 18% died from trauma; and the remainder was diagnosed with splenic hemangioma (6%), enterolithiasis (6%), gastritis (6%), gastric ulcer (4%), intestinal volvulus (4%), gastric volvulus (2%), mammary carcinoma (2%), polycystic kidney disease (2%), pyometra (2%), and suppurative bronchopneumonia (2%). Twelve animals remained undiagnosed, seven of which (14%) were in advanced autolytic condition and five of which (10%) had no gross or microscopic lesions that were compatible with disease. This paper describes illnesses that have not been reported in the collared peccary, focusing on their clinical and pathological aspects.