Heart Weight Is an Independent Factor Associated With, But Is a Poor Predictor for, Sudden Cardiac Death.

ABSTRACT: An enlarged heart can cause electrical instability and impaired contractility, leading to fatal arrhythmia and acute heart failure, and is associated with sudden cardiac death. However, there is limited postmortem evidence on whether heart weight is an independent factor associated with sudden cardiac death. This 18-month retrospective study examined 108 adult heart weights in which all the hearts were weighed after dissection, blood and blood clots removed, rinsed in water, and pat dried. The multivariate logistic regression analysis showed heart weight was an independent factor associated with sudden cardiac death. However, after normalization, the heart weight was a poor predictor of sudden cardiac death with an area under the curve less than 0.7 in the plotted receiver operating characteristic curve.

Terminal Ileum Perforation: A Rare Complication of Verocytotoxigenic Escherichia coli Infection in an Adult With Prader-Willi Syndrome.

ABSTRACT: Intestinal perforation is an uncommon complication and presentation of verocytotoxigenic Escherichia coli (VTEC) infection in individuals with Prader-Willi syndrome (PWS). The common site of perforation from VTEC infection is in the colon (and almost exclusively in the pediatric population), whereas PWS is in the stomach. Terminal ileum perforation is uncommon and is not reported in either these 2 conditions. We report a death from terminal ileum perforations in an adult who had PWS and was infected with VTEC. Potential reasons why the perforation occurred at this rare location, rather than in other more common location, in an adult are discussed.

Hemorrhagic Pseudocyst: A Rare Cerebral Mass Lesion Causing Death. A Case Report and Brief Review of Literature.

ABSTRACT: Mass lesions in the brain encompass a wide range neoplastic and nonneoplastic entities. These can present as a diagnostic pitfall, with nonspecific, overlapping symptoms and similar appearances on radiology. They may cause death through varied mechanisms, either specific to the underlying pathophysiology or due to the space-occupying effect of the lesion. We report a case of fatal hemorrhagic cerebral pseudocyst, a rare mass lesion, associated with a cerebral varix, causing death in a morbidly obese individual. To the best of our knowledge, there is no previous documentation in the postmortem literature of this entity as a cause of death. This case aims to document this rare entity in the differential diagnosis of a tumor-like lesion in the brain, highlight the clinical difficulty in its assessment, and demonstrate an uncommon mechanism of death, of a mass lesion acting as a focus causing seizures, with resulting hypoxia due to effects of morbid obesity and heart failure.

A 5-Year Retrospective Study on Infant Homicide Presenting as Cot Death: Are We Missing Infant Homicides?

ABSTRACT: Being found dead in cot or bed is the most common presentation encountered with infant deaths. These deaths are often associated with unsafe sleep environment. The postmortem examination in such cases is often negative, and along with family objections, cultural, and other factors, may lead to a coroner considering not authorizing a postmortem examination. However, not identifying a homicide is a potential risk if a postmortem examination is not performed. This 5-year retrospective study investigated the proportion of infant homicide death initially presenting as cot death. Of a total of 103 cases of infants initially presenting as being found dead in cot or bed, 3 (approximately 3%) were classified as homicides after postmortem examination. During the study period, a total of 9 infant homicides were reported, translating to 33% (3 of 9) of infant homicides presented as cot deaths. Postmortem radiology was a valuable adjunct, but was unable to recognize 2 of the homicide cases with traumatic head injuries (with subdural hemorrhage and brain injury only). We strongly advocate that all infant deaths presenting as cot death require a full postmortem examination.

Classifying Microscopic Acute and Old Myocardial Infarction Using Convolutional Neural Networks.

ABSTRACT: Convolutional neural network (CNN) has advanced in recent years and translated from research into medical practice, most notably in clinical radiology and histopathology. Research on CNNs in forensic/postmortem pathology is almost exclusive to postmortem computed tomography despite the wealth of research into CNNs in surgical/anatomical histopathology. This study was carried out to investigate whether CNNs are able to identify and age myocardial infarction (a common example of forensic/postmortem histopathology) from histology slides. As a proof of concept, this study compared 4 CNNs commonly used in surgical/anatomical histopathology to identify normal myocardium from myocardial infarction. A total of 150 images of the myocardium (50 images each for normal myocardium, acute myocardial infarction, and old myocardial infarction) were used to train and test each CNN. One of the CNNs used (InceptionResNet v2) was able to show a greater than 95% accuracy in classifying normal myocardium from acute and old myocardial infarction. The result of this study is promising and demonstrates that CNN technology has potential applications as a screening and computer-assisted diagnostics tool in forensic/postmortem histopathology.

Differences Between Central and Peripheral Postmortem Tryptase Levels.

ABSTRACT: Postmortem tryptase is a commonly used biochemical test to aid in the diagnosis of fatal anaphylaxis, which is currently recommended to be sampled from peripheral (femoral) veins because of a research showing comparatively elevated levels from central blood sources. Previous studies have used nonstandardized or nondocumented sampling methods; however, more recent research demonstrates that tryptase levels may vary depending on the sampling method. This study used the recommended sampling method of aspirating the femoral vein after clamping and compared in a pairwise comparison with aspiration of central venous and arterial blood sources (inferior vena cava and aorta) in 2 groups of 25 nonanaphylactic deaths. We found no statistically significant differences in postmortem tryptase between central and femoral vein blood; however, sporadic outliers in central blood (particularly aortic blood reaching levels above documented cutoffs for fatal anaphylaxis) were observed. Our findings provide evidence for the existing recommendations that femoral vein blood remains the preferred sample for postmortem tryptase over central blood.

Ruptured Esophageal Varices From Metastatic Tumor in the Liver: A Case Report and Brief Review of Literature.

Ruptured esophageal varices can present as sudden death from gastrointestinal hemorrhage. The most common underlying pathology causing esophageal varices is cirrhosis leading to portal hypertension. However, not all esophageal varices arise from portal hypertension, and not all portal hypertensions are caused by cirrhosis. We present a rare case of ruptured esophageal varices casing death in an individual with metastatic tumor (high-grade) neuroendocrine tumor in the liver causing portal hypertension. This is, to the best of our knowledge, the first case report in the literature reporting a neuroendocrine tumor causing esophageal varices. This case report aims to document this rather rare entity, highlight another mechanism on how metastatic disease can result in sudden death, and give a brief review of literature on metastatic tumor in the liver causing esophageal varices.

Combining Postmortem Cerebrospinal Fluid Biochemistry With Lung-to-Body Ratio to Aid the Diagnosis of Salt Water Drowning.

Diagnosing drowning as a cause of death can pose many challenges for the forensic pathologist and a number of ancillary tests have been proposed to assist in the diagnosis, whether the body was in salt water or fresh water. Although elevated vitreous humor sodium and chloride is a reliable marker, its limitation to prolonged immersion has resulted in the recent investigation of cerebrospinal fluid (CSF) sodium and chloride as alternative matrix in cases of longer or unknown immersion times. This study investigated postmortem CSF from lumbar puncture (CSF_L_Na_Cl) and ventricular aspiration (CSF_Vent_Na_Cl), as well as lung/body (LB) ratio in the diagnosis of salt water drowning and performed comparison and combination testing of methods to improve diagnostic accuracy of the drowning diagnosis. This study found that CSF_L_Na_Cl was the most accurate method (89%) in the given cohort, but that CSF_Vent_Na_Cl and LB combined was the second most accurate method (83%), exceeding CSF_Vent_Na_Cl (77%) and LB (81%) used alone. These findings are useful for stratifying and prioritizing postmortem samples in the investigation of salt water drowning and also have significance for future studies using this methodology to combine and compare the accuracy of different investigations.

Nonrheumatoid Fibrinous Pericarditis: A Medical Examiner Algorithm for the Diagnosis of Viral Myocarditis and Use of Molecular Diagnostic Techniques.

Classic "bread-and-butter" appearance of fibrinous pericarditis had been described in rheumatic disease and other immunologic diseases such as systemic lupus erythematosus, post-myocardial infarct, uremia, tuberculosis, radiation effects, bacterial, and viral etiology. In most of the described cases, pericarditis occurs as a delayed complication. We present a case of a 21-year-old white woman who was seen in the emergency department to rule out pulmonary embolism for shortness of breath, chest pain, and lightheadedness. The autopsy showed a collection of serous fluid into the pericardial sac with bread-and-butter appearance. Microscopically, the pericardium showed acute inflammation with fibrinous exudates. Sections of the heart showed areas of lymphocytic infiltration with acute fibrinous inflammation of the pericardium. Vasculitis was seen in small blood vessels in the heart and was negative in other organs. No granuloma or necrotizing lesion was seen in microscopic sections of all organs including the heart, ruling out rheumatologic disease. The present study highlights the quest and design of an algorithm for a nonrheumatic disorder as the cause of pericarditis. Molecular studies were performed on heart tissue blocks for identification of cardiotropic viruses. Human parvovirus B19 was isolated from heart tissue blocks. The present case study highlights on updates in pathophysiology and diagnostic criteria for myocarditis along with the use of new molecular techniques for detection of idiopathic cardiomyopathies in a medical examiner setup.

Black Esophagus (Acute Necrotizing Esophagitis) and Wischnewsky Lesions in a Death From Diabetic Ketoacidosis: A Possible Underlying Mechanism.

Acute esophageal necrosis (AEN), also known as black esophagus, is a rare clinical entity. It is recently described to be associated with diabetic ketoacidosis (DKA) in a few case reports. Wischnewsky lesions (WLs) are a classic postmortem finding seen in fatal hypothermia but are recently described to be associated with DKA. Interestingly, the pathogenesis and morphology of AEN and WLs appear to share similar characteristics. Both AEN and WLs are reported to be seen simultaneously in hypothermic deaths and deaths related to alcohol abuse, but not in DKA. We report a death in a 67-year-old woman who died of DKA. At postmortem examination, the esophagus and stomach showed AEN and WLs, respectively. Although not previously reported together, both AEN and WLs have separately been described in cases of DKA. This case raises a possible unifying etiology of AEN and WLs in DKA (and probably also in hypothermic deaths and deaths related to alcohol abuse), manifested in different parts of the gastrointestinal tract.

Elevated Cerebrospinal Fluid Sodium and Chloride Levels in a Saltwater Drowning Death.

To ascribe a cause of death from drowning in a body immersed in water can be difficult because of the absence of specific postmortem findings and unreliable ancillary tests. Postmortem vitreous biochemical analysis is documented to be a useful adjunct ancillary test to aid the diagnosis of saltwater drowning. A major confounding factor in using postmortem vitreous is the effect of electrolyte diffusion and water osmosis during immersion. A recent animal study suggested that cerebrospinal fluid (CSF) biochemical analysis, which is unaffected by immersion, may be an alternative. However, to date, there are no human data to support this. We report a saltwater drowning death from presumed suicide in which the postmortem CSF sodium and chloride level was elevated compared with nonimmersion deaths. This case gives evidence to support the potential use of postmortem CSF sodium and chloride level as an adjunct to the diagnosis of saltwater drowning.

Rapid Streptococcus Pneumonia Antigen Detection on Postmortem Urine in a Death Due to Pneumococcal Meningitis.

Streptococcus pneumoniae is the leading cause of adult bacterial meningitis. Differing from Neisseria meningitidis (the second most common cause of acute bacterial meningitis), contact tracing and chemoprophylaxis are not required. At postmortem, the differentiation between S. pneumoniae and N. meningitidis is traditionally done by culture and polymerase chain reaction performed on blood or cerebrospinal fluid, but may take hours, if not days, to analyze. We present a death from bacterial meningitis in a 73-year-old woman in which a rapid urinary pneumococcal antigen testing was able to identify S. pneumoniae as the causative organism within 1 hour. This was confirmed by subsequent brain swab culture. The rapid urinary pneumococcal antigen test in the case prevented the need for contact tracing and chemoprophylaxis. This case highlights the potential use of this test to rapidly identify the culprit organism at postmortem examination when acute bacterial meningitis is detected.

Neisseria meningitidis Isolated in Vitreous Humor in a 5-Month-Old Infant Death From Meningococcal Sepsis.

Diagnosing sepsis at postmortem is challenging. With respect to meningococcal sepsis, the postmortem microbiological identification of Neisseria meningitidis is nearly always due to true infection, including in cases of decomposition. Previous case series and case reports were able to isolate N. meningitidis in vitreous humor in adult deaths from meningococcal sepsis when blood and/or cerebrospinal fluid was unavailable. It was suggested that vitreous humor polymerase chain reaction (PCR) may be useful in the diagnosis of meningococcal sepsis. We describe a fatal case of meningococcal sepsis in a 5-month-old infant where N. meningitidis was detected in vitreous humor, cerebrospinal fluid, and blood through PCR. The presented case report gives further evidence in the potential use of vitreous PCR analysis in suspected meningococcal sepsis, particularly in the pediatric population.

Biochemical Differences Between Vitreous Humor and Cerebral Spinal Fluid in a Death From Diabetic Ketoacidosis.

Biochemical analysis of cerebrospinal fluid (CSF) and vitreous humor (VH) forms an important diagnostic ancillary test at autopsy. Cerebrospinal fluid can be sampled from the ventricular system (VA) and from lumbar puncture (LP), whereas VH can be sampled from the orbits. Biochemical electrolytes seem to vary between VH and CSF collected from different sites, but whether there is any difference in glucose and ß-hydroxybutyrate is unclear. We present a case report of a 21-year-old man who died of diabetic ketoacidosis confirmed at autopsy. Ventricular system, LP, and VH were biochemically analyzed and showed that glucose was highest in VH (41 mmol/L) and was 6 and 8 mmol/L higher than CSF in the LP and VA, respectively. ß-Hydroxybutyrate was also highest in VH (20 mmol/L) and was 5 and 6 mmol/L higher than LP and VA, respectively. Our findings suggest that postmortem CSF glucose and ß-hydroxybutyrate may not truly reflect that of VH and vary between CSF sampling sites.

Postmortem Tryptase Level in 120 Consecutive Nonanaphylactic Deaths: Establishing a Reference Range as <23 µg/L.

Postmortem tryptase is a useful biochemical test to aid the diagnosis of anaphylaxis. Multiple perimortem and postmortem factors have been documented to cause an elevation in postmortem tryptase level. One factor that was recently recognized to have an impact on postmortem tryptase level is correct sampling technique. A recent study recommended aspirating blood samples from a clamped femoral/external iliac vein to be used for reliable postmortem tryptase analysis. This study sampled 120 consecutive nonanaphylactic deaths in which all the peripheral bloods were sampled as recommended. Postmortem interval, resuscitation, different nonanaphylactic causes of death, sex, and age did not show any statistical significant relation to postmortem tryptase level in Student t test, Pearson correlation, and univariate and multivariate analyses. The mean (SD) postmortem tryptase level was 8.4 (5.2) µg/L (minimum, 1.0 µg/L; maximum, 36.1 µg/L; median, 7.3 µg/L). Using nonparametric methods, the postmortem tryptase reference range in nonanaphylactic death was established as <23 µg/L (97.5th percentile).

Elevation of Postmortem Cerebrospinal Fluid Sodium and Chloride Levels Is a Potential Adjunct Test in the Diagnosis of Salt Water Drowning.

Postmortem vitreous humor biochemistry is a useful test in the diagnosis of salt water drowning (SWD). A significant limitation of vitreous humor is the potential effect of prolonged immersion. A recent animal study and case report suggested that cerebrospinal fluid biochemistry may be an alternative to vitreous because it is more resistant to the effects of immersion, given its protected anatomical location. This study compared postmortem cerebrospinal fluid sodium and chloride (PMCSC) levels collected via ventricular aspiration (PMCSC_V) and via lumbar puncture (PMCSC_L) in 13 SWD and 31 nonimmersion deaths. It showed a significant elevation in PMCSC levels in SWD deaths for both PMCSC_V and PMCSC_L (P < 0.05). The areas under the curve on the receiver operating characteristic curves for PMCSC_V and PMCSC_L were 0.73 and 0.83, respectively. The optimal cutoff for PMCSC_V was 216 mmol/L (sensitivity, 0.60; specificity, 0.72; likelihood ratio, 1.80; positive predictive value, 0.45) and for PMCSC_L was 241 mmol/L (sensitivity, 0.78; specificity, 0.73; likelihood ratio, 2.89; positive predictive value, 0.46). This study supports PMCSC levels as another biochemical test that can potentially aid in the diagnosis of SWD, particularly in cases where vitreous humor samples are unavailable or uninterpretable.

Accidental Carbon Monoxide Poisoning While Driving: A Case Report With Review of the Literature.

Carbon monoxide (CO) is the cause of a significant percentage of fatal poisonings in many countries. It is known that fatalities resulting from CO poisoning are underreported and/or misclassified. Carbon monoxide exposure while driving can occur due to faulty exhaust systems, defective ventilation systems, emission from other vehicles, and even cigarette smoking. We report the case of a 23-year-old woman who was involved in a low-speed motor vehicle collision and was found unresponsive in her vehicle due to CO poisoning. A review of the literature revealed rare vehicle-related accidental CO poisonings.

Basal Subnuclear Vacuolization, Armanni-Ebstein Lesions, Wischnewsky Lesions, and Elevated Vitreous Glucose and ß-Hydroxybuyrate: Is It Hypothermia, Diabetic Ketoacidosis, or Both?

Hypothermia and diabetic ketoacidosis are both potentially fatal conditions, which have historically been considered to have associated pathognomonic pathologies. Hypothermia and diabetic ketoacidosis share similar pathological mechanisms, which result in metabolic derangement, with increased post mortem vitreous glucose and ß-hydroxybuyrate, and are able to exacerbate and precipitate one another. Although Wischnewsky lesions are associated with hypothermia, and Armanni-Ebstein lesions and basal subnuclear vacuolization are associated with diabetic ketoacidosis, recent studies have demonstrated that there is a significant overlap between the pathological findings of these 2 conditions. We report a case of a 50-year-old woman with type 1 diabetes who was found deceased in the middle of winter. Autopsy showed Wischnewsky lesions, Armanni-Ebstein lesions, and basal subnuclear vacuolization, together with elevated vitreous glucose and ß-hydroxybuyrate. The cause of death was the combined effects of hypothermia and diabetic ketoacidosis. This case highlights the overlapping clinical presentation, pathophysiology, and pathology of these 2 conditions.

Empty Delta Sign on Unenhanced Postmortem Computed Tomography Scan in Cerebral Venous Thrombosis.

Cerebral venous thrombosis is a rare condition which constitutes 0.5% to 2% of all types of stroke and carries a mortality of up to 20% to 50%. It leads to cerebral edema, infarction, hemorrhage and venous hypertension. Clinically the diagnosis is confirmed using enhanced computed tomography (CT) angiography which demonstrates an empty delta sign in cerebral veins, particularly in the superior sagittal sinus. However, postmortem CT (PMCT) findings on cerebral venous thrombosis have not been documented in the literature. We present a case report of a 69-year-old man who on unenhanced PMCT scan showed an empty delta sign in the cerebral veins. The empty delta sign was able to be demonstrated in unenhanced PMCT which can be explained by hyper attenuation of the dural veins at postmortem forming an internal contrast highlighting the thrombus.

A Rare Case of Isolated Atrial Myocarditis Causing Death With no Post Mortem Computed Tomography Scan Correlation.

Acute myocarditis is a potentially fatal cardiac pathology that is thought to cause sudden death through arrhythmia and cardiac failure. Of the different subtypes, lymphocytic myocarditis is the most common form. The pathophysiology of myocarditis can be generally diffuse or focally involve the ventricles, but less frequently affects the atria. Although the clinical literature reports isolated atrial myocarditis as a cause of atrial fibrillation and enlargement, there is scant postmortem literature on the findings of this pathology. We report a fatal case of isolated lymphocytic atrial myocarditis affecting only the left atrium in a 56-year-old man, where microscopy of the left atrium confirmed a florid lymphocytic myocarditis. Retrospective postmortem computed tomography scan review did not show any abnormalities on the left atrial wall.