Diffuse alveolar damage (DAD) resulting from coronavirus disease 2019 Infection is Morphologically Indistinguishable from Other Causes of DAD.

AIMS: Diffuse alveolar damage (DAD) is a ubiquitous finding in inpatient coronavirus disease 2019 (COVID-19)-related deaths, but recent reports have also described additional atypical findings, including vascular changes. An aim of this study was to assess lung autopsy findings in COVID-19 inpatients, and in untreated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive individuals who died in the community, in order to understand the relative impact of medical intervention on lung histology. Additionally, we aimed to investigate whether COVID-19 represents a unique histological variant of DAD by comparing the pathological findings with those of uninfected control patients. METHODS AND RESULTS: Lung sections from autopsy cases were reviewed by three pulmonary pathologists, including two who were blinded to patient cohort. The cohorts included four COVID-19 inpatients, four cases with postmortem SARS-CoV-2 diagnoses who died in the community, and eight SARS-CoV-2-negative control cases. DAD was present in all but one SARS-CoV-2-positive patient, who was asymptomatic and died in the community. Although SARS-CoV-2-positive patients were noted to have more focal perivascular inflammation/endothelialitis than control patients, there were no significant differences in the presence of hyaline membranes, fibrin thrombi, airspace organisation, and 'acute fibrinous and organising pneumonia'-like intra-alveolar fibrin deposition between the cohorts. Fibrinoid vessel wall necrosis, haemorrhage and capillaritis were not features of COVID-19-related DAD. CONCLUSIONS: DAD is the primary histological manifestation of severe lung disease in COVID-19 patients who die both in hospital and in the community, suggesting no contribution of hyperoxaemic mechanical ventilation to the histological changes. There are no distinctive morphological features with which to confidently differentiate COVID-19-related DAD from DAD due to other causes.

Ultrastructural Evidence for Direct Renal Infection with SARS-CoV-2.

BACKGROUND: A significant fraction of patients with coronavirus disease 2019 (COVID-19) display abnormalities in renal function. Retrospective studies of patients hospitalized with COVID-19 in Wuhan, China, report an incidence of 3%-7% progressing to ARF, a marker of poor prognosis. The cause of the renal failure in COVID-19 is unknown, but one hypothesized mechanism is direct renal infection by the causative virus, SARS-CoV-2. METHODS: We performed an autopsy on a single patient who died of COVID-19 after open repair of an aortic dissection, complicated by hypoxic respiratory failure and oliguric renal failure. We used light and electron microscopy to examine renal tissue for evidence of SARS-CoV-2 within renal cells. RESULTS: Light microscopy of proximal tubules showed geographic isometric vacuolization, corresponding to a focus of tubules with abundant intracellular viral arrays. Individual viruses averaged 76 µm in diameter and had an envelope studded with crown-like, electron-dense spikes. Vacuoles contained double-membrane vesicles suggestive of partially assembled virus. CONCLUSIONS: The presence of viral particles in the renal tubular epithelium that were morphologically identical to SARS-CoV-2, and with viral arrays and other features of virus assembly, provide evidence of a productive direct infection of the kidney by SARS-CoV-2. This finding offers confirmatory evidence that direct renal infection occurs in the setting of AKI in COVID-19. However, the frequency and clinical significance of direct infection in COVID-19 is unclear. Tubular isometric vacuolization observed with light microscopy, which correlates with double-membrane vesicles containing vacuoles observed with electronic microscopy, may be a useful histologic marker for active SARS-CoV-2 infection in kidney biopsy or autopsy specimens.

A Retrospective Study of the Investigation of Homicidal Childhood Asphyxial Deaths.

As one of the leading causes of traumatic deaths in newborns, infants, and young children, there is no anatomic or microscopic feature that is pathognomonic for asphyxial deaths. Instead, pathologists rely on investigation information, including confessions and/or witness statements, and potential evidence at the scene. Twenty cases of homicidal newborn, infant, and young children asphyxial deaths were reviewed, which included death and police investigation reports and autopsy reports, as well as histology slides of lung sections. This series of homicidal asphyxial deaths highlight that, in a vast majority of such cases, the final cause and manner of death rulings are dependent on confession by the perpetrator. Furthermore, this series highlights the possible role of histology to help forensic pathologists better certify asphyxial deaths. Finally, this series emphasizes important investigation points and considerations at autopsy during the investigation of asphyxial deaths in newborns, infants, and young children.

Micro Disasters: The Case of Serial Killer Jeffrey Dahmer.

Disasters are commonly experienced as major devastating events that exceed the resources of an agency to respond, with effects emanating throughout a community or region. There are, however, those events that are more measured, more subtle, and with few actual deaths, which still distract investigators from their daily duties and routines and project long lasting and crippling effects to a community or nation. Disasters can occur from natural forces or be the result of human activity. Most forensic pathologists who practice over a significant time will encounter one or the other types of disaster, sometimes more than a few. In my own career, I have witnessed large-scale disasters, such as hundreds of deaths occurring as the result of a major heat wave, to small-scale disasters such as factory explosions or small airplane crashes at sea-each with their own challenges. In addition to the extent of the initial disaster, many require the detailed, exhaustive evidentiary recovery and examination of a crime scene. The Jeffrey Dahmer case, although only involving 11 actual victims, required a major disaster response, and continues to influence and affect a community over 25 years later.

Prostatic Adenocarcinoma With Hormone Exposure Related Changes in a Patient With Hepatic Cirrhosis - Value of Autopsy in a Case Report.

Hepatic cirrhosis is commonly associated with hyperestrogenism. Previous studies have reported morphologic changes in benign and malignant prostate tissue exposed to estrogen or anti-androgens. To our knowledge, histopathologic features of prostatic adenocarcinoma in patients with cirrhosis have not been well-reported. We present a case of incidental, but pathologically significant, prostatic adenocarcinoma detected on autopsy in a 67-year-old male patient with cirrhosis and spider angiomata. The morphologic and immunohistochemical features (including variable ERG expression) of the prostatic adenocarcinoma were consistent with hormone exposure related changes, suggesting that cirrhosis-induced elevated estrogen-to-testosterone ratio and exogenous hormone therapy might induce similar phenotypes.

Comprehensive Immunophenotypic Characterization of Adult and Fetal Testes, the Excretory Duct System, and Testicular and Epididymal Appendages.

The immunophenotype of a normal testis and the excretory duct system has not been studied comprehensively in fetal and adult patients without testicular disease or hormonal manipulation so far. In addition, testicular (TA) and epididymal (EA) appendages are frequent paratesticular structures without previously reported comprehensive immunophenotypic studies. Immunohistochemistry for multiple markers, including the androgen receptor (AR), the estrogen receptor (ER), the progesterone receptor (PR), the prostate-specific antigen, the prostate-specific membrane antigen, PAX8, WT1, calretinin, CK7, CK20, OCT4, SALL4, and CD117, was performed on full sections of testicular/paratesticular tissue from a large cohort of adult and fetal autopsy patients. In contrast to adult germ cells (GC), fetal GC strongly express OCT4 and CD117, although the expression of these proteins is lost in the early postnatal period; SALL4, in contrast, is expressed in both fetal and adult GC, with only weak and focal expression in adult patients. Fetal Sertoli cells (SC) express WT1 and calretinin strongly and diffusely, in contrast to adult SC. Both fetal and adult excretory duct systems express CK7 and PAX8 with frequent AR coexpression, and all 3 main segments of the excretory duct system (ductuli efferentes, epididymis, and vas deferens) have unique immunophenotypes. The rete testis also has a unique immunohistochemical expression pattern, which includes strong expression of CK7, PAX8, WT1, calretinin, and AR. Finally, of the adult autopsy patients examined, 80% had a TA, and 60% had an EA; these paratesticular structures occurred at stereotypical locations, demonstrated reproducible morphologic features, and had a unique immunophenotype relative to other studied structures, with strong CK7, PAX8, WT1, AR, ER, and PR coexpression. The testis and the paratestis may be involved by diverse neoplastic and non-neoplastic processes, and knowledge of the immunophenotypic expression spectrum of these tissues may aid in clinical diagnosis and advance our understanding of the pathogenesis of both oncologic and nononcologic disease processes.

Whole-Exome Sequencing Reveals Mutations in Genes Linked to Hemophagocytic Lymphohistiocytosis and Macrophage Activation Syndrome in Fatal Cases of H1N1 Influenza.

BACKGROUND: Severe H1N1 influenza can be lethal in otherwise healthy individuals and can have features of reactive hemophagocytic lymphohistiocytosis (HLH). HLH is associated with mutations in lymphocyte cytolytic pathway genes, which have not been previously explored in H1N1 influenza. METHODS: Sixteen cases of fatal influenza A(H1N1) infection, 81% with histopathologic hemophagocytosis, were identified and analyzed for clinical and laboratory features of HLH, using modified HLH-2004 and macrophage activation syndrome (MAS) criteria. Fourteen specimens were subject to whole-exome sequencing. Sequence alignment and variant filtering detected HLH gene mutations and potential disease-causing variants. Cytolytic function of the PRF1 p.A91V mutation was tested in lentiviral-transduced NK-92 natural killer (NK) cells. RESULTS: Despite several lacking variables, cases of influenza A(H1N1) infection met 44% and 81% of modified HLH-2004 and MAS criteria, respectively. Five subjects (36%) carried one of 3 heterozygous LYST mutations, 2 of whom also possessed the p.A91V PRF1 mutation, which was shown to decrease NK cell cytolytic function. Several patients also carried rare variants in other genes previously observed in MAS. CONCLUSIONS: This cohort of fatal influenza A(H1N1) infections confirms the presence of hemophagocytosis and HLH pathology. Moreover, the high percentage of HLH gene mutations suggests they are risk factors for mortality among individuals with influenza A(H1N1) infection.

Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma presenting as retroperitoneal fibrosis.

Retroperitoneal fibrosis is a rare fibroinflammatory condition involving the abdominal aorta, iliac vessels, and ureters that carries an association with several other autoimmune conditions. Most cases of retroperitoneal fibrosis are thought to be idiopathic. The disorder can affect all age groups but is most common in persons between the ages of 50 and 70 years. A subset of cases is associated with an underlying immunohematologic abnormality including lymphoma. We describe in this case report a highly unusual presentation of a young woman who died with a diagnosis of "idiopathic retroperitoneal fibrosis" based on multiple biopsy procedures. Postmortem examination, however, revealed disseminated anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. The clinical and histopathologic importance of this very unusual presentation of anaplastic lymphoma kinase-positive anaplastic large cell lymphoma with retroperitoneal fibrosis is discussed.

Neck and scleral hemorrhage in drowning.

The determination of the cause and manner of death for a body recovered from the water can be difficult because of a lack of autopsy findings specific for drowning. This case report describes a 30-year-old man found submerged at the bottom of a hotel pool. An autopsy revealed scleral hemorrhages and fascial hemorrhages of multiple muscles of the anterior and posterior neck bilaterally. No evidence of traumatic injury was on the surface of the body. An investigation by law enforcement found no evidence of foul play. The occurrence of petechial and neck hemorrhage in a body recovered from the water is controversial, and a review of this literature will be given. We suggest that fascial hemorrhages of the muscles of the neck, as well as cephalic hemorrhages, can be explained by drowning-related elevated central venous pressure that is communicated to the head through the valveless veins of the neck.

Autopsy findings in eight patients with fatal H1N1 influenza.

A novel H1N1 influenza A virus emerged in April 2009, and rapidly reached pandemic proportions. We report a retrospective observational case study of pathologic findings in 8 patients with fatal novel H1N1 infection at the University of Michigan Health Systems (Ann Arbor) compared with 8 age-, sex-, body mass index-, and treatment-matched control subjects. Diffuse alveolar damage (DAD) in acute and organizing phases affected all patients with influenza and was accompanied by acute bronchopneumonia in 6 patients. Organizing DAD with established fibrosis was present in 1 patient with preexisting granulomatous lung disease. Only 50% of control subjects had DAD. Peripheral pulmonary vascular thrombosis occurred in 5 of 8 patients with influenza and 3 of 8 control subjects. Cytophagocytosis was seen in all influenza-related cases. The autopsy findings in our patients with novel H1N1 influenza resemble other influenza virus infections with the exception of prominent thrombosis and hemophagocytosis. The possibility of hemophagocytic syndrome should be investigated in severely ill patients with H1N1 infection.

Pharmacogenomics as molecular autopsy for forensic toxicology: genotyping cytochrome P450 3A4*1B and 3A5*3 for 25 fentanyl cases.

Pharmacogenomics, the study on genetic contributions to drug action may help in certifying fentanyl toxicity. Fentanyl is used clinically as an adjunct to surgical anesthesia and for chronic pain management. Its toxicity may be partially due to cytochrome P450 (CYP) 3A4*1B and 3A5*3 variant alleles, resulting in variable fentanyl metabolism. In this study, we examined 25 fentanyl-related deaths (22 Caucasians, 1 African-American, and 2 Native-Americans) from the Milwaukee County Medical Examiner's Office and referral cases. Fentanyl and norfentanyl in postmortem blood samples were analyzed by radioimmunoassay and liquid chromatography-mass spectrometry-mass spectrometry. The samples were then genotyped for CYP3A4*1B and 3A5*3 using Pyrosequencing. Genotyping showed: 1 CYP3A4*1B homozygous and CYP3A5*3 heterozygous, 1 compound CYP3A4*1B and CYP3A5*3 heterozygous, 22 CYP3A4*1B wild type and CYP3A5*3 homozygous, and 1 CYP3A5*3 and CYP3A4*1B wild type. CYP variant allelic frequencies of the 25 cases were 6% for CYP3A4*1B and 92% for CYP3A5*3, compared with normal Caucasian CYP3A4*1B, 3-8%, and CYP3A5*3, 85-95%. The mean fentanyl concentration and metabolic ratio of fentanyl to norfentanyl of the 2 cases with CYP3A4*1B and CYP3A5*3 variants were 12.8 and 1.4 microg/L, respectively, lower than those of 22 cases with wild type CYP3A4*1B and CYP3A5*3 homozygous variants, 16.7 and 7.3 microg/L, respectively. The postmortem/in vivo data provided the first scientific evidence that CYP3A5 is involved in the fentanyl metabolism, and homozygous CYP3A5 *3 causes impaired metabolism of fentanyl, and genotyping CYP3A4*1B and 3A5*3 variants may help to certify the fentanyl toxicity.

Esophageal and pharyngeal injuries associated with the use of the esophageal-tracheal Combitube.

The Combitube is a ventilatory device consisting of a twin lumen tube with proximal and distal inflatable cuffs. The major benefit of the Combitube is that its design and function allow for ventilation through non-laryngoscope-assisted insertion into either the trachea, or esophagus. As with any invasive procedure, intubation using the Combitube carries certain risks and potential complications. The majority of complications are relatively minor; however, a rare and serious complication reported primarily in the anesthesiology literature is laceration of the esophagus. This reportedly rare injury is increasingly seen by medical examiners/coroners in the forensic setting. This paper presents a series of three cases of esophageal laceration and a single case of perforation of the hypopharynx associated with the use of the Combitube, while also exploring potential mechanisms of injury. In addition, this work demonstrates the vital role the medical examiner/coroner plays in identifying existing or potential problems with current or emerging medical devices.

Criteria for the interpretation of cocaine levels in human biological samples and their relation to the cause of death.

The determination that cocaine is directly responsible for the immediate cause of death should be considered only when there is a reasonably complete understanding of the circumstances or facts surrounding the death. Another, more obvious and immediate cause of death must be absent, or, at least cocaine must be shown to be a significant contributing factor in the chain of medical findings that lead directly to the immediate cause of death. Not all death investigation requires the sequential steps described in this paper, but these steps must be considered early on in the investigation whenever there is scene, investigational, medical or a historical basis to believe that cocaine is directly related to the cause of death. A relatively high profile death when cocaine is known to be involved, or a death involving unusual behavior on the part of the deceased with police involvement are examples where these considerations may well apply. Information needs to be obtained as soon as possible to have the highest chance of successfully documenting the toxicologic basis for the diagnosis. These facts would include, but would not necessarily be limited to, a scene investigation (whenever possible), a careful review of the investigative reports from all involved agencies, the initial core temperature of the body as well as that of the environment at the time of the collapse or death, the past medical history of the individual, and the results of a complete forensic autopsy and toxicologic studies. Knowledge of and an understanding of the current relevant forensic literature on this subject should be available to the reviewer prior to any interpretation of the significance of cocaine upon a specific death.

National Association of Medical Examiners position paper on the certification of cocaine-related deaths.

The National Association of Medical Examiners Committee on Cocaine-related Deaths recommends that the following guidelines be applied in the process of documenting, interpreting, and certifying potential cocaine-related fatalities. The committee cautions that the investigation of any drug-related death requires a complete investigation of the circumstances of death, the death scene, and past medical history. It is also necessary to have the results of the forensic toxicological analysis and those of a complete forensic autopsy examination prior to formulating an opinion as to the cause and manner of death. Cocaine should be considered the underlying cause of the death when 1 or more of the following is true: (1). the circumstances surrounding the death can be associated with an acute cocaine exposure and there are no supervening causes of death; (2). the immediate cause of death is directly due to a readily identifiable mechanism or disease such as a gunshot wound or a stroke, yet the acute use of cocaine was the direct underlying cause of the trauma or the disease process; and (3). chronic cocaine use leads to a disease that results in an ultimately fatal pathologic process leading to organ injury and death. The committee further cautions that reported drug levels may not directly relate to the toxic or lethal effects of the drug upon the patient. These guidelines are intended for use by practicing medical examiners and physicians who certify drug deaths, as well as providing education tools for students.

Pharmacogenomics as an aspect of molecular autopsy for forensic pathology/toxicology: does genotyping CYP 2D6 serve as an adjunct for certifying methadone toxicity?

Pharmacogenomics, applied as an aspect of molecular autopsy, may be used as an adjunct for certifying methadone fatalities. Methadone is metabolized by cytochrome P-450 (CYP) 1A2, 3A4, and 2D6. We hypothesized that methadone toxicity may be partially due to CYP 2D6 *3, *4, and *5 variant alleles, resulting in poor drug metabolism. A retrospective analysis was performed on covariables and risk factors of 21 methadone cases from the Milwaukee County Medical Examiner's Office (1998-2000). PCR genotyping showed: one heterozygous for 2D6*3, two homozygous for 2D6*4, five heterozygous for 2D6*4, and one heterozygous for both 2D6*3 and *4. This limited number of cases showed that the prevalence of poor metabolizer was higher but not significantly different from that of a control group (n = 23) (P > 0.05, Fisher Exact Test). Thus, CYP 2D6 mutations may not yet be directly associated with methadone toxicity. However, pharmacogenomics, complementing other case findings, served as an adjunct in interpreting methadone toxicity of poor and intermediate metabolizers.

Pharmacogenomics as molecular autopsy for postmortem forensic toxicology: genotyping cytochrome P450 2D6 for oxycodone cases.

Pharmacogenomics, the study of the impact of heritable traits on pharmacology and toxicology, may serve as an adjunct for certifying opioid fatalities. Oxycodone, frequently prescribed for the relief of moderate to severe pain, is metabolized by cytochrome P450 (CYP) 2D6, encoded by a polymorphic gene with three mutations (*3, *4, and *5) with a combined 95% allelic frequency and about 10% prevalence. Individuals with variant alleles are more susceptible to oxycodone toxicity. By assessing the prevalence of CYP2D6 polymorphisms and covariables, we hypothesized that oxycodone fatality may be partially due to poor drug metabolism caused by CYP2D6 variant alleles. From the Milwaukee County Medical Examiner's Office (MCMEO), a retrospective analysis of 15 oxycodone cases was followed by genotyping blood samples for the variant alleles by conventional and real-time PCRs. Institutional Review Board approval was obtained. Oxycodone, extracted from blood and/or urine, was quantitated by GC-MS. The results show two homozygous for 2D6*4 and four heterozygous for 2D6*4. The MCMEO was not significantly different from those in the control group (n = 26) (p > 0.05, Fisher's Exact Test). However, genotyping CYP2D6 provided a more definitive interpretation of the oxycodone toxicity in four cases. Therefore, pharmacogenomics may serve as an adjunct in the determination of the cause and manner of death in forensic toxicology and a pharmacogenomic algorithm for genotyping has been proposed.