COVID-19 in a Hispanic Woman

Public perspectives on healthcare professional-directed communication of hereditary genetic risks: a mixed-method systematic review

Genetic testing has revolutionized the identification of individuals at increased risk for various hereditary conditions, enabling early intervention and preventive measures. However, effective cascade counseling and testing depends on successful intra-familial communication. This mixed-method systematic review aimed to explore the general population's perspectives and preferences regarding the communication of potential genetic risk information by healthcare professionals. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered in the International Prospective Register of Systematic Reviews database (CRD42024532829). A comprehensive search of six databases yielded 17,292 records. After removing duplicates and screening for relevance, nine studies were included in the final analysis, conducted across diverse Western countries using both qualitative and quantitative designs. Results indicated a preference for healthcare-mediated communication, particularly through formal methods as letters, valued for their clarity and reliability. The role of family-mediated communication is nuanced, influenced by interpersonal relationship quality and the emotional burden of disclosing sensitive information. Ethical and legal considerations highlighted public support for overriding confidentiality in treatable conditions, while emphasizing respect for individual privacy and autonomy in untreatable conditions. This review underscores the importance of understanding public preferences to develop tailored communication strategies that balance professional involvement with respect for individual and familial dynamics. Healthcare professionals should be trained to provide empathetic, clear, and accurate information, considering the specific needs and contexts of at-risk individuals.

Preventing Type 2 Diabetes after Gestational Diabetes: A Systematic Review Mapping Physical Activity Components using the Socio-Ecological Model

OBJECTIVES

Gestational diabetes commonly occurs during pregnancy and increases lifetime risk of type 2 diabetes following pregnancy. Engaging in physical activity postnatally can reduce this subsequent risk. Interventions aiming to increase physical activity after gestational diabetes may not address the wide range of post-pregnancy barriers. A socio-ecological approach highlights the need to include multi-level factors such as social, community and organisational factors. The aim of the review was to map intervention components to prevent type 2 diabetes after gestational diabetes using the socio-ecological model as a framework and investigate how physical activity changes align with different intervention components utilised.

METHODS

Eligible studies included any study type within 5 years of a gestational diabetes diagnosis and targeted physical activity. A systematic search of MEDLINE, Cochrane Library, Web of Science, CINAHL Complete, and Scopus was conducted in October 2022. Results were categorised based on whether findings demonstrated no increases, non-statistically significant increases or statistically significant increases in physical activity.

RESULTS

Forty-eight studies were included (37 different interventions). Thirty-eight studies were assessed as "adequate" quality, only two studies were "good" quality, and the remaining were limited quality. Mixed physical activity outcomes were observed across components used at the intrapersonal level, with components across other levels of the socio-ecological model showing more increases in physical activity. Intervention components within the social and organisational levels, for example childcare provision, providing group-based sessions and offering remote delivery, were more often present in interventions with physical activity increases.

CONCLUSIONS FOR PRACTICE

Future interventions targeting physical activity after gestational diabetes should aim to include social and organisational-level components in their intervention design. This systematic review was registered in PROSPERO (ID: CRD42021272044).

Fulminant Myocarditis with SARS-CoV-2 Infection: A Narrative Review from the Case Studies

One of the severe complications of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is myocarditis. However, the characteristics of fulminant myocarditis with SARS-CoV-2 infection are still unclear. We systematically reviewed the previously reported cases of fulminant myocarditis associated with SARS-CoV-2 infection from January 2020 to December 2022, identifying 108 cases. Of those, 67 were male and 41 female. The average age was 34.8 years; 30 patients (27.8%) were ≤20 years old, whereas 10 (9.3%) were ≥60. Major comorbidities included hypertension, obesity, diabetes mellitus, asthma, heart disease, gynecologic disease, hyperlipidemia, and connective tissue disorders. Regarding left ventricular ejection fraction (LVEF) at admission, 93% of the patients with fulminant myocarditis were classified as having heart failure with reduced ejection fraction (LVEF ≤ 40%). Most of the cases were administered catecholamines (97.8%), and mechanical circulatory support (MCS) was required in 67 cases (62.0%). The type of MCS was extracorporeal membrane oxygenation (n = 56, 83.6%), percutaneous ventricular assist device (Impella®) (n = 19, 28.4%), intra-aortic balloon pumping (n = 12, 12.9%), or right ventricular assist device (n = 2, 3.0%); combination of these devices occurred in 20 cases (29.9%). The average duration of MCS was 7.7 ± 3.8 days. Of the 76 surviving patients whose cardiac function was available for follow-up, 65 (85.5%) recovered normally. The overall mortality rate was 22.4%, and the recovery rate was 77.6% (alive: 83 patients, dead: 24 patients; outcome not described: 1 patient).

What can autopsy say about COVID-19? A case series of 60 autopsies

INTRODUCTION

Autopsies in SARS-CoV-2 infected cadavers are mainly performed to distinguish patients who died with SARS-CoV-2 infection from those who died of COVID-19. The aim of the current study is to assess the most frequent autopsy findings in patients who died of COVID-19 and to establish an association with clinical records.

MATERIALS AND METHODS

60 patients died between April 2020 and March 2021 after SARS-CoV-2 infection underwent a full autopsy performed at Fondazione Policlinico Universitario Agostino Gemelli IRCCS (Rome). Ante-mortem diagnosis of SARS-CoV-2 infection was microbiologically confirmed.

RESULTS

55 (92%) of cases had at least a comorbidity. At microscopic examination, 40 (67%) of the patients presented pulmonary intravascular coagulation with an inflammatory pattern. Pulmonary microangiopathy was a rare finding (n = 8; 13%). Myocardiosclerosis was the main heart finding (n = 44; 73%). Liver involvement with congestion and hypotrophy was found in 33 (55%) of cadavers. Renal tubular epithelial exfoliation (n = 12; 20%) and intravascular coagulation (n = 4; 7%) were frequent observations. During hospitalization 31% of patients (n = 19) developed acute kidney injury (AKI).

CONCLUSIONS

Lungs and kidneys have been shown to play a pivotal role in COVID-19. The gradual worsening of renal function and AKI might be the result of the progressive collapse of cardiopulmonary system.

A Review on Locomotion Mode Recognition and Prediction When Using Active Orthoses and Exoskeletons

Understanding how to seamlessly adapt the assistance of lower-limb wearable assistive devices (active orthosis (AOs) and exoskeletons) to human locomotion modes (LMs) is challenging. Several algorithms and sensors have been explored to recognize and predict the users' LMs. Nevertheless, it is not yet clear which are the most used and effective sensor and classifier configurations in AOs/exoskeletons and how these devices' control is adapted according to the decoded LMs. To explore these aspects, we performed a systematic review by electronic search in Scopus and Web of Science databases, including published studies from 1 January 2010 to 31 August 2022. Sixteen studies were included and scored with 84.7 ± 8.7% quality. Decoding focused on level-ground walking along with ascent/descent stairs tasks performed by healthy subjects. Time-domain raw data from inertial measurement unit sensors were the most used data. Different classifiers were employed considering the LMs to decode (accuracy above 90% for all tasks). Five studies have adapted the assistance of AOs/exoskeletons attending to the decoded LM, in which only one study predicted the new LM before its occurrence. Future research is encouraged to develop decoding tools considering data from people with lower-limb impairments walking at self-selected speeds while performing daily LMs with AOs/exoskeletons.

Findings and inferences from full autopsies, minimally invasive autopsies and biopsy studies in patients who died as a result of COVID19 - A systematic review

Many articles on COVID19 deaths have been published since the pandemic has occurred. On reviewing the articles published until June 2021, the findings were very heterogeneous. Adding to the existing knowledge, there were also some unique observations made in the pathogenesis of COVID19. This review was done to determine the findings obtained and inferences drawn from various studies published globally among patients who died due to COVID19. PRISMA guidelines were used to conduct this systematic review. A search of databases like PubMed, ScienceDirect and Epistemonikos was done. The articles focusing on postmortem sample studies involving full autopsies, minimally invasive autopsies and tissue biopsy studies were screened and searched. The studies included were all the case reports, case series, narrative reviews and systematic reviews obtained in full text and in the English language containing study information, and samples obtained postmortem. The information obtained was tabulated using Microsoft excel sheets. The duplicates were removed at the beginning of the tabulation. Zotero referencing software was used for article sorting and citation and bibliography. Two authors independently reviewed the articles throughout the process to prevent bias. Adding to the heterogeneity of COVID19, the concept of lethality in preexisting disease conditions, the occurrence of secondary bacterial and fungal infections, and other pathogenetic mechanisms uniquely encountered are to be considered in treating the patients. Also, the presence of SARS-CoV-2 postmortem is established and should be considered a hazard.

The Epidemiology of Bovine Viral Diarrhea Virus in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

Introduction

Bovine viral diarrhea virus (BVDV) causes reproductive inefficiencies and negatively impacts the economy of low- and middle-income countries (LMICs). It is characterized by a combination of syndromes that result in poor production performance and calf morbidity and mortality. BVDV control is possible by introduction of biosecurity measures, test-and-cull, and vaccination programs as accomplished in high-income countries. Knowledge of BVDV epidemiology is limited in many LMICs, which hinders implementation of effective control programs. We carried out a systematic review and meta-analysis to estimate the burden of BVDV, identify risk factors related to its occurrence, and health and economic impacts on production systems.

Materials and Methods

Relevant BVD articles were collated from library databases; 690 abstracts and full texts were found in an initial search followed by filtering of 59 manuscripts. We accounted for quality and risk of bias in the meta-analysis. Prevalence, exposure, and current infection at regional, production, and farming system levels were estimated using logistic random-effects meta-regression models. Finally, we calculated the proportion of studies that addressed risk factors and health and economic impacts across different production systems to inform future preventative strategies in LMICs.

Results

Seroprevalence was high and varied between regions. Mean weighted prevalence was 39.5% (95% CI 25-56.1), 45.2% (95% CI 35.9-54.8), 49.9% (95% CI 25.5-74.3), and 21.6% (95% CI 0.5-56) for sub-Saharan Africa, South America, Middle East, and Asia, respectively. Seroprevalence varied across farming systems, with smallholder farming showing the highest values. Herdsize was the most frequently reported risk factor, and the percentage of articles that reported herdsize as a risk factor were 20.6%, 33.3%, and 38.4% for dairy, beef and mixed systems respectively. Abortion (13.7% of articles) was the main reported health impact in dairy systems. Some articles reported milk drop (4.6% of articles), but no article investigated the economic cost of BVDV in farming systems.

Conclusion

Animal-level seroprevalence varied across all regions. Most of the studies focused on BVDV seroprevalence. There were some articles that investigated risk factors and health impacts, and there were even less that investigated economic impacts. Future studies should focus on identifying risk factors and quantifying health and economic impacts across systems. Understanding these aspects is crucial to develop management strategies to apply across diverse production systems in LMICs.

A Young Lady With Myopericarditis: An Unusual Presentation of COVID-19 Infection

Fever, sore throat, cough, and shortness of breath are the characteristic clinical manifestations of coronavirus disease 2019 (COVID-19). As the epidemic spreads, it is evident that the infection can affect not only the lungs but also other organs. By attaching to the angiotensin-converting enzyme-2 receptor (ACE-2), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces lung injury. SARS-CoV-2 can also cause damage to the heart and blood vessels as these organs have abundant ACE-2 receptors. Here, we present a 28-year-old lady with shortness of breath, chest pain, low blood pressure, and a pulse rate that fluctuates widely. She had SARS-CoV-2-induced myopericarditis after further testing. Initially, we treated her with high-dose prednisolone and other supportive medications. Then, we also added colchicine and ibuprofen due to the initial poor response, and the result was satisfying after two weeks of treatment.

Cytopathological Findings in Bronchoalveolar Lavage from Patients with COVID-19

Information on cellular analysis of bronchoalveolar lavage (BAL) in patients with COVID-19 is limited. Some studies have described an increase in lymphocyte percentage or exuberant plasmacytosis. Some reports addressed the importance of molecular testing on BAL samples to confirm COVID-19 pneumonia, in clinically highly suspected patients with consecutive negative nasopharyngeal swab results. In addition to atypical lymphocytes in the peripheral blood, morphologic findings of atypical lymphocytes in BAL were also reported in a few patients. The objective of this study was to describe the cytopathic characteristics identified, any data presented here are descriptives and intended to trigger further research. Three general aspects have been evaluated in each sample: reactive changes, virus-related pathological changes, and differential leukocyte count. Seventeen samples were collected. All samples were negative for malignancy, with an inflammatory background, predominantly lymphohistiocytic in 5 samples, histiocytic in 9, and 3 with predominantly neutrophilic. Hemosiderin-laden macrophages were observed in 12/17. Nonspecific reactive cell changes were identified in 4 samples, including bronchial, alveolar, and reserve cell hyperplasia. Virus-related pathological changes were observed in 14 samples, such as loss of nuclear chromatin pattern, lymphocytes with atypical nuclei, nuclear and cytoplasmic inclusions, multinucleations in bronchial cells and macrophages, or multinucleated giant cells. The identification of multinucleated giant cells could represent a cytopathic effect induced by the virus, at the same time the nuclear clearance of pneumocytes as a possible direct effect. BAL is a procedure aimed at obtaining cells from the respiratory tract that can provide valuable and rapid information. It is important to collect and describe as many cytopathological findings as possible, which can provide relevant information for future studies.

Comorbidities and autopsy findings of COVID-19 deaths and their association with time to death: a systematic review and meta-analysis

OBJECTIVE

Examination of postmortem findings can help establish effective therapeutic strategies to reduce mortality. The aim of this study was therefore to review complete autopsy cases and their postmortem findings and comorbidities associated with death caused by COVID-19, in order to establish a profile of the deceased and the likelihood of time to death.

METHODS

A systematic review was carried out following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and meets Cochrane criteria recommendations (PROSPERO registration number CRD 42020209649). An electronic search in the databases Pubmed, Scopus, Web of Science, Wiley Online Library, and Scientific Electronic Library Online (SciELO) was performed.

RESULTS

The search strategy yielded a total of 25 articles where 140 cases of complete autopsies were reported. The most prevalent comorbidity was vascular diseases. Patients with vascular disease, heart disease, and diabetes died significantly in a shorter period of time. Autopsies mainly focused on the lungs. The proliferative phase of Diffuse Alveolar Damage (DAD) was the most reported in the microscopic postmortem findings, and these patients died in a shorter period of time. However, individuals aged over 80 years significantly presented fibrotic phase of DAD at the time of death. The kidney was the second most affected organ with thrombosis and tubular damage, followed by the liver with congestion and necrosis.

CONCLUSION

Given that accurate information of complete autopsies findings is still scarce, it is necessary to perform complete autopsies by examining organs other than the lungs in order to provide information to improve new treatment strategies in patients with a high risk of mortality.

Cytokine storm and histopathological findings in 60 cases of COVID-19-related death: from viral load research to immunohistochemical quantification of major players IL-1β, IL-6, IL-15 and TNF-α

This study involves the histological analysis of samples taken during autopsies in cases of COVID-19 related death to evaluate the inflammatory cytokine response and the tissue localization of the virus in various organs. In all the selected cases, SARS-CoV-2 RT-PCR on swabs collected from the upper (nasopharynx and oropharynx) and/or the lower respiratory (trachea and primary bronchi) tracts were positive. Tissue localization of SARS-CoV-2 was detected using antibodies against the nucleoprotein and the spike protein. Overall, we tested the hypothesis that the overexpression of proinflammatory cytokines plays an important role in the development of COVID-19-associated pneumonia by estimating the expression of multiple cytokines (IL-1β, IL-6, IL-10, IL-15, TNF-α, and MCP-1), inflammatory cells (CD4, CD8, CD20, and CD45), and fibrinogen. Immunohistochemical staining showed that endothelial cells expressed IL-1β in lung samples obtained from the COVID-19 group (p < 0.001). Similarly, alveolar capillary endothelial cells showed strong and diffuse immunoreactivity for IL-6 and IL-15 in the COVID-19 group (p < 0.001). TNF-α showed a higher immunoreactivity in the COVID-19 group than in the control group (p < 0.001). CD8 + T cells where more numerous in the lung samples obtained from the COVID-19 group (p < 0.001). Current evidence suggests that a cytokine storm is the major cause of acute respiratory distress syndrome (ARDS) and multiple organ failure and is consistently linked with fatal outcomes.

COVID-19 associated myocarditis: A systematic review

Background

Most COVID-19 infections result in a viral syndrome characterized by fever, cough, shortness of breath, and myalgias. A small but significant proportion of patients develop severe COVID-19 resulting in respiratory failure. Many of these patients also develop multi-organ dysfunction as a byproduct of their critical illness. Although heart failure can be a part of this, there also appears to be a subset of patients who have primary cardiac collapse from COVID-19.

Objective

Conduct a systematic review of COVID-19-associated myocarditis, including clinical presentation, risk factors, and prognosis.

Discussion

Our review demonstrates two distinct etiologies of primary acute heart failure in surprisingly equal incidence in patients with COVID-19: viral myocarditis and Takotsubo cardiomyopathy. COVID myocarditis, Takotsubo cardiomyopathy, and severe COVID-19 can be clinically indistinguishable. All can present with dyspnea and evidence of cardiac injury, although in myocarditis and Takotsubo this is due to primary cardiac dysfunction as compared to respiratory failure in severe COVID-19.

Conclusion

COVID-19-associated myocarditis differs from COVID-19 respiratory failure by an early shock state. However, not all heart failure from COVID-19 is from direct viral infection; some patient's develop takotsubo cardiomyopathy. Regardless of etiology, steroids may be a beneficial treatment, similar to other critically ill COVID-19 patients. Evidence of cardiac injury in the form of ECG changes or elevated troponin in patients with COVID-19 should prompt providers to consider concurrent myocarditis.

High Prevalence of Pre-Existing Liver Abnormalities Identified Via Autopsies in COVID-19: Identification of a New Silent Risk Factor?

A high prevalence of hepatic pathology (in 17 of 19 cases) was reported in post-mortem (PM) examinations of COVID-19 patients, undertaken between March 2020 and February 2021 by a single autopsy pathologist in two English Coronial jurisdictions. The patients in our cohort demonstrated high levels of recognised COVID-19 risk factors, including hypertension (8/16, 50%), type 2 diabetes mellitus (8/16, 50%) and evidence of arteriopathy 6/16 (38%). Hepatic abnormalities included steatosis (12/19; 63%), moderate to severe venous congestion (5/19; 26%) and cirrhosis (4/19; 21%). A subsequent literature review indicated a significantly increased prevalence of steatosis (49%), venous congestion (34%) and cirrhosis (9.3%) in COVID-19 PM cases, compared with a pre-pandemic PM cohort (33%, 16%, and 2.6%, respectively), likely reflecting an increased mortality risk in SARS-CoV-2 infection for patients with pre-existing liver disease. To corroborate this observation, we retrospectively analysed the admission liver function test (LFT) results of 276 consecutive, anonymised COVID-19 hospital patients in our centre, for whom outcome data were available. Of these patients, 236 (85.5%) had significantly reduced albumin levels at the time of admission to hospital, which was likely indicative of pre-existing chronic liver or renal disease. There was a strong correlation between patient outcome (length of hospital admission or death) and abnormal albumin at the time of hospital admission (p = 0.000012). We discuss potential mechanisms by which our observations of hepatic dysfunction are linked to a risk of COVID-19 mortality, speculating on the importance of recently identified anti-interferon antibodies.

Histopathological findings and clinicopathologic correlation in COVID-19: a systematic review

The severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) pandemic has had devastating effects on global health and worldwide economy. Despite an initial reluctance to perform autopsies due to concerns for aerosolization of viral particles, a large number of autopsy studies published since May 2020 have shed light on the pathophysiology of Coronavirus disease 2019 (COVID-19). This review summarizes the histopathologic findings and clinicopathologic correlations from autopsies and biopsies performed in patients with COVID-19. PubMed and Medline (EBSCO and Ovid) were queried from June 4, 2020 to September 30, 2020 and histopathologic data from autopsy and biopsy studies were collected based on 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 58 studies reporting 662 patients were included. Demographic data, comorbidities at presentation, histopathologic findings, and virus detection strategies by organ system were collected. Diffuse alveolar damage, thromboembolism, and nonspecific shock injury in multiple organs were the main findings in this review. The pathologic findings emerging from autopsy and biopsy studies reviewed herein suggest that in addition to a direct viral effect in some organs, a unifying pathogenic mechanism for COVID-19 is ARDS with its known and characteristic inflammatory response, cytokine release, fever, inflammation, and generalized endothelial disturbance. This study supports the notion that autopsy studies are of utmost importance to our understanding of disease features and treatment effect to increase our knowledge of COVID-19 pathophysiology and contribute to more effective treatment strategies.

Translational deep phenotyping of deaths related to the COVID-19 pandemic: protocol for a prospective observational autopsy study

INTRODUCTION

The COVID-19 pandemic is an international emergency with an extreme socioeconomic impact and a high mortality and disease burden. The COVID-19 outbreak is neither fully understood nor fully pictured. Autopsy studies can help understand the pathogenesis of COVID-19 and has already resulted in better treatment of patients. Structured and systematic autopsy of COVID-19-related deaths will enhance the mapping of pathophysiological pathways, not possible in the living. Furthermore, it provides an opportunity to envision factors translationally for the purpose of disease prevention in this and future pandemics. This is the protocol for an autopsy study that offers an umbrella for deep and diverse investigations of COVID-19-related deaths, including a systematic investigation of 'long' COVID-19 by means of extensive and systematic tissue sampling.

METHODS AND ANALYSIS

A COVID-19-specific autopsy algorithm has been created to cover all cases undergoing clinical or forensic autopsy in Denmark. The algorithm describes advanced tissue sampling and a translational analytical follow-up for deep phenotyping. The translational approach covers registry data, postmortem imaging, gross autopsy findings, microscopic organ changes, postmortem toxicology, postmortem biochemical investigation, microbiological profiling and immunological status at the time of death, and future research projects covering genetics and epigenetics on an organ level.

ETHICS AND DISSEMINATION

This study has been approved by the Regional Ethics Committee of the Region of Greater Copenhagen (No: H-20078436) and the Danish Data Protection Agency (No: 2002-54-1080). Next of kin gave informed consent to research. The study results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

This study is purely observational and, as such, does not meet the criteria of the International Committee of Medical Journal Editors for clinical trials; thus, there is no need for registration in a database of research trials, such as clinical trials. To facilitate cooperation in research, provide transparency on case recruitment for publications to come and to avoid unnecessary duplicate work, we nevertheless wish to publish our protocol.

Viral Load and Patterns of SARS-CoV-2 Dissemination to the Lungs, Mediastinal Lymph Nodes, and Spleen of Patients with COVID-19 Associated Lymphopenia

Lymphopenia is a frequent hematological manifestation, associated with a severe course of COVID-19, with an insufficiently understood pathogenesis. We present molecular genetic immunohistochemical, and electron microscopic data on SARS-CoV-2 dissemination and viral load (VL) in lungs, mediastinum lymph nodes, and the spleen of 36 patients who died from COVID-19. Lymphopenia <1 × 109/L was observed in 23 of 36 (63.8%) patients. In 12 of 36 cases (33%) SARS-CoV-2 was found in lung tissues only with a median VL of 239 copies (range 18-1952) SARS-CoV-2 cDNA per 100 copies of ABL1. Histomorphological changes corresponding to bronchopneumonia and the proliferative phase of DAD were observed in these cases. SARS-CoV-2 dissemination into the lungs, lymph nodes, and spleen was detected in 23 of 36 patients (58.4%) and was associated with the exudative phase of DAD in most of these cases. The median VL in the lungs was 12,116 copies (range 810-250281), lymph nodes-832 copies (range 96-11586), and spleen-71.5 copies (range 0-2899). SARS-CoV-2 in all cases belonged to the 19A strain. A immunohistochemical study revealed SARS-CoV-2 proteins in pneumocytes, alveolar macrophages, and bronchiolar epithelial cells in lung tissue, sinus histiocytes of lymph nodes, as well as cells of the Billroth pulp cords and spleen capsule. SARS-CoV-2 particles were detected by transmission electron microscopy in the cytoplasm of the endothelial cell, macrophages, and lymphocytes. The infection of lymphocytes with SARS-CoV-2 that we discovered for the first time may indicate a possible link between lymphopenia and SARS-CoV-2-mediated cytotoxic effect.

Pathological diagnosis of Coronavirus-related nephropathy: insight from postmortem studies

A novel coronavirus pneumonia first occurred in Wuhan, China in early December 2019; the causative agent was identified and named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the World Health Organization (WHO), and the resulting disease termed coronavirus disease 2019 (COVID-19), according to the WHO coronavirus disease situation reports. This condition has spread rapidly all over the world and caused more than 125 million cases globally, with more than 2 million related deaths. Two previous outbreaks due to zoonotic coronaviruses have occurred in the last 20 years, namely the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), causing high morbidity and mortality in human populations upon crossing the species barriers. SARS-CoV-2, SARS-CoV, and MERS-CoV show several similarities in pathogenicity and clinical presentations, the latter ranging from asymptomatic infection to severe acute respiratory distress syndrome (ARDS) and multiorgan impairment. Acute kidney injury (AKI) has been commonly reported in patients with CoV infections; therefore, pathological analysis of renal parenchyma in these patients has been carried out in order to improve knowledge about underlying mechanisms. Viral infection has been demonstrated in the renal tubular epithelial cells by electron microscopy (EM), immunohistochemistry (IHC), and in situ hybridization (ISH), although with conflicting results. Light microscopy (LM) changes have been described in the renal parenchyma primarily in the form of acute renal tubular damage, possibly due to direct viral cytopathic effect and immune-mediated mechanisms such as cytokine storm syndrome. In this review, we describe and discuss the spectrum of histological, ultrastructural, and molecular findings in SARS-CoV, MERS-CoV, and SARS-CoV-2-related renal pathology obtained from postmortem studies, as well as intrinsic limitations and pitfalls of current diagnostic techniques.

Autopsy findings in COVID-19-related deaths: a literature review

Although many clinical reports have been published, little is known about the pathological post-mortem findings from people who have died of the novel coronavirus disease. The need for postmortem information is urgent to improve patient management of mild and severe illness, and treatment strategies. The present systematic review was carried out according to the Preferred Reporting Items for Systematic Review (PRISMA) standards. A systematic literature search and a critical review of the collected studies were conducted. An electronic search of PubMed, Science Direct Scopus, Google Scholar, and Excerpta Medica Database (EMBASE) from database inception to June 2020 was performed. We found 28 scientific papers; the total amount of cases is 341. The major histological feature in the lung is diffuse alveolar damage with hyaline membrane formation, alongside microthrombi in small pulmonary vessels. It appears that there is a high incidence of deep vein thrombosis and pulmonary embolism among COVID-19 decedents, suggesting endothelial involvement, but more studies are needed. A uniform COVID-19 post-mortem diagnostic protocol has not yet been developed. In a time in which international collaboration is essential, standardized diagnostic criteria are fundamental requirements.

Implications of microscale lung damage for COVID-19 pulmonary ventilation dynamics: A narrative review

The COVID-19 pandemic surges on as vast research is produced to study the novel SARS-CoV-2 virus and the disease state it induces. Still, little is known about the impact of COVID-19-induced microscale damage in the lung on global lung dynamics. This review summarizes the key histological features of SARS-CoV-2 infected alveoli and links the findings to structural tissue changes and surfactant dysfunction affecting tissue mechanical behavior similar to changes seen in other lung injury. Along with typical findings of diffuse alveolar damage affecting the interstitium of the alveolar walls and blood-gas barrier in the alveolar airspace, COVID-19 can cause extensive microangiopathy in alveolar capillaries that further contribute to mechanical changes in the tissues and may differentiate it from previously studied infectious lung injury. Understanding microlevel damage impact on tissue mechanics allows for better understanding of macroscale respiratory dynamics. Knowledge gained from studies into the relationship between microscale and macroscale lung mechanics can allow for optimized treatments to improve patient outcomes in case of COVID-19 and future respiratory-spread pandemics.

Lung histopathological findings in COVID-19 disease - a systematic review

Since December 2019, the global burden of the COVID-19 pandemic has increased rapidly and has impacted nearly every country in the world, affecting those who are elderly or with underlying comorbidities or immunocompromised states. Aim of this systematic review is to summarize lung histopathological characteristics of COVID-19, not only for diagnostic purpose but also to evaluate changes that can reflect pathophysiological pathways that can inform clinicians of useful treatment strategies. We identified following histopathological changes among our patients:: hyaline membranes; endothelial cells/ interstitial cells involvement; alveolar cells, type I pneumocytes/ type II pneumocytes involvement; interstitial and/ or alveolar edema; evidence of hemorrhage, of inflammatory cells, evidence of microthrombi; evidence of fibrin deposition and of viral infection in the tissue samples.The scenario with proliferative cell desquamation is typical of Acute Respiratory Distress Syndrome (ARDS) that can be classified as diffuse alveolar damage (DAD) and not DAD-ARDS. The proposed pathological mechanism concerns the role of both innate and adaptive components of the immune system. COVID-19 lethal cases present themselves as a heterogeneous disease, characterized by the different simultaneous presence of different histological findings, which reflect histological phases with corresponding different pathological pathways (epithelial, vascular and fibrotic changes), in the same patient.

A series of COVID-19 autopsies with clinical and pathologic comparisons to both seasonal and pandemic influenza

Autopsies of patients who have died from COVID‐19 have been crucial in delineating patterns of injury associated with SARS‐CoV‐2 infection. Despite their utility, comprehensive autopsy studies are somewhat lacking relative to the global burden of disease, and very few comprehensive studies contextualize the findings to other fatal viral infections. We developed a novel autopsy protocol in order to perform postmortem examinations on victims of COVID‐19 and herein describe detailed clinical information, gross findings, and histologic features observed in the first 16 complete COVID‐19 autopsies. We also critically evaluated the role of ancillary studies used to establish a diagnosis of COVID‐19 at autopsy, including immunohistochemistry (IHC), in situ hybridization (ISH), and electron microscopy (EM). IHC and ISH targeting SARS‐CoV‐2 were comparable in terms of the location and number of infected cells in lung tissue; however, nonspecific staining of bacteria was seen occasionally with IHC. EM was unrevealing in blindly sampled tissues. We then compared the clinical and histologic features present in this series to six archival cases of fatal seasonal influenza and six archival cases of pandemic influenza from the fourth wave of the ‘Spanish Flu’ in the winter of 1920. In addition to routine histology, the inflammatory infiltrates in the lungs of COVID‐19 and seasonal influenza victims were compared using quantitative IHC. Our results demonstrate that the clinical and histologic features of COVID‐19 are similar to those seen in fatal cases of influenza, and the two diseases tend to overlap histologically. There was no significant difference in the composition of the inflammatory infiltrate in COVID‐19 and influenza at sites of acute lung injury at the time of autopsy. Our study underscores the relatively nonspecific clinical features and pathologic changes shared between severe cases of COVID‐19 and influenza, while also providing important caveats to ancillary methods of viral detection.

Postmortem Findings Associated With SARS-CoV-2: Systematic Review and Meta-analysis

Coronavirus Disease 2019 (COVID-19), caused by the novel Severe Acute Respiratory Syndrome-associated Coronavirus 2 (SARS-CoV-2), has become a global threat to public health. COVID-19 is more pathogenic and infectious than the prior 2002 pandemic caused by SARS-CoV-1. The pathogenesis of certain disease manifestations in COVID-19 such as diffuse alveolar damage (DAD) are thought to be similar to SARS-CoV-1. However, the exact pathogenesis of COVID-19 related deaths remains poorly understood. The aim of this article was to systematically summarize the rapidly emerging literature regarding COVID-19 autopsies. A meta-analysis was also conducted based on data accrued from preprint and published articles on COVID-19 (n=241 patients) and the results compared with postmortem findings associated with SARS-CoV-1 deaths (n=91 patients). Both autopsy groups included mostly adults of median age 70 years with COVID-19 and 50 years with SARS-CoV-1. Overall, prevalence of DAD was more common in SARS-CoV-1 (100.0%) than COVID-19 (80.9%) autopsies (P=0.001). Extrapulmonary findings among both groups were not statistically significant except for hepatic necrosis (P <0.001), splenic necrosis (P<0.006) and white pulp depletion (P <0.001) that were more common with SARS-CoV-1. Remarkable postmortem findings in association with COVID-19 apart from DAD include pulmonary hemorrhage, viral cytopathic effect within pneumocytes, thromboembolism, brain infarction, endotheliitis, acute renal tubular damage, white pulp depletion of the spleen, cardiac myocyte necrosis, megakaryocyte recruitment, and hemophagocytosis.

Is Microthrombosis the Main Pathology in Coronavirus Disease 2019 Severity?-A Systematic Review of the Postmortem Pathologic Findings

This systematic review attempts to retrieve and report the findings of postmortem studies including the histopathologic data of deceased coronavirus disease 2019 patients and to review the manifestations of coronavirus disease 2019-associated thrombotic pathologies reported in the recent literature.

DATA SOURCES

PubMed, Excerpta Medica Database, and Cochrane library between December 1, 2019, and August 26, 2020.

STUDY SELECTION

Investigators screened 360 unique references, retrieved published autopsy series, and report on the postmortem histopathologic information on patients who had died of coronavirus disease 2019.

DATA EXTRACTION

Investigators independently abstracted all available data including study design, participant demographics, key histopathologic findings, disease severity markers, duration of hospital stay, and cause of death.

DATA SYNTHESIS

From the 65 eligible studies, 691 total completed autopsies were included in evidence synthesis. Histopathologic evaluation of the lungs revealed presence of diffuse alveolar damage in 323 of 443 patients and pulmonary microthrombi in 242 of 326 patients. Deep venous thrombosis and pulmonary embolism were found in 41% and ~15%, respectively, of the cadavers examined for thromboembolic events. d-dimer levels were generally higher in patients with severe clinical course of coronavirus disease 2019. Plasma levels of ferritin, lactate dehydrogenase, interleukin-6, and C-reactive protein were higher in nonsurvivors when compared with survivors. Overall, microthrombi and extensive angiogenesis of lung vasculature were the most common pathologic findings in the lungs and microthrombi in most of the assessed organ-tissue.

CONCLUSIONS

Diffuse alveolar damage was the most predominant feature in the lungs of coronavirus disease 2019 patients who underwent postmortem assessment. Widespread pulmonary microthrombosis and extensive pulmonary angiogenesis, in addition to frequent pulmonary and extrapulmonary microthrombotic and thromboembolic findings in patients with coronavirus disease 2019, appear to be consistent with the disease-specific hypercoagulability. Further discovery efforts in assessing the link between coronavirus disease 2019, hypercoagulable state, and immunothrombosis are warranted. In the interim, increased attention to anticoagulant treatment approaches in coronavirus disease 2019 patients is needed.

Pulmonary pathology of COVID-19: a review of autopsy studies

PURPOSE OF REVIEW

COVID-19 lung injury is a common manifestation of severe illness. Lung tissue examination has been largely derived from autopsy - a combination of case reports, small and moderately sized series with international scope. Common and uncommon histopathology provides insight into the progression of severe, fatal disease.

RECENT FINDINGS

COVID-19 lung histology is most commonly diffuse alveolar damage as part of acute respiratory distress syndrome. Lung injury can be temporally heterogeneous, with patterns of healing alongside new injury. Viral studies, including immunohistochemistry, RNA in-situ hybridization, and tissue-based Polymerase chain reaction (PCR) assist in discerning complications of therapy (e.g. ventilator-associated pneumonia) from primary viral-induced injury. Response to viral infection produces systemic effects, and one major manifestation is thrombosis of micro-circulation and larger vessels. Less common patterns include neutrophil-rich inflammation, raising speculation that neutrophil extra-cellular traps may play a role in both viral control and exaggerated immune response.

SUMMARY

The heterogeneity of fatal cases- persistence of viral infection in lung, clearance of virus but severe lung injury, thrombosis, and exaggerated immune response - suggest that antiviral, antithrombotic, anti-inflammatory, and supportive therapy play a role in treatment, but that the patient-specific cause and timing of the lung injury is important in choosing intervention.

Pathological Findings in COVID-19 as a Tool to Define SARS-CoV-2 Pathogenesis. A Systematic Review

Introduction: The World Health Organization declared the COVID-19 pandemic in March 2020. COVID-19 still represents a worldwide health emergency, which causesa severe disease that has led to the death of many patients. The pathophysiological mechanism of SARS-CoV-2 determining the tissue damage is not clear and autopsycan be auseful tool to improve the knowledge of this infection and, thus, it can help achieve a timely diagnosis and develop an appropriate therapy. This is an overview of the main post-mortem findings reporting data on the infection effects on several organs. Methods: A systematic literature search was conducted in the PubMed database searching for articles from 1 January to August 31, 2020. Thearticles were selected identifying words/concepts in the titles and/or abstracts that indicated the analysis of the morphological/pathological tissue injuries related to SARS-CoV-2 disease by several investigations. Results: A total of 63 articles were selected. The main investigated tissue was the lung showing a diffuse alveolar damage (DAD) frequently associated with pulmonary thrombotic microangiopathy. Inflammatory findings and vascular damage were observed in other organs such as heart, liver, kidney, brain, spleen, skin and adrenal gland. The immunohistochemical analysis showed tissue inflammatory cells infiltrates. The virus presence was detected by several investigations such as RT-PCR, immunohistochemistry and electron microscope, showing the effect ofSARS-CoV-2not exclusively in the lung. Discussion: The evidence emerging from this review highlighted the importance of autopsy to provide a fundamental base in the process of understanding the consequences ofSARS-CoV-2 infection. COVID-19 is strictly related to a hyper inflammatory state that seems to start with DAD and immuno-thrombotic microangiopathy. Massive activation of the immune system and microvascular damage might also be responsible for indirect damage to other organs, even if the direct effect of the virus on these tissues cannot be excluded.

Autopsy Tool in Unknown Diseases: The Experience with Coronaviruses (SARS-CoV, MERS-CoV, SARS-CoV-2)

In the last two decades, three unknown pathogens have caused outbreaks, generating severe global health concerns. In 2003, after nucleic acid genotyping, a new virus was named severe acute respiratory syndrome coronavirus (SARS-CoV). After nine years, another coronavirus emerged in the middle east and was named MERS-CoV (Middle East Respiratory Syndrome-Coronavirus). Finally, in December 2019, a new unknown coronavirus was isolated from a cluster of patients and was named SARS-CoV-2 (COVID-19, coronavirus disease 2019). This review aims to propose a complete overview of autopsy in the three coronaviruses over the past two decades, showing its pivotal role in the management of unknown diseases. A total of 116 studies fulfilled the inclusion criteria: 14 studies were collected concerning SARS-CoV (87 autopsy reports, from Asian and American countries), 2 studies for MERS-CoV (2 autopsy reports, from Middle-East Asian countries), and 100 studies on SARS-CoV-2 (930 autopsy reports). Analyzing the data obtained on COVID-19, based on the country criterion, a large number of post-mortem investigation were performed in European countries (580 reports), followed by American countries (251 reports). It is interesting to note that no data were found from the Oceanic countries, maybe because of the minor involvement of the outbreak. In all cases, autopsy provided much information about each unknown coronavirus. Despite advanced technologies in the diagnostic fields, to date, autopsy remains the gold standard method to understand the biological features and the pathogenesis of unknown infections, especially when awareness of a pathogen is restricted and the impact on the healthcare system is substantial. The knowledge gained through this technique may positively influence therapeutic strategies, ultimately reducing mortality.

Bacterial Superinfections Among Persons With Coronavirus Disease 2019: A Comprehensive Review of Data From Postmortem Studies

BACKGROUND

Limited clinical data suggest a ~16% prevalence of bacterial superinfections among critically ill patients with coronavirus disease 2019 (COVID-19).

METHODS

We reviewed postmortem studies of patients with COVID-19 published in English through September 26, 2020, for histopathologic findings consistent with bacterial lung infections.

RESULTS

Worldwide, 621 patients from 75 studies were included. The quality of data was uneven, likely because identifying superinfections was not a major objective in 96% (72/75) of studies. Histopathology consistent with a potential lung superinfection was reported in 32% (200/621) of patients (22-96 years old; 66% men). Types of infections were pneumonia (95%), abscesses or empyema (3.5%), and septic emboli (1.5%). Seventy-three percent of pneumonias were focal rather than diffuse. The predominant histopathologic findings were intra-alveolar neutrophilic infiltrations that were distinct from those typical of COVID-19-associated diffuse alveolar damage. In studies with available data, 79% of patients received antimicrobial treatment; the most common agents were beta-lactam/beta-lactamase inhibitors (48%), macrolides (16%), cephalosoprins (12%), and carbapenems (6%). Superinfections were proven by direct visualization or recovery of bacteria in 25.5% (51/200) of potential cases and 8% of all patients in postmortem studies. In rank order, pathogens included Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Lung superinfections were the cause of death in 16% of potential cases and 3% of all patients with COVID-19.

CONCLUSIONS

Potential bacterial lung superinfections were evident at postmortem examination in 32% of persons who died with COVID-19 (proven, 8%; possible, 24%), but they were uncommonly the cause of death.

Died with or Died of? Development and Testing of a SARS CoV-2 Significance Score to Assess the Role of COVID-19 in the Deaths of Affected Patients

Since December 2019, a new form of coronavirus, SARS-CoV-2, has spread from China to the whole word, raising concerns regarding Coronavirus Disease 2019 (COVID-19) endangering public health and life. Over 1.5 million deaths related with COVID-19 have been recorded worldwide, with wide variations among countries affected by the pandemic and continuously growing numbers. The aim of this paper was to provide an overview of the literature cases of deaths involving COVID-19 and to evaluate the application of the COVID-19 Significance Score (CSS) in the classification of SARS CoV-2-related fatalities, comparing it with the Hamburg rating scale. The results obtained allowed us to highlight that CSS used after a complete accurate post-mortem examination, coupled to the retrieval of in vivo data, post-mortem radiology, histology and toxicology, as well as to additional required analyses (e.g., electronic microscopy) is a useful and concise tool in the assessment of the cause of death and the role played by this virus. A shared use of this scale might hopefully lower the inhomogeneities in forensic evaluation of SARS CoV-2-related fatalities.

COVID-19 and the Heart: A Systematic Review of Cardiac Autopsies

Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated cardiac injury has been postulated secondary to several mechanisms. While tissue diagnosis is limited during the acute illness, postmortem studies can help boost our understanding and guide management. Objective: To report the cardiac tissue autopsy findings in coronavirus disease 2019 (COVID-19) decedents. Evidence Review: Articles published in PubMed and Embase reporting postmortem cardiac pathology of COVID-19 decedents till September 2020. We included adult studies excluding preprints. The Joanna Briggs Institute Critical Appraisal Checklist for Case Reports was used to assess quality. We extracted gross and histology data as well as the incidence of myocarditis, cardiac ischemia, thrombosis, and dilatation. We also looked at the reported cause of death (PROSPERO registration CRD42020190898). Findings: Forty-one relevant studies identified including 316 cases. The deceased were mostly male (62%) and elderly (median age, 75; range, 22-97 years). The most common comorbidities were hypertension (48%) and coronary artery disease (33%). Cardiac pathologies contributed to the death of 15 cases. Besides chronic cardiac pathologies, postmortem examination demonstrated cardiac dilatation (20%), acute ischemia (8%), intracardiac thrombi (2.5%), pericardial effusion (2.5%), and myocarditis (1.5%). SARS-CoV-2 was detected within the myocardium of 47% of studied hearts. Conclusions and Relevance: SARS-CoV-2 can invade the heart, but a minority of cases were found to have myocarditis. Cardiac dilatation, ischemia, mural, and microthrombi were the most frequent findings. The systematic review was limited by the small number of cases and the quality of the studies, and there is a need to standardize the cardiac postmortem protocols.

Neurologic complications of myocarditis

Myocarditis, a nonischemic acquired cardiomyopathy, is an uncommon condition with multiple presentation patterns which may be initially difficult to recognize and may simulate other conditions such as acute myocardial infarction, pericarditis, septicemia, etc. There are four distinct clinical presentation patterns that include: (1) low-grade nonspecific symptoms such as fatigue; (2) symptoms that resemble an acute myocardial infarction, especially in younger individuals; (3) a heart failure presentation which may be acute, subacute, or chronic and may be associated with cardiac conduction system defects and arrhythmias; and (4) an arrhythmia presentation that may produce sudden cardiac death, especially in young athletes with minimal or no prodromal symptoms. This chapter will provide a brief overview of various myocarditis etiologies and diagnostic modalities. The ultimate focus will be directed toward neurologic manifestations of myocarditis and its subtypes, complications of specific therapies including extracorporeal membrane oxygenation (ECMO) for refractory heart failure, and review the current literature regarding the appropriate use of therapeutic anticoagulation in myocarditis and heart failure for stroke prevention. Covid-19 infection has been discovered to cause myocarditis. The emerging science will be discussed. Nuances of brain death (BD) determination in patients receiving venoarterial ECMO for heart failure refractory to standard medical therapies will be discussed.

Lung Histopathology in Coronavirus Disease 2019 as Compared With Severe Acute Respiratory Sydrome and H1N1 Influenza: A Systematic Review

BACKGROUND

Patients with severe coronavirus disease 2019 (COVID-19) have respiratory failure with hypoxemia and acute bilateral pulmonary infiltrates, consistent with ARDS. Respiratory failure in COVID-19 might represent a novel pathologic entity.

RESEARCH QUESTION

How does the lung histopathology described in COVID-19 compare with the lung histopathology described in SARS and H1N1 influenza?

STUDY DESIGN AND METHODS

We conducted a systematic review to characterize the lung histopathologic features of COVID-19 and compare them against findings of other recent viral pandemics, H1N1 influenza and SARS. We systematically searched MEDLINE and PubMed for studies published up to June 24, 2020, using search terms for COVID-19, H1N1 influenza, and SARS with keywords for pathology, biopsy, and autopsy. Using PRISMA-Individual Participant Data guidelines, our systematic review analysis included 26 articles representing 171 COVID-19 patients; 20 articles representing 287 H1N1 patients; and eight articles representing 64 SARS patients.

RESULTS

In COVID-19, acute-phase diffuse alveolar damage (DAD) was reported in 88% of patients, which was similar to the proportion of cases with DAD in both H1N1 (90%) and SARS (98%). Pulmonary microthrombi were reported in 57% of COVID-19 and 58% of SARS patients, as compared with 24% of H1N1 influenza patients.

INTERPRETATION

DAD, the histologic correlate of ARDS, is the predominant histopathologic pattern identified in lung pathology from patients with COVID-19, H1N1 influenza, and SARS. Microthrombi were reported more frequently in both patients with COVID-19 and SARS as compared with H1N1 influenza. Future work is needed to validate this histopathologic finding and, if confirmed, elucidate the mechanistic underpinnings and characterize any associations with clinically important outcomes.

[Organ changes found by postmortem examination in COVID-19 patients]

The postmortem study results presented in 20 sources of literature on 186 COVID-19 patients were analyzed. Pathological changes were noted in multiple organs, by involving predominantly the respiratory, circulatory, and excretory systems. The changes in the lungs were characterized by an increase in organ weight (59.3%), a dark red color of the parenchyma (47.4%), compaction of lung tissue (56%), and signs of lung congestion (37.3%). The histological characteristics found during postmortem lung tissue examination, which were indicative of diffuse alveolar damage, were proliferation of type II alveolocytes in 65.2% of cases, the appearance of hyaline membranes lining the alveoli in 64.4%, and interstitial edema in 54.2%. In the analyzed sources, 22% of cases were noticed to have severe thrombosis and pulmonary artery branch embolism that was associated with lower extremity deep vein thrombosis. In all the sources of literature, acute tubular necrosis, tubular luminal dilatation, and interstitial edema were detected in the kidneys.

COVID-19 Induced Myocarditis: A Rare Cause of Heart Failure

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing lung injury has been well documented in the literature recently. They do so primarily by binding to the membrane-bound form of angiotensin-converting enzyme 2 (ACE-2) receptors. However, since these receptors are also expressed in the heart and blood vessels, coronavirus can also cause damage to these organs by binding to the ACE-2 receptors. A typical case of coronavirus disease 2019 (COVID-19) usually presents with respiratory symptoms like cough and shortness of breath accompanied by fever. The literature regarding this pandemic has been growing and now we know very well that the effect of this deadly virus is not restricted to the lungs alone. It can, unfortunately, cause various other complications ranging from neurological damage to even myocardial injury in rare cases. We present an interesting case of a 40-year-old male patient who presented to us with shortness of breath. When further investigated, the patient was found to have a new onset of heart failure secondary to COVID-19 induced myocarditis.

Neuroinvasive potential of SARS-CoV2 with neuroradiological and neuropathological findings: is the brain a target or a victim?

Coronaviridae family includes pathogen viruses for humans, that lead to clinical conditions with main respiratory involvement; many of these viruses have notoriously a neuroinvasive potential, as demonstrated by published data on SARS-CoV and MERS-CoV epidemics, as well by results obtained in experimental models. During pandemic of coronavirus disease 2019 (COVID-19), it is noticed that the central nervous system involvement represented a truly significant moment in the history of some COVID-19 patients; indeed, clinical and radiological features published in literature regarding COVID-19 disease are consistent with a neurological involvement. It is also known that histopathological data related to SARS-CoV2 infection have been published with considerable delay, which was even greater for neuropathological information. Moreover, many published data are incomplete, and often the lesions described are not directly related to the action of the virus. In this review, we collected the available radiological and neuropathological information, in order to delineate a more complete picture of the relationship between SARS-Cov2 and brain, focusing our attention on the two most important neuroinvasion routes for the virus. We also highlighted what we consider methodological mistakes both in the autopsy procedures and brain study in COVID-19 deaths. We emphasize the need for a complete study of all the organs in case of autopsy. It is important that through this experience, we no longer do the mistake of neglecting the brain.

COVID-19-Associated Nonocclusive Fibrin Microthrombi in the Heart

Supplemental Digital Content is available in the text.

Background:

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resultant clinical presentation, coronavirus disease 2019 (COVID-19), is an emergent cause of mortality worldwide. Cardiac complications secondary to this infection are common; however, the underlying mechanisms of such remain unclear. A detailed cardiac evaluation of a series of individuals with COVID-19 undergoing postmortem evaluation is provided, with 4 aims: (1) describe the pathological spectrum of the myocardium; (2) compare with an alternate viral illness; (3) investigate angiotensin-converting enzyme 2 expression; and (4) provide the first description of the cardiac findings in patients with cleared infection.

Methods:

Study cases were identified from institutional files and included COVID-19 (n=15: 12 active, 3 cleared), influenza A/B (n=6), and nonvirally mediated deaths (n=6). Salient information was abstracted from the medical record. Light microscopic findings were recorded. An angiotensin-converting enzyme 2 immunohistochemical H-score was compared across cases. Viral detection encompassed SARS-CoV-2 immunohistochemistry, ultrastructural examination, and droplet digital polymerase chain reaction.

Results:

Male sex was more common in the COVID-19 group (P=0.05). Nonocclusive fibrin microthrombi (without ischemic injury) were identified in 16 cases (12 COVID-19, 2 influenza, and 2 controls) and were more common in the active COVID-19 cohort (P=0.006). Four active COVID-19 cases showed focal myocarditis, whereas 1 case of cleared COVID-19 showed extensive disease. Arteriolar angiotensin-converting enzyme 2 endothelial expression was lower in COVID-19 cases than in controls (P=0.004). Angiotensin-converting enzyme 2 myocardial expression did not differ by disease category, sex, age, or number of patient comorbidities (P=0.69, P=1.00, P=0.46, P=0.65, respectively). SARS-CoV-2 immunohistochemistry showed nonspecific staining, whereas ultrastructural examination and droplet digital polymerase chain reaction were negative for viral presence. Four patients (26.7%) with COVID-19 had underlying cardiac amyloidosis. Cases with cleared infection had variable presentations.

Conclusions:

This detailed histopathologic, immunohistochemical, ultrastructural, and molecular cardiac series showed no definitive evidence of direct myocardial infection. COVID-19 cases frequently have cardiac fibrin microthrombi, without universal acute ischemic injury. Moreover, myocarditis is present in 33.3% of patients with active and cleared COVID-19 but is usually limited in extent. Histological features of resolved infection are variable. Cardiac amyloidosis may be an additional risk factor for severe disease.

Insights into pathogenesis of fatal COVID-19 pneumonia from histopathology with immunohistochemical and viral RNA studies

Introduction

We describe post‐mortem pulmonary histopathologic findings of COVID‐19 pneumonia in patients with a spectrum of disease course, from rapid demise to prolonged hospitalisation.

Methods and results

Histopathologic findings in post‐mortem lung tissue from eight patients who died from COVID‐19 pneumonia were reviewed. Immunohistochemistry (IHC) and next‐generation sequencing (NGS) were performed to detect virus. Diffuse alveolar damage (DAD) was seen in all cases with a spectrum of acute phase and/or organising phase. IHC with monoclonal antibodies against SARS‐CoV‐2 viral nucleoprotein and spike protein detected virus in areas of acute but not organising DAD, with intracellular viral antigen and RNA expression seen predominantly in patients with duration of illness less than 10 days. Major vascular findings included thrombi in medium‐ and large‐calibre vessels, platelet microthrombi detected by CD61 IHC and fibrin microthrombi.

Conclusions

Presence of SARS‐CoV‐2 viral RNA by NGS early in the disease course and expression of viral antigen by IHC exclusively in the acute, but not in the organising phase of DAD, suggests that the virus may play a major role in initiating the acute lung injury of DAD, but when DAD progresses to the organising phase the virus may have been cleared from the lung by the patient's immune response. These findings suggest the possibility of a major change during the disease course of COVID‐19 pneumonia that may have therapeutic implications. Frequent thrombi and microthrombi may also present potential targets for therapeutic intervention.

Imaging Diagnostics and Pathology in SARS-CoV-2-Related Diseases

In December 2019, physicians reported numerous patients showing pneumonia of unknown origin in the Chinese region of Wuhan. Following the spreading of the infection over the world, The World Health Organization (WHO) on 11 March 2020 declared the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) outbreak a global pandemic. The scientific community is exerting an extraordinary effort to elucidate all aspects related to SARS-CoV-2, such as the structure, ultrastructure, invasion mechanisms, replication mechanisms, or drugs for treatment, mainly through in vitro studies. Thus, the clinical in vivo data can provide a test bench for new discoveries in the field of SARS-CoV-2, finding new solutions to fight the current pandemic. During this dramatic situation, the normal scientific protocols for the development of new diagnostic procedures or drugs are frequently not completely applied in order to speed up these processes. In this context, interdisciplinarity is fundamental. Specifically, a great contribution can be provided by the association and interpretation of data derived from medical disciplines based on the study of images, such as radiology, nuclear medicine, and pathology. Therefore, here, we highlighted the most recent histopathological and imaging data concerning the SARS-CoV-2 infection in lung and other human organs such as the kidney, heart, and vascular system. In addition, we evaluated the possible matches among data of radiology, nuclear medicine, and pathology departments in order to support the intense scientific work to address the SARS-CoV-2 pandemic. In this regard, the development of artificial intelligence algorithms that are capable of correlating these clinical data with the new scientific discoveries concerning SARS-CoV-2 might be the keystone to get out of the pandemic.

Increased number of pulmonary megakaryocytes in COVID-19 patients with diffuse alveolar damage: an autopsy study with clinical correlation and review of the literature

Pulmonary megakaryocytes participate in the pathogenesis of lung damage, particularly in acute lung injury. Although megakaryocytes are not mentioned as a characteristic histologic finding associated to pulmonary injury, a few studies reveal that their number is increased in diffuse alveolar damage (DAD). In this autopsy study, we have observed a relevant number of pulmonary megakaryocytes in COVID-19 patients dying with acute lung injury (7.61 ± 5.59 megakaryocytes per 25 high-power fields vs. 1.14 ± 0.86 for the control group, p < 0.05). We analyzed samples of 18 patients, most of whom died after prolonged disease and use of mechanical ventilation. Most patients showed advanced DAD and abnormal coagulation parameters with high levels of fibrinogen, D-dimers, and variable thrombocytopenia. For comparison, pulmonary samples from a group of 14 non-COVID-19 patients dying with DAD were reviewed. They showed similar pulmonary histopathologic findings and an increase in the number of megakaryocytes (4 ± 4.17 vs. 1.14 ± 0.86 for the control group, p < 0.05). Megakaryocyte count in the COVID-19 group was greater but did not reach statistical significance (7.61 ± 5.59 vs. 4 ± 4.17, p = 0.063). Regardless of the cause, pulmonary megakaryocytes are increased in patients with DAD. Their high number seen in COVID-19 patients suggests a relation with the thrombotic events so often seen these patients. Since the lung is considered an active site of megakaryopoiesis, a prothrombotic status leading to platelet activation, aggregation and consumption may trigger a compensatory pulmonary response.

Pulmonary pathology and COVID-19: lessons from autopsy. The experience of European Pulmonary Pathologists

Since its initial recognition in December 2019, Coronavirus disease 19 (COVID-19) has quickly spread to a pandemic infectious disease. The causative agent has been recognized as a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), primarily affecting the respiratory tract. To date, no vaccines are available nor any specific treatment. To limit the number of infections, strict directives have been issued by governments that have been translated into equally rigorous guidelines notably for post-mortem examinations by international and national scientific societies. The recommendations for biosafety control required during specimen collection and handling have strongly limited the practice of autopsies of the COVID-19 patients to a few adequate laboratories. A full pathological examination has always been considered an important tool to better understand the pathophysiology of diseases, especially when the knowledge of an emerging disorder is limited and the impact on the healthcare system is significant. The first evidence of diffuse alveolar damage in the context of an acute respiratory distress syndrome has now been joined by the latest findings that report a more complex scenario in COVID-19, including a vascular involvement and a wide spectrum of associated pathologies. Ancillary tools such as electron microscopy and molecular biology used on autoptic tissue samples from autopsy are also significantly contributing to confirm and/or identify new aspects useful for a deeper knowledge of the pathogenetic mechanisms. This article will review and summarize the pathological findings described in COVID-19 until now, chiefly focusing on the respiratory tract, highlighting the importance of autopsy towards a better knowledge of this disease.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and coronavirus disease 19 (COVID-19) - anatomic pathology perspective on current knowledge

BACKGROUND

The world is currently witnessing a major devastating pandemic of Coronavirus disease-2019 (COVID-19). This disease is caused by a novel coronavirus named Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). It primarily affects the respiratory tract and particularly the lungs. The virus enters the cell by attaching its spike-like surface projections to the angiotensin-converting enzyme-2 (ACE-2) expressed in various tissues. Though the majority of symptomatic patients have mild flu-like symptoms, a significant minority develop severe lung injury with acute respiratory distress syndrome (ARDS), leading to considerable morbidity and mortality. Elderly patients with previous cardiovascular comorbidities are particularly susceptible to severe clinical manifestations. BODY: Currently, our limited knowledge of the pathologic findings is based on post-mortem biopsies, a few limited autopsies, and very few complete autopsies. From these reports, we know that the virus can be found in various organs but the most striking tissue damage involves the lungs resulting almost always in diffuse alveolar damage with interstitial edema, capillary congestion, and occasional interstitial lymphocytosis, causing hypoxia, multiorgan failure, and death. A few pathology studies have also reported intravascular microthrombi and pulmonary thrombembolism. Although the clinical presentation of this disease is fairly well characterized, knowledge of the pathologic aspects remains comparatively limited.

CONCLUSION

In this review, we discuss clinical, pathologic, and genomic features of COVID-19, review current hypotheses regarding the pathogenesis, and briefly discuss the clinical characteristics. We also compare the salient features of COVID-19 with other coronavirus-related illnesses that have posed significant public health issues in the past, including SARS and the Middle East Respiratory Syndrome (MERS).

Alveolar macrophage dysfunction and cytokine storm in the pathogenesis of two severe COVID-19 patients

BACKGROUND

The novel coronavirus pneumonia COVID-19 caused by SARS-CoV-2 infection could lead to a series of clinical symptoms and severe illnesses, including acute respiratory distress syndrome (ARDS) and fatal organ failure. We report the fundamental pathological investigation in the lungs and other organs of fatal cases for the mechanistic understanding of severe COVID-19 and the development of specific therapy in these cases.

METHODS

The autopsy and pathological investigations of specimens were performed on bodies of two deceased cases with COVID-19. Gross anatomy and histological investigation by Hematoxylin and eosin (HE) stained were reviewed on each patient. Alcian blue/periodic acid-Schiff (AB-PAS) staining and Masson staining were performed for the examinations of mucus, fibrin and collagen fiber in lung tissues. Immunohistochemical staining was performed on the slides of lung tissues from two patients. Real-time PCR was performed to detect the infection of SARS-CoV-2. Flow cytometry analyses were performed to detect the direct binding of S protein and the expression of ACE2 on the cell surface of macrophages.

FINDINGS

The main pathological features in lungs included extensive impairment of type I alveolar epithelial cells and atypical hyperplasia of type II alveolar cells, with formation of hyaline membrane, focal hemorrhage, exudation and pulmonary edema, and pulmonary consolidation. The mucous plug with fibrinous exudate in the alveoli and the dysfunction of alveolar macrophages were characteristic abnormalities. The type II alveolar epithelial cells and macrophages in alveoli and pulmonary hilum lymphoid tissue were infected by SARS-CoV-2. S protein of SARS-CoV-2 directly bound to the macrophage via the S-protein-ACE2 interaction.

INTERPRETATION

Infection of alveolar macrophage by SARS-CoV-2 might be drivers of the "cytokine storm", which might result in damages in pulmonary tissues, heart and lung, and lead to the failure of multiple organs .

FUNDING

Shanghai Guangci Translational Medical Research Development Foundation, Shanghai, China.

Histopathologic Findings of Coronavirus in Lung: A Mini-Review

Coronaviruses (CoVs) are important human and animal pathogens. There have been several outbreaks of lung involvement by this category of viruses in the world, ie, severe acute respiratory syndrome (SARS-CoV-1) in 2002 and 2003, the Middle East respiratory syndrome (MERS-CoV) in 2012, and the new coronavirus (2019-nCoV) outbreak of pneumonia from Wuhan, China, since December 2019. There have been several studies about the clinical features and imaging features, but very few reports have been published about pathologic findings in lung tissue, which was partly because of the lack of tissue diagnosis secondary to suddenness of the outbreak. Overall, less than 30 reports have been published in the literature about histologic findings of lung in these viruses, so far. In this report, we will review the published reports about the histopathologic findings of lung tissue in the patients infected with SARS-CoV-2 in comparison with 2 other coronaviruses that have caused outbreaks, ie, SARS-CoV-1 and MERS-CoV.