Evaluation of Pathological Findings of COVID-19 by Minimally Invasive Autopsies: A Single Tertiary Care Center Experience from India

Histopathological impact of SARS-CoV-2 on the liver: Cellular damage and long-term complications

Coronavirus disease 2019 (COVID-19), caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome, multiple organ failure, and death. Despite extensive studies on the pathogenicity of SARS-CoV-2, its impact on the hepatobiliary system remains unclear. While liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels, the exact source of this damage is not fully understood. Proposed mechanisms for injury include direct cytotoxicity, collateral damage from inflammation, drug-induced liver injury, and ischemia/hypoxia. However, evidence often relies on blood tests with liver enzyme abnormalities. In this comprehensive review, we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients, drawing from liver biopsies, complete autopsies, and in vitro liver analyses. We present evidence of the direct impact of SARS-CoV-2 on the liver, substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes, including mitochondrial swelling, endoplasmic reticulum dilatation, and hepatocyte apoptosis. Additionally, we describe the diverse liver pathology observed during COVID-19 infection, encompassing necrosis, steatosis, cholestasis, and lobular inflammation. We also discuss the emergence of long-term complications, notably COVID-19-related secondary sclerosing cholangitis. Recognizing the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making.

Stabilization of Comminuted Fractures of the Proximal Humerus with Intramedullary Nails and Angularly Stable Locking Plates—Functional Results before and during the SARS-COVID-19 Pandemics

Background and Objectives: Intramedullary nailing (IMN) and angularly stable plating (ASP) are the most popular techniques for the stabilization of comminuted fractures of the proximal humerus, without either one being obviously superior. The aim of the study was to validate the functional outcomes of both stabilization techniques in the COVID-19 pandemic by comparing them with data obtained just before the pandemic, because the limitations of the COVID-19 pandemic are affecting several aspects of social and medical life—being afraid of the transmission of the infection, patients reduce their exposure to healthcare to absolutely essential emergencies. Moreover, working conditions in the operating theater have also become more restrictive. Materials and Methods: Investigations were performed on 112 adult patients with Neer’s three- and four-fragment fractures stabilized with IMN (64) and ASP (48). Treatment effects were validated six months after surgery based on radiographs for evidence of bone union, humeral neck–shaft angle (NSA) and implant placement. Limb function was assessed with the QuickDash and Constant–Murley scores. Data obtained from patients treated in the COVID-19 pandemic were compared with those obtained before the pandemic. Results: The healing of all fractures was satisfactory, but complications developed in six cases. Three patients required secondary interventions due to inadequate repositioning: one after IMN and two after ASP. Additionally, one ASP was complicated by the secondary destabilization of a primarily properly stabilized major tubercle, and in two cases by conflict of the protruding implant with the acromion. ASP was noted to provide better functional results during the COVID-19 pandemic according to the Constant–Murley score (p = 0.0048; Student’s t-test). No significant differences were observed in the pre-COVID-19 pandemic. Conclusions: Our results suggest that ASP is more beneficial for the stabilization of comminuted fractures of the proximal humerus during the COVID-19 pandemic.

Digestive system infection by SARS‑CoV‑2: Entry mechanism, clinical symptoms and expression of major receptors (Review)

Besides causing severe acute respiratory syndrome (SARS), SARS‑coronavirus 2 (SARS‑CoV‑2) also harms the digestive system. Given the appearance of numerous cases of SARS‑CoV‑2, it has been demonstrated that SARS‑CoV‑2 is able to harm target organs such as the gastrointestinal tract, liver and pancreas, and either worsen the condition of patients with basic digestive illnesses or make their prognosis poor. According to several previously published studies, angiotensin‑converting enzyme II (ACE2) and transmembrane serine protease II (TMPRSS2) are expressed either singly or in combination in the digestive system and in other regions of the human body. In order to change the viral conformation, create a fusion hole and release viral RNA into the host cell for replication and transcription, SARS‑CoV‑2 is capable of binding to these two proteins through the spike protein on its surface. As a result, the body experiences an immune reaction and an inflammatory reaction, which may lead to nausea, diarrhea, abdominal pain and even gastrointestinal bleeding, elevated levels of liver enzymes, acute liver injury, pancreatitis and other serious lesions. In order to provide possible strategies for the clinical diagnosis and treatment of digestive system diseases during the COVID‑19 pandemic, the molecular structure of SARS‑CoV‑2 and the mechanism via which SARS‑CoV‑2 enters the human body through ACE2 and TMPRSS2 were discussed in the present review, and the clinical manifestations of SARS‑CoV‑2 infection in the digestive system were also summarized. Finally, the expression characteristics of ACE2 and TMPRSS2 in the main target organs of the digestive system were described.

MINIMAL LIVER ENZYMES ABNORMALITIES AT ADMISSION ARE RELATED TO SEVERE COVID-19 CLINICAL COURSE IN A LARGE BRAZILIAN COHORT

BACKGROUND

COVID-19 is a multisystemic disease, primarily affecting the respiratory system. Liver involvement is frequent, but the impact on the clinical course and outcomes are controversial.

OBJECTIVE

The aim was to assess liver function at the admission and evaluate its effects on severity and mortality in hospitalized patients with COVID-19.

METHODS

This is a retrospective study of hospitalized patients in a tertiary hospital in Brazil, with a PCR-confirmed SARS-CoV-2 infection between April and October 2020. 1080 out of 1229 patients had liver enzymes on admission and were divided in two cohorts, based on the presence or absence of abnormal liver enzymes (ALE). Demographic, clinical, laboratory, imaging, clinical severity, and mortality were evaluated. Patients were followed until discharge, death or transfer to another institution.

RESULTS

Median age was 60 years and 51.5% were male. The more frequent comorbidities were hypertension (51.2%), and diabetes (31.6%). Chronic liver disease and cirrhosis were present in 8.6% and 2.3%, respectively. ALE (aminotransferases higher than 40 IU/L) were present in 56.9% of patients [mild (1-2 times): 63.9%; moderate (2-5 times): 29.8%; severe (>5 times): 6.3%]. Male gender [RR 1.49, P=0.007], increased total bilirubin [RR 1.18, P<0.001] and chronic liver disease [RR 1.47, P=0.015] were predictors of abnormal aminotransferases on admission. Patients with ALE had a higher risk of disease severity [RR 1.19; P=0.004]. There was no association among ALE and mortality.

CONCLUSION

ALE is common in COVID-19 hospitalized patients and were independently correlated with severe COVID-19. Even mild ALE at admission may be a severity prognostic marker.

Ultrastructural Changes in Autopsy Tissues of COVID-19 Patients

INTRODUCTION

The COVID-19 pandemic resulted in substantial morbidity and mortality across the world. The prognosis was found to be poor in patients with co-morbidities such as diabetes, hypertension, interstitial lung disease, etc. Although biochemical studies were done in patient samples, no study has been reported from the Indian subcontinent about ultrastructural changes in the vital organs of COVID-19 patients. The present study was, therefore, conducted to understand the ultrastructural changes in the lung, liver, and brain of the deceased patients.

METHODS

The present study was conducted on samples obtained from reverse transcription-polymerase chain reaction (RT-PCR)-positive patients who were admitted to a tertiary care hospital in Western India. Core needle biopsies were done in eight fatal cases of COVID-19. The samples were taken from the lungs, liver, and brain and subjected to light microscopy, immunohistochemistry (IHC), and transmission electron microscopy (TEM). Clinical details and biochemical findings were also collected.  Results: The study participants included seven males and one female. The presenting complaints included fever, breathlessness, and cough. Light microscopy revealed diffuse alveolar damage in the lungs. Further, a positive expression of SARS-CoV-2 nucleocapsid protein was observed in the pulmonary parenchyma of five patients. Also, the TEM microphotograph showed viral particles of size up to 80nm localized in alveolar epithelial cells. However, no viral particles were found in liver or brain samples. In the liver, macrovesicular steatosis and centrizonal congestion with loss of hepatocytes were observed in light microscopy.

CONCLUSION

 This is the first study in the Indian population showing the in-situ presence of viral particles in core biopsies from fatal cases of COVID-19. As evident from the results, histology and ultrastructural changes in the lung correlated with the presence of viral particles. The study revealed a positive correlation between the damage in the lungs and the presence of viral particles.

Roles of the ACE/Ang II/AT1R pathway, cytokine release, and alteration of tight junctions in COVID-19 pathogenesis

This paper shows how SARS-CoV-2 alters tight junctions (TJs) in human organs. The effect of SARS-CoV-2 on the ACE/Ang II/AT1R pathway and immune cells culminates in the release of numerous pro-inflammatory mediators, leading to the presence of certain symptoms in COVID-19, such as acute lung injury (ALI), pulmonary hypertension, and pulmonary fibrosis. Furthermore, the cytokines released alter different TJs components. The study shows how the irregular release of pro-inflammatory cytokines leads to claudin disruption in various tissues of the body, resulting in different symptoms, such as alveolar fibrosis, pulmonary edema, conjunctivitis, altered fertility in males, gastrointestinal symptoms, Covid toes, and others. SARS-CoV-2 also alters occludin expression in the endothelial and blood-testis barriers (BTB) resulting in edema and altered fertility. Viral disruption of JAM-A leads to activation of the RhoA GTPase, which leads to ALI. Taken together, these results define ACE/Ang II/AT1R pathway receptors and tight junctional components as potential therapeutic targets in COVID-19.