ABSTRACT
The major targets of coronavirus disease 2019 (COVID-19) are the respiratory and immune systems. However, a significant proportion of hospitalized patients had kidney dysfunction. The histopathological surveys have principally focused on respiratory, hematopoietic, and immune systems, whereas histopathologic data of kidney injury are lacking. Our study aimed to summarize the renal histopathological findings in COVID-19 from the published case report and case series. We conducted a systematic searching of databases such as MEDLINE, EMBASE, and Cochrane Library for published reports of COVID-19 patients with renal histopathological changes from autopsy studies and from "for cause" indication biopsies. Included in our study are case reports and case series with extractable quantitative data on patient demographics such as age, sex, ethnicity, as well as data on renal function tests, their comorbidities, and biopsy to study the histopathological changes. Data were analyzed with Microsoft Excel. To evaluate the methodological quality, we chose the framework for appraisal, synthesis, and application of evidence suggested by Murad et al. Systematic searches of literature found 31 studies that fulfilled the eligibility criteria. These studies included a total of 139 cases, where individual case details including clinical and histopathological findings were available. The median age of the cases was 62 years with a male:female ratio of 2.5:1. Associated comorbidities were noted in 78.4% of cases. The majority of the cases had renal dysfunction with proteinuria which was documented in more than two-thirds of the cases. The histopathological findings observed the frequent tubular involvement manifested by acute tubular injury. Regarding glomerular pathology, collapsing glomerulopathy emerged as a distinct lesion in these patients and was noted among 46.8% of cases with glomerular lesions. A small subset of cases (4.3%) had thrombotic microangiopathy. Collapsing glomerulopathy emerged as a hallmark of glomerular changes among COVID-19 patients. Tubular damage is common and is linked to multiple factors including ischemia, sepsis among others. In the form of thrombotic microangiopathy seen in a subset of patients, vascular damage hints toward the hyper-coagulable state associated with the infection. The demonstration of viral particles in renal tissue remains debatable and requires further study.
Subject(s)
COVID-19 , Kidney Diseases , Thrombotic Microangiopathies , Female , Humans , Kidney/pathology , Kidney/physiology , Kidney Diseases/pathology , Kidney Glomerulus/pathology , Male , Middle Aged , Proteinuria/etiology , Thrombotic Microangiopathies/complicationsABSTRACT
Objectives The 2019 novel coronavirus (2019-nCoV) has spread across the globe with more than 6 lakh deaths. Clinical autopsies are important to understand the pathobiology of the disease. Materials and Methods Autopsy techniques have been modified to be minimally invasive autopsies in all COVID-19 positive cases, and tissue biopsies were sampled from lungs, liver, and bone marrow within an hour after death. Detailed histological analysis was performed in the sampled tissues, along with immunohistochemistry. Patients' clinical records were collected. Statistical Analysis Descriptive statistics were used to summarize data. Results Of the 21 cases studied, 76.2% patients were ≥ 60 years of age, 80.9% were males, and 85.7% had co-morbidities. Histopathological analysis revealed diffuse alveolar damage (including exudative and organizing phase) in 88.9% cases. Microthrombi were seen in 44.4% cases. Additional findings include viral cytopathic changes, metaplastic change in the epithelium, intra-alveolar hemorrhage, and pulmonary edema. Liver showed centrizonal congestion with hepatocytic loss, lobular inflammation, steatosis, Kupffer cell hypertrophy, and sinusoidal neutrophilic infiltration, while significant portal infiltrate and cholestasis were absent to minimal. Bone marrow revealed hemophagocytosis in 60% cases. Conclusion Incorporation of minimally invasive autopsies provides an effective method to study the pathological findings in COVID-19 deaths in resource-constrained settings. Presence of pulmonary microthrombi in a significant number of cases supports the vascular events, apart from the characteristic diffuse alveolar damage, as an important pathogenic mechanism for lung injury in COVID-19 infections. Histopathological findings in the liver and bone marrow suggest indirect insult to these organs, related to circulatory and/or hyperinflammatory response to viral infections.
ABSTRACT
BACKGROUND: The outbreak ofsevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has resulted inexponential rise in the number of patients getting hospitalised with corona virus disease 2019 (COVID-19). There is a paucity of data from South East Asian Region related to the predictors of clinical outcomes in these patients. This formed the basis of conducting our study. METHODS: This was an analytical cross-sectional study. Demographic, clinical, radiological and laboratory data of 125 patients was collected on admission. The study outcome was death or discharge after recovery. For univariate analysis, unpaired t-test, Chi-square and Fisher's Exact test were used. Receiver operating characteristic (ROC) curves were plotted for Sequential Organ Failure Assessment (SOFA) score and few laboratory parameters. Logistic regression was applied for multivariate analysis. RESULTS: Elderly age, ischemic heart disease and smoking were significantly associated with mortality. Elevated levels of D-dimer and lactate dehydrogenase (LDH) and reduced lymphocyte counts were the predictors of mortality. The ROCs for SOFA score curve showed a cut-off value ≥ 3.5 (sensitivity- 91.7% and specificity- 87.5%), for IL-6 the cut-off value was ≥ 37.9 (sensitivity- 96% and specificity- 78%) and for lymphocyte counts, a cut off was calculated to be less than and equal to 1.46 x 109per litre (sensitivity-75.2%and specificity- 83.3%). CONCLUSION: Old age, smoking history, ischemic heart disease and laboratory parameters including elevated D-dimer, raised LDH and low lymphocyte counts at baseline are associated with COVID-19 mortality. A higher SOFA score at admission is a poor prognosticator in COVID-19 patients.