Although the number of patients examined is small, this is the largest study to date of post-mortem examinations on COVID-19 patients in England.
COVID-19 is a new disease, and scientists have only had limited opportunities to comprehensively analyze tissues from patients at autopsy, to better understand what caused a patient’s illness and death for research purposes.
In a recent study at Imperial College London and elsewhere, researchers performed 10 post-mortem examinations on patients with confirmed COVID-19.
They found that all patients had lung injuries and early scarring of the lungs as a result of the virus, as well as injury to their kidneys.
Nine patients also had thrombosis—a blood clot- in at least one major organ (heart, lung, or kidney).
The researchers believe that the findings could help guide clinicians on treating complications as a result of COVID-19, such as using blood thinners to prevent blood clots from developing.
They also hope that a better understanding of the key complications in severe cases could help clinicians develop new ways to monitor and treat the disease.
The study is published in The Lancet Microbe. One author is Dr. Michael Osborn, Honorary Clinical Senior Lecturer.
The team performed full post-mortem examinations and biopsies on ten patients aged 22-97 at Imperial College Healthcare NHS Trust hospitals during March-June.
Seven of the patients were men and four were women.
In the patients studied, high blood pressure and chronic obstructive pulmonary disease—the name for a group of lung conditions that cause breathing difficulties—were the most common contributing factors to death.
All patients developed a fever and had at least two respiratory symptoms such as cough and shortness of breath during the early stages of the disease.
Most patients died within three weeks of presenting with symptoms and treatments varied across the cohort.
The study team also reported six main findings:
All patients had diffuse alveolar damage (DAD). DAD is a term used to describe a pattern of lung injury which can be seen as a result of viral infection.
This type of lung injury can affect both gas exchange (oxygen and carbon dioxide) and blood flood in the lungs.
All patients fully assessed nine of the ten patients had some form of thrombosis- a blood clot—in at least one major organ.
Thrombosis prevents blood from flowing normally through the circulatory system and can lead to strokes and heart attacks.
The researchers found thrombi in the lungs of eight patients, the heart of five patients, and the kidneys of four patients.
They believe that this supports the theory that COVID-19 causes circulatory complications and that patient treatment could be augmented with blood-thinning medication to prevent blood clots.
All patients had evidence of acute renal tubular injury—a kidney injury that can lead to kidney failure or damage.
The main causes are low blood flow to the kidneys and severe infections. It often affects patients who are in hospital and intensive care units
T-Lymphocyte Depletion (TLD) in the spleen and the lymph nodes was another consistent finding. T-lymphocytes (white blood cells) are a major component of the immune system and play a role in destroying infections.
TLD is a reduction in T-lymphocytes, which alters the immune system and its response.
Haemophagocytosis is another consistent finding in this group, which occurs when the immune system overreacts to an infection and destroys some of its own cells
The researchers found evidence of acute pancreatitis in two of the patients. Acute pancreatitis is a condition where the pancreas becomes inflamed.
It can be treated with fluids into the veins but in some cases can develop into serious complications and cause organ failure.
Damage to the pancreas in COVID-19 patients has not been reported before but it is not clear in this study whether the pancreatitis was related to COVID-19 infection or other causes
The researchers also found evidence of a rare fungal infection, in one of the patients, called Mucormycosis.
Mucormycosis is an infection that may spread through the bloodstream to affect another part of the body. Severe infections can involve the lungs, brain, and other organs including the kidneys, spleen, and heart.
The team now is working with a range of research groups to perform more detailed analyses of these issues and is hoping that this research will expand to include a wider range of patients.
Copyright © 2020 Knowridge Science Report. All rights reserved.
