Unlike other virulent infections that may not cause symptoms, SARS-CoV-2 can cause pathological changes in the asymptomatic infected.
Modern medicine emphasizes – and rightly so – the importance of science.
The focus, however, frequently shifts our attention from the true goal of medical care: care (of patients).
This idea was captured by William Osler’s (1849-1919) warning to care for the patient rather than the disease. I rediscovered the truth of her advice when two patients in particular taught me about the covid-19 infection and questioned my experience of managing pneumonia.
The first covid-19 patient to present at my hospital was probably typical of initial patients in many other hospitals at the time.
He was an older man with pneumonia, who had not yet been tested for the new coronavirus, but was supposed to have it.
A team of experts carefully evaluated him, prescribed high-flow oxygen, and monitored him on a respiratory guard. That night, he died unexpectedly.
The second patient was a middle-aged woman sent to an intensive care unit to be connected to mechanical ventilation.
The recent death had made me nervous, so I went to evaluate it. On the way to the guard, I imagined what awaited me: a patient with great difficulty breathing, barely able to speak, her chest heaving with the effort of trying to bring oxygen to her blood.
When I arrived covered in my protective gear and ready to sedate and intubate her immediately, I thought I was facing the wrong bed.
She was sitting comfortably on her bed, talking on her mobile to her daughter, surprised by my appearance. Super-cautious colleagues, I thought. But I measured her blood oxygen saturation out of doubt, more out of instinct than out of concern.
Due to its appearance, I expected it to be normal (100%). It was 75%, a level barely compatible with consciousness.
Silent lung damage
I quickly learned that many advanced covid-19 patients did not have any of the hallmarks of severe respiratory disease until they suddenly collapsed and died.
The science behind this early lesson is now emerging, with a study from Wuhan, China, describing the pathological changes of the lung in the tomography of completely asymptomatic patients.
Lack of symptoms is not uncommon in other virulent infections, such as Staphylococcus aureus resistant to methicillin or MRSA and C diff (Clostridioides difficile), but what is striking with SARS-CoV-2 (the virus that causes covid-19) is that it may be accompanied by underlying organic damage.
The researchers found injuries consistent with inflammation of the underlying lung tissue (ground glass and consolidation opacities, to use medical jargon), which are not specific to SARS-CoV-2 infection and can be seen in many other lung diseases.
What remains a mystery This is why, despite these changes, patients do not display typical pneumonia symptoms, such as severe shortness of breath.
About a quarter of the patients in the study developed fever, cough, and shortness of breath, but many did not.
The idiosyncratic response to infection is one of several mysteries posed by covid-19, such as why it attacks certain groups and not others: Two people with exactly the same demographics and health can express the disease at opposite ends of the spectrum. .
The study reinforces that the absence of symptoms does not imply absence of damage.
The lack of symptoms against an active pathology entails a risk to both infected people and the public.
Current recommendations encourage patients to stay home if they are asymptomatic, making late hospital presentation and sudden death a risk.
And there is also the public health nightmare, since about 40-45% of people infected with SARS-CoV-2 are asymptomatic, with a viral load just as high than that of those who are actively ill.
If you add the significant index of false negatives up to 20% in screening (the strategy applied to a population to detect a disease in individuals without symptoms of that disease), where people are wrongly told that they do not have the infection, the scale of the problem is magnified.
These are the undercover propagators that will continue expelling the virus for up to 14 days, and this raises serious questions about the effectiveness of testing strategies or the use of detection tools such as temperature checking.
Pieces of evidence are beginning to be collected, mainly from many small and disparate studies.
The whole picture will be assembled as the quality and quantity of evidence expands and refines our understanding of SARS-CoV-2.
However, science has not yet informed doctors on the best way to manage their patients.
CT scan injuries determine what treatment is needed. A personalized decision based on clinical judgment is still required.
So as scientific understanding grows, I will apply Osler’s advice with renewed conviction: care for your patients with all five senses on high alert. They will teach you what you need to know.
*This article was published in The Conversation and reproduced here under the Creative Commons license. Click here to read the original English version.
John Kinnear He is Director of the School of Medicine at Anglia Ruskin University, UK.
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