Study detects hidden lung lesions in Covid-19

Some people with long-term Covid may experience hidden lung damage, a pilot study in the UK suggests.

This would help explain the shortness of breath that some patients report experiencing, even after they have recovered from the initial infection.

Scientists used a new method to detect lung lesions that are not identified in routine examinations.

The team evaluated 11 individuals who did not need hospital care when they first had Covid, but even after they recovered, they reported being short of breath for a prolonged time.

Larger and more detailed research on this topic is under way to confirm the initial findings.

The recently released work builds on a previous study, which looked at people who were admitted to the hospital with Covid.

The researchers say the findings shed some light on why shortness of breath is so common during and after infection with the coronavirus — although the reasons for experiencing this discomfort are many and complex.

The term “Long Covid” refers to a set of symptoms that continue for several weeks after the initial painting and cannot be explained by another cause.

The Oxygen Journey

The team, which brought together experts from the universities of Oxford, Birmingham, Cardiff and Manchester, compared the results of an imaging test using a gas called xenon and other lung function tests in three groups of people.

The first group consisted of 11 individuals with long-term Covid and shortness of breath who did not need to be hospitalized during the infection.

The second brought together 12 volunteers who were hospitalized for Covid, but did not have these long-lasting symptoms.

Finally, 13 healthy people were also included so that the results could be compared.

Using the new approach, developed by the University of Sheffield, also in the UK, all participants inhaled xenon gas while undergoing an imaging test called MRI.

The gas behaves very similarly to oxygen, but can be visually tracked during the scan, so the scientists could clearly “see” how it moved from the lungs into the bloodstream — a crucial step in transporting oxygen around the body. .

The researchers found that for most people with long-term Covid, the transfer of xenon from the lungs to the blood was less effective than what was seen in healthy individuals.

People who were admitted to the hospital because of Covid also had a similar problem in this transition from gas from the lungs to the blood circulation.

Pulmonologist Emily Fraser, the study’s lead author, says it’s frustrating to see people seeking medical help without being able to explain very well why they’re out of breath. To make matters worse, most of the time, x-rays and CT scans do not detect these lung abnormalities.

“This is important research and I really hope it helps to shed more light on this issue.”

She added: “It’s important for people to know that rehabilitation strategies and breathing training can be really helpful.”

“When we see people out of breath, we understand the problem and we can intervene better.”

Radiologist and professor Fergus Gleeson, co-author of the work, stated: “There are now important questions to be answered, such as how many patients with Covid long will have these tests changed, the practical significance of what is detected, the cause of this and the long-term consequences. .”

“Once we understand the mechanisms that lead to these symptoms, we can develop more effective treatments.”

It is worth mentioning that the study was published in pre-print format and has not yet been reviewed by independent experts or published in a scientific journal.