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Like ‘frosted glass’ in the lungs Russian Health Ministry pulmonologist explains challenges of COVID-19 testing and how Moscow's doctors are managing to diagnose patients

Source: Meduza
Artyom Geodakyan / TASS / Vida Press

On April 9, Moscow’s coronavirus task force indicated that the majority of the city's pneumonia cases are related to COVID-19. A new coronavirus clinical committee subsequently advised against using separate hospitals to treat patients with pneumonia and COVID-19, and recommended making diagnoses based on clinical information and CT scan results without waiting for coronavirus test results (which have turned out to be unreliable). Meduza asked Sergey Adveev, the Russian Health Ministry's chief visiting pulmonologist, why tests aren’t working, what distinguishes coronavirus pneumonia from other kinds of pneumonia, and how Russian doctors are handling patients presumed to have coronavirus.  

Some regions of Russia are now reporting a surge in community-acquired pneumonia cases. This could be related to what exactly?

What makes you think there’s a surge?

There are reports from Saratov and Crimea of roughly 70-percent increases of such cases.

That information is incorrect. After all, we’re better acquainted with the relevant statistics on community-acquired pneumonia. There is no surge or increase in the cases of community-acquired pneumonia. All indicators are at the same levels as they were last year, and in some places it's even 20-percent less than last year's average annual figures. There’s always some seasonality with pneumonia, with an increase in cases in the winter months. In April, there’s a small number of cases. We’re not seeing outbreaks, surges, or increases virtually anywhere in any region. 

But there’s a hospital in Bashkortostan that’s been placed under quarantine.

There was coronavirus there. 

But initially they had many patients with pneumonia of uncertain origin.  

I can’t make a judgement about that now, but it quickly emerged that they were dealing with an outbreak of coronavirus infections. I think that happened in a short period of time. 

How likely is it that in some “underdeveloped” regions doctors won’t be able to distinguish coronavirus-infected pneumonia from regular pneumonia?

The risk is small. They have CT scans in most regions, including in central district hospitals. This is not a rare piece of technology in Russian medicine. In addition to CT, there are very simple tests: a complete blood count [CBC], and a basic metabolic panel [BMP] blood test. Today we know the changes reflected in these tests that are characteristic of coronavirus-infected pneumonia. 

How does regular pneumonia differ from coronavirus-infected pneumonia?

My colleagues and I are now working exclusively with patients who have coronavirus. There are 300 patients in my clinic and they all have the same diagnosis. Any pneumonia is clearly visible via CT. There are big differences even between simple bacterial pneumonia and viral pneumonia. And there are signs that allow us to say with confidence that we’re in fact looking at a coronavirus infection when performing a CT scan. Pockets of coronavirus pneumonia look like so-called frosted glass. Coronavirus-infected pneumonia is distributed throughout the lungs differently and affects a different part of the lungs. As a rule, it’s bilateral pneumonia [occurs in both lungs], and most often—especially in the early stages—it manifests in the lower parts [of the lungs]. The localization is peripheral, meaning further out from the heart, toward the rib cage. A combination of these indicators is typical of coronavirus-infected pneumonia. That is to say, with CT we can detect coronavirus-infected pneumonia with high accuracy.

Are CT images more accurate than the tests?

That would be comparing apples to oranges. Tests are required and laboratory confirmation is desirable in all cases. 

You talked about the accuracy of coronavirus testing at a recent medical conference. According to your comments then, tests are about 70-percent accurate. The Federal Service for Consumer Rights Protection and Human Welfare [Rospotrebnadzor] says their test systems are 98-percent accurate. 

There’s a simple explanation for this. There are no issues with the tests, nor with the accuracy of the tests, but with the disease itself. The situation is as follows: In order for the test to be sensitive, we have to catch a particle of the virus in human cells — this is why we perform a swab test. But if we perform a swab test at a moment when cells are free of the virus, we don’t find anything. This can happen in the early stages of infection, and the particular spot where the swab is collected from plays a role. The probability of finding the virus and getting a positive result is higher when swabbing the nose than the oropharynx. This is nothing new — it’s the same situation all over the world. Today the most accessible test for us, and in fact the only one so far, is a PCR-based test, where we’re looking for an RNA particle in real time. It can be difficult to detect the virus, not because the tests don’t work, but because there might not be a particle where we’ve swabbed. 

But we still see the typical clinical picture, the typical changes according to the CT scan, and the typical blood work results. Such a case would be designated “probable COVID-19.” This sort of situation is reflected in the Health Ministry's clinical recommendations.

Some of your colleagues say that a blood test can also be indicative of coronavirus. Is that so?

You can make an assumption that there is coronavirus-infected pneumonia based on a blood test. For example, by looking at lymphocytes [a type of white blood cell]. In coronavirus-infected pneumonia, few lymphocytes are present. 

How long does it take to treat coronavirus-infected pneumonia?

On average, a patient with pneumonia is hospitalized for 8-10 days, while a patient with coronavirus is typically in the hospital for 15. So longer than a week. Coronavirus-infected pneumonia is not treated with antibiotics like regular pneumonia, and it can progress rapidly.

Tell us, how are patients with pneumonia being hospitalized now?

Now the situation in Moscow — I think all over Russia you’ll see the same thing — is that they’re repurposing buildings to treat coronavirus infections. Today in Moscow [on April 16], there are 30 hospitals treating COVID-19 patients.

There are patients with symptoms of an acute upper-respiratory-tract infection, but until we test them we don’t know if they’re infected. On the other hand, if a patient has been in contact with someone infected with coronavirus, they’re most likely infected, too. The patient calls a doctor, who either recommends they be hospitalized or they stay at home. Staying home means self-isolation and quarantine. If their condition is serious, they’re sent to one of the coronavirus-designated facilities. And various scenarios could play out there. In Moscow, the patient is tested, medical staff administer a CT scan, they determine his oxygen saturation levels, and they see a doctor, who based on these indicators, decides where the patient should go: to a regular hospital bed, the intensive care unit, or perhaps, home. 

And not all pneumonia patients will be hospitalized in coronavirus-designated facilities?

Of course not, because not all patients have viral pneumonia. Bacterial pneumonia still exists, and it’s important to remember that. Bacterial pneumonia is not contagious. Pneumonia itself is not transmitted from person to person. 

If a patient who has regular, non-coronavirus pneumonia is hospitalized in a coronavirus designated hospital, what are the chances they will be infected?

The chances are high, so we’re doing everything we can to avoid this. A patient who might have non-coronavirus pneumonia will most likely be taken to a non-coronavirus hospital, thanks to paramedic workers. 

You said in an interview that in some cases coronavirus-infected pneumonia can be asymptomatic, while in others, it can lead to total lung failure. How can this be?

If it’s an asymptomatic case, then it’s unlikely to lead to total lung damage. Mild cases of pneumonia can occur without symptoms. This happens quite often with coronavirus-infected pneumonia.

Do asymptomatic cases threaten a patient’s health?

How can it pose a threat to their health if it’s such a mild case that it could go unnoticed? You just go about your business, you’re infected, but don’t feel anything. This kind of pneumonia most often doesn’t pose a threat to anyone. Scenarios can play out differently, but the unfavorable cases are those where patients are experiencing problems and have symptoms and complaints. Shortness of breath in particular is one of the first symptoms that signals the severity of the condition. 

Lots of people are concerned that patients with mild cases are being sent home for treatment, where they go without a doctor's supervision.

Those who are at risk are not sent home. They are only discharging those who don't need hospital care. Many patients can do without it. For the patient, this is a favorable situation: they’re at home, isolated, and getting treatment. In the vast majority of people, the virus occurs in asymptomatic or mild-symptomatic form, but these patients are still contagious, and thus present a threat to others.

Interview by Anastasia Yakoreva

Translation by Rob Viano