New Delhi: Secondary bacterial pneumonia that does not resolve was a key driver of death in patients with COVID-19, according to a study which suggests that the viral disease does not cause a “cytokine storm” so often believed to cause mortality. The researchers found that secondary bacterial infection of the lung (pneumonia) was extremely common in patients with COVID-19, affecting almost half the patients who required support from mechanical ventilation. It may even exceed death rates from the SARS-CoV-2 viral infection itself, they said.
By applying machine learning, a form of artificial intelligence (AI), to medical record data, scientists at Northwestern University Feinberg School of Medicine in the US found evidence that COVID-19 does not cause a “cytokine storm,” severe immune reaction in which the body releases too many cytokines into the blood too quickly.
Cytokines play an important role in normal immune responses, but having a large amount of them released in the body all at once can be harmful. Study senior author Benjamin Singer, an associate professor at Northwestern University Feinberg School of Medicine, US, said,
Our study highlights the importance of preventing, looking for and aggressively treating secondary bacterial pneumonia in critically ill patients with severe pneumonia, including those with COVID-19. School of Medicine, US.
The study, recently published in the Journal of Clinical Investigation, found nearly half of patients with COVID-19 develop a secondary ventilator-associated bacterial pneumonia. Mr. Singer said,
Those who were cured of their secondary pneumonia were likely to live, while those whose pneumonia did not resolve were more likely to die. Our data suggested that the mortality related to the virus itself is relatively low, but other things that happen during the ICU stay, like secondary bacterial pneumonia, offset that.
The findings also negate the cytokine storm theory, said Singer, also the Lawrence Hicks Professor of Pulmonary Medicine at Feinberg.
The term ‘cytokine storm’ means an overwhelming inflammation that drives organ failure in your lungs, your kidneys, your brain and other organs,” Singer said. If that were true, if cytokine storm were underlying the long length of stay we see in patients with COVID-19, we would expect to see frequent transitions to states that are characterized by multi-organ failure. That’s not what we saw.
The study analyzed 585 patients in the intensive care unit (ICU) at Northwestern Memorial Hospital with severe pneumonia and respiratory failure, 190 of whom had COVID-19. The scientists developed a new machine learning approach called CarpeDiem, which groups similar ICU patient-days into clinical states based on electronic health record data.
This novel approach, which is based on the concept of daily rounds by the ICU team, allowed them to ask how complications like bacterial pneumonia impacted the course of illness. These patients or their surrogates consented to enroll in the Successful Clinical Response to Pneumonia Therapy (SCRIPT) study, an observational trial to identify new biomarkers and therapies for patients with severe pneumonia.
As part of SCRIPT, an expert panel of ICU physicians used state-of-the-art analysis of lung samples collected as part of clinical care to diagnose and adjudicate the outcomes of secondary pneumonia events. Study co-first author Catherine Gao, an instructor in pulmonary and critical care medicine at Feinberg and a Northwestern Medicine physician.
The application of machine learning and artificial intelligence to clinical data can be used to develop better ways to treat diseases like COVID-19 and to assist ICU physicians managing these patients.
Study co-author Richard Wunderink, who leads the Successful Clinical Response in Pneumonia Therapy Systems Biology Center at Northwestern, said,
The importance of bacterial superinfection of the lung as a contributor to death in patients with COVID-19 has been underappreciated because most centres have not looked for it or only look at outcomes in terms of presence or absence of bacterial superinfection, not whether treatment is successful or not.
(This story has not been edited by NDTV staff and is published from a syndicated feed.)
NDTV – Dettol have been working towards a clean and healthy India since 2014 via the Banega Swachh India initiative, which is helmed by Campaign Ambassador Amitabh Bachchan. The campaign aims to highlight the inter-dependency of humans and the environment, and of humans on one another with the focus on One Health, One Planet, One Future – Leaving No One Behind. It stresses on the need to take care of, and consider, everyone’s health in India – especially vulnerable communities – the LGBTQ population, indigenous people, India’s different tribes, ethnic and linguistic minorities, people with disabilities, migrants, geographically remote populations, gender and sexual minorities. In wake of the current COVID-19 pandemic, the need for WASH (Water, Sanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign will continue to raise awareness on the same along with focussing on the importance of nutrition and healthcare for women and children, fight malnutrition, mental wellbeing, self care, science and health, adolescent health & gender awareness. Along with the health of people, the campaign has realised the need to also take care of the health of the eco-system. Our environment is fragile due to human activity, which is not only over-exploiting available resources, but also generating immense pollution as a result of using and extracting those resources. The imbalance has also led to immense biodiversity loss that has caused one of the biggest threats to human survival – climate change. It has now been described as a “code red for humanity.” The campaign will continue to cover issues like air pollution, waste management, plastic ban, manual scavenging and sanitation workers and menstrual hygiene. Banega Swasth India will also be taking forward the dream of Swasth Bharat, the campaign feels that only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and the country can become a Swasth or healthy India.