Is Cytokine Storm the Key Factor in the Death Rate of COVID-19 Patients
Unresolved secondary bacterial infection of the lung (pneumonia) was the key driver of death in patients with COVID-19. It may even exceed death rates from the viral infection itself. This finding was found by scientists at Northwestern University Feinberg School of Medicine.
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 ().
‘Machine learning links unresolved secondary pneumonia (bacterial lung infection) to mortality in patients with severe COVID-19.’
By applying machine learning to medical record data, scientists found evidence that COVID-19 does not cause a "cytokine storm," so often believed to cause death. The finding was recently published in the Journal of Clinical Investigation.
Preventing Mortality in COVID-19 Patients: Which Thing to Target?
"The term �cytokine storm' means an overwhelming inflammation that drives organ failure in your lungs, your kidneys, your brain, and other organs (). 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 is not what happening.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 the illness. As part of the study, an expert panel 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.
It is Important Treat Secondary Bacterial Lung Infection in COVID-19 Patients
The importance of bacterial superinfection of the lung as a contributor to death in patients with COVID-19 has been underappreciated because most centers have not looked for it or only look at outcomes in terms of the presence or absence of bacterial superinfection, not whether treatment is successful or not ().The next step in the research will be to use molecular data from the study samples and integrate it with machine learning approaches to understand why some patients go on to be cured of pneumonia and some do not.
Investigators also want to expand the technique to larger datasets and use the model to make predictions that can be brought back to the bedside to improve the care of critically ill patients.
Those who were cured of their secondary pneumonia were likely to live, while those whose pneumonia did not resolve were more likely to die. These data also 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.
References:
- COVID-19 infection: an overview on cytokine storm and related interventions - (https:virologyj.biomedcentral.com/articles/10.1186/s12985-022-01814-1)
- Impact of cytokine storm on severity of COVID-19 disease in a private hospital in West Jakarta prior to vaccination - (https:journals.plos.org/plosone/article?id=10.1371/journal.pone.0262438)
- Machine learning links unresolving secondary pneumonia to mortality in patients with severe pneumonia, including COVID-19 - (https:www.jci.org/articles/view/170682)
Source: Eurekalert