Protein found in blood can predict which Covid-19 patients may need breathing support, new study shows
A protein found in the blood can predict which coronavirus patients are likely to develop a severe infection, according to a new study.
Monitoring levels of this protein called suPAR might help in diagnosis and disease management. It could inform doctors which patients might need breathing support from ventilators at later stages.
Higher levels could indicate breathing difficulties or respiratory failure. "This is the first report in the world to show that suPAR is elevated in Covid-19 and is predictive." Dr Jochen Reiser and Dr Ralph C Brown, from the Chicago-based Rush University Medical Center, said in a statement.
Some researchers suggest that SuPAR, which is present in lung cells and other cells that fight infection, could signal an active immune system.
The study carried out by the Chicago-based Rush University Medical Center looked at 15 patients at Rush hospital. The researchers measured the protein levels in all the patients and monitored them throughout their symptoms. They then compared these results with 57 others at the University of Athens Medical School in Greece.
Patients with protein levels at six nanograms per milliliter or higher developed severe respiratory failure sooner than the others. Nearly 86% of the patients with such levels required mechanical ventilation or a CPAP machine for support. The latter is typically used to treat patients experiencing breathing problems during sleep by keeping the airways open.
They added that patients with higher levels of the protein might go on to have failed lungs. And in a short span, they relied on ventilators for support.
"There is a body of literature that suPAR is associated with poor outcomes from acute respiratory distress syndrome (a condition in many patients with severe COVID-19) and poor lung functioning in critically ill patients," Reiser said.
These findings might help doctors treat patients effectively. "If we measure suPAR as part of diagnosing Covid-19, we may know whom to watch more and whom to send home. Plasma suPAR levels give us a window into the course of the disease, allowing for improved monitoring and applying new and supportive treatments early," he added.
Their levels are linked to organ damage in various diseases. Reiser's studies have linked the protein to kidney injury — a sudden decline in kidney function that can be a severe side effect of general medical procedures.
The new coronavirus is known to hurt the kidneys of some patients. Higher levels of suPAR may help predict the condition, the researchers believe. They also suspect the protein could be involved in the disease.
Reiser and his colleagues will now investigate the link between the Covid-19, suPAR, and kidney disease. "Our research on suPAR and Covid-19 associated lung injury is based on small sample size, and we will need more data, but the findings support a concept that suPAR is harmful in Covid-19. It may, therefore, play a prognostic and a causal role in Covid-19 associated kidney disease," Reiser said.
The study is published in the Journal of Critical Care.