Rapid blood tests identify COVID-19 patients at high risk of severe illness

One of the most annoying aspects of the COVID-19 pandemic is which newly admitted patients develop serious illness, including complications requiring respiratory tube insertion, renal dialysis, or other intensive care. Is unpredictable by doctors. Knowledge of the patient’s age and underlying medical condition can help predict such outcomes, but is still surprising when young, seemingly healthy patients suffer from serious complications that can lead to death. There is.

Currently, scientists at Washington University in St. Louis School of Medicine can predict whether patients with COVID-19 are at greatest risk of serious complications within a day of admission with a relatively simple and rapid blood test. Was shown. death.

Study published on January 14 JCI InsightNearly 100 newly admitted patients with COVID-19 were involved.

Blood tests measure the level of mitochondrial DNA, a unique type of DNA molecule that usually resides within a cell’s energy plant. Mitochondrial DNA, which spills from cells into the bloodstream, indicates that certain types of severe cell death are occurring in the body.

“Due to the lack of many treatments, such as monoclonal antibodies, doctors need better tools to assess the condition of COVID-19 patients as soon as possible, and without intensive treatment. But some patients improve. ”Co-chief author Andrew E. Gelman, PhD, Jacqueline G., and William E. Maritz have awarded the Chairs of Immunology and Oncology in the Department of Surgery.

“There are many things we still don’t understand about this disease,” he added. “In particular, we need to understand why some patients fall into this spiral of hyperinflammatory death, regardless of age or underlying health. Our study shows that mitochondrial DNA is the cause of this spiral. It suggests that it may be one. It is an inflammatory molecule that is released in itself. “

Researchers may find this test useful not only as a way to predict the severity of the disease, but also as a tool for better designing clinical trials, for example, benefiting from specific clinical trial treatments. He said he could identify potential patients. They also said they would like to assess whether the test can serve as a way to monitor the effectiveness of new treatments. Perhaps effective treatment will lower mitochondrial DNA levels.

“To verify what we found in this study, a larger study is needed, but in the first 24 hours of hospitalization, dialysis, intubation, or medication to prevent the patient’s blood pressure from dropping too low. If we can determine if we need it, it can change the way patients are triaged and the way they manage patients much earlier in the course of their illness, “said Hrishikesh S., co-chief author and assistant professor of medicine. Dr. Kulkarni said.

Researchers, including co-lead authors Davide Scozzi, MD, PhD, staff scientists, and postdoctoral researchers Marlene Cano and PhD, evaluated 97 patients with COVID-19 and measured mitochondrial DNA levels at Burns Jewish Hospital. .. The first day of their hospitalization. They found that mitochondrial DNA levels were much higher in patients who were eventually admitted to the ICU, intubated, or died. Researchers have found that the association is held independently of the patient’s age, gender, and underlying health status.

On average, mitochondrial DNA levels were about 10-fold higher in patients with COVID-19 who developed severe pulmonary dysfunction or eventually died. High-level individuals were almost six times more likely to be intubated, three times more likely to be hospitalized in the ICU, and nearly twice as likely to die than those with lower levels.

In addition, the test predicted results equal to or better than the existing markers of inflammation currently measured in patients admitted with COVID-19. According to researchers, most other inflammatory markers measured in patients with COVID-19 are common markers of systemic inflammation rather than cell death-specific inflammation.

“The virus can cause a type of tissue damage called necrosis, which is a violent inflammatory response to the infection,” German said. “The cells break down and release content containing mitochondrial DNA that causes inflammation in itself. In COVID-19 patients, there is anecdotal evidence of this type of cell and tissue damage in the lungs, heart, and kidneys. I think it is possible. Measurement of mitochondrial DNA in the blood can be an early sign of this type of cell death in important organs. “

The researchers also emphasized that the test can be performed quickly and easily in most hospital settings because it uses the same machine that handles the standard PCR test for COVID-19. The method they developed allows direct quantification of mitochondrial DNA levels in the blood. The technique returned results in less than an hour, without the need for intermediate steps to extract DNA from the blood.

Scientists need to verify that the trials are accurate in large multicenter trials before applying for approval from the Food and Drug Administration (FDA). They have plans to extend their research to more sites.

This study used samples from the School of Medicine’s COVID-19 bio-repository developed by School of Medicine assistant professors Jane O’Halloran, MD, and PhD. Dr. Charles Goss, biostatistics instructor. Philip Mad, MD, PhD, Associate Professor of Emergency Medicine.