Reactive oxygen species from neutrophils tied to severe COVID-19, sepsis
29 Jun 2022
In patients with severe COVID-19 or sepsis, high levels of neutrophils seem to be able to generate reactive oxygen species (ROS), which might contribute to disease pathology, a recent study has found.
The study included 15 COVID-19 patients admitted to the intensive care unit (ICU), 12 ICU patients with non-COVID-19 sepsis, and 18 healthy volunteers. A chemiluminescent assay was used to measure ROS production in blood samples, which was quantified as a LIT score. The median LIT score was 1,378 in COVID-19 patients, around nine times higher than that in controls (median, 153; p<0.05).
Moreover, LIT score was more than twice as high in the 10 COVID-19 patients on mechanical ventilation than comparators who did not need respiratory support (median, 2,020 vs 916; p=0.02), suggesting higher ROS production in the former group.
The researchers found a strong and significant correlation between median LIT scores and both white blood cell count (Spearman’s rho, 0.73; p=0.003) and neutrophil count (Spearman’s rho, 0.80; p=0.0004).
ROS production was similarly elevated in non-COVID-19 sepsis patients, who had a median LIT score of 2,120, around 14 times higher than in controls. As with COVID-19 patients, LIT correlated significantly with neutrophil counts (R, 0.76; p=0.009).
“Our findings pave the way for a new assessment of cellular function as a rapid point-of-care test that may help to monitor disease progression,” the researchers said. “Furthermore, this may also hold potential for guiding the introduction of immunomodulatory therapies to optimize innate cell function and improve clinical outcome.”