Blood test could identify severity of SARS-CoV-2 infections, researchers say
A blood test at the time of diagnosis can predict the severity of COVID-19-related illness and a patient’s risk for death, according to a small study published in PLoS One.
Robert A. Nagourney, MD, the medical and laboratory director at Nagourney Cancer Institute in Irvine, California, and colleagues conducted a cross-sectional, observational study of 113 participants, comparing plasma from 82 people with confirmed COVID-19 against 31 controls.
According to the authors, the analysis revealed changes in the concentrations of glutamate, valeryl-carnitine and the ratios of kynurenine/tryptophan to citrulline/ornithine among participants with COVID-19, which “may serve as predictors of disease severity.”
Nagourney said the idea for the study came from his past work.
“I became very interested in metabolism and cancer, and we published extensively on metabolic features of cancer,” Nagourney told Healio. “But when we began to do these studies over the years, I said, it seems to me that it's not just cancer, it's metabolic syndrome, diabetes, cardiovascular disease, dementia, multiple sclerosis — these are all measurable metabolically.”
Nagourney said it was about a year and a half ago when he had the idea to apply this theory to COVID-19.
Among the 113 participants in the trial, the mean age was 48.6 years, 51% were male and 75% were either overweight or obese and had a high rate of comorbidities.
Based on WHO’s classification of COVID-19 severity, 20 participants with COVID-19 were categorized with mild COVID-19, 32 had moderate disease and the remaining 30 had severe cases.
“It's amazing how quickly we got it done,” Nagourney told Healio. “Because, from concept to publication, it was 1 year. I don't think I've ever heard such a thing before. But it was brilliant, a brilliant example of a really smartly thought scientific test of hypothesis.”
According to Nagourney, this was just a pilot study. Going into it, the researchers were unsure if their hypothesis would be proven true or not, he said. Therefore, an at-home test or one for commercial use based on the finding would not be feasible in the near future.
“What we have been able to do is refine the most discriminating measures down to a handful of metabolites and ratios,” Nagourney said. “I don't want to overstate this. It's possible that we could refine this down to a collection of specific metabolites that one might introduce on a different platform, but right now, my mass spectrometer is a pretty delicate instrumentation. But is it possible that we could identify a collection of discriminants that might be converted into some sort of home test? I would say it’s speculatively possible.”