Peripheral biomarkers' panel for severe COVID-19 patients

It is widely reported in the literature that CD4, CD8 and total T cell count are significantly reduced in critically ill patients with COVID-19. Few weeks ago, we suggested natural killer (NK) cell count as a marker of severity in 34 hospitalized COVID-19 patients. On this topic, our research group firstly described a novel potential COVID19 severity marker, Krebs von den Lungen-6. This study aimed to investigate how a combination of COVID19 severity markers could be helpful in the clinical management of these patients. The combination of these validated, reproducible and non-expensive bioindicators showed a good accuracy in discriminating between severe and non-severe patients, suggesting a promising value of this approach in the early prediction of a more aggressive disease phenotype. Despite its monocentric design, our study confirms the reliable dysregulation of innate immune responses, particularly involving NK cells, and suggests that surveillance of a peripheral biomarkers' panel, including lymphocyte cell counts and KL-6, may be useful in the clinical management of severe COVID-19 patients.