Abstract
Purpose: A prompt and effective immune response is required for clearance of pathogens but exaggerated states of inflammation can cause extensive collateral damage to the host. We have previously used a rapid near-patient assay that measures the functional capacity of neutrophils to produce reactive oxygen species (ROS) to show that values are elevated in patients with severe COVID-19 or sepsis. Here, we assess the utility of longitudinal ROS measurements to monitor and predict mortality outcome for patients with COVID-19 infection being treated in an ICU setting.
Methods: We used the Leukocyte ImmunoTest™ (LIT™) to quantify neutrophil ROS release using a small volume (10 µL) of capillary blood in a portable, rapid (10-min) format.
Results: ROS values (LIT score) and ROS levels assessed in relation to neutrophil count (LIT/N) were both markedly elevated in the patient group. Furthermore, these correlated strongly with peripheral neutrophil count and CRP value. Serial measurement of neutrophil or CRP values were not able to reliably predict mortality within the study. In contrast, LIT and LIT/N values started to decline at 7 and 5 days, respectively, in patients who survived ICU admission and this increment increased further thereafter.
Conclusions: This study raises the possibility of LIT and LIT/N to be used as a predictive clinical tool for patients with severe COVID-19 and argues for its assessment to inform on prognosis, and potentially guide treatment pathways, in other disorders associated with neutrophil activation.
Take-home message: A longitudinal study of 44 severe COVID-19 patients in the ICU of a leading teaching hospital has demonstrated the prognostic potential of a rapid bedside assay of neutrophil-derived reactive oxygen species (ROS). Assessment of changes in ROS production, as measured using the Leukocyte ImmunoTest™, shows that ROS production generally declined back to normal levels for patients who survived, but remained elevated for those patients who did not survive.
Methods: We used the Leukocyte ImmunoTest™ (LIT™) to quantify neutrophil ROS release using a small volume (10 µL) of capillary blood in a portable, rapid (10-min) format.
Results: ROS values (LIT score) and ROS levels assessed in relation to neutrophil count (LIT/N) were both markedly elevated in the patient group. Furthermore, these correlated strongly with peripheral neutrophil count and CRP value. Serial measurement of neutrophil or CRP values were not able to reliably predict mortality within the study. In contrast, LIT and LIT/N values started to decline at 7 and 5 days, respectively, in patients who survived ICU admission and this increment increased further thereafter.
Conclusions: This study raises the possibility of LIT and LIT/N to be used as a predictive clinical tool for patients with severe COVID-19 and argues for its assessment to inform on prognosis, and potentially guide treatment pathways, in other disorders associated with neutrophil activation.
Take-home message: A longitudinal study of 44 severe COVID-19 patients in the ICU of a leading teaching hospital has demonstrated the prognostic potential of a rapid bedside assay of neutrophil-derived reactive oxygen species (ROS). Assessment of changes in ROS production, as measured using the Leukocyte ImmunoTest™, shows that ROS production generally declined back to normal levels for patients who survived, but remained elevated for those patients who did not survive.
| Original language | English |
|---|---|
| Article number | 69 |
| Number of pages | 12 |
| Journal | Intensive Care Medicine Experimental |
| Volume | 11 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 6 Oct 2023 |
Bibliographical note
Funding:The research was funded in part by Innovate UK, Project No. 56969, Project title: COVID-19: Development of novel algorithm-driven digital platform for assessing the Leukocyte ImmunoTest(TM) as a clinical parameter in monitoring vulnerability to coronavirus. In addition, this project has indirectly received funding from the European Union’s Horizon 2020 research and innovation programme under project INNO4COV-19 (Grant agreement No 101016203).
Copyright:
© 2023. European Society of Intensive Care Medicine and Springer Nature Switzerland AG.
Keywords
- Reactive oxygen species (ROS)
- COVID-19
- Leukocyte ImmunoTest
- Neutrophil