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Dapsone Lowers Neutrophil to Lymphocyte Ratio and Mortality in COVID-19 Patients Admitted to the ICU
Badar Kanwar1, Asif Khattak2, Richard E Kast1
1IIAIGC Study Center, Burlington, VT 05408, USA.
Insights
Dapsone may improve outcomes for severe COVID-19 patients in the ICU by potentially lowering the neutrophil-to-lymphocyte ratio. Further controlled studies are needed to confirm dapsone
Area of Science:
- Critical Care Medicine
- Pharmacology
- Immunology
Background:
- Severe COVID-19 patients admitted to the ICU may receive dapsone as part of treatment.
- The efficacy of dapsone in severe COVID-19 is not well-established.
Purpose of the Study:
- To investigate the potential benefits of dapsone in severe COVID-19 patients.
- To explore laboratory markers that may indicate dapsone's mechanism of action.
Main Methods:
- Retrospective chart review of 29 ICU COVID-19 patients receiving dapsone and 30 not receiving dapsone.
- Analysis of laboratory findings, specifically the neutrophil-to-lymphocyte ratio.
Main Results:
- Mortality was lower in the dapsone group (30%) compared to the non-dapsone group (60%).
- The neutrophil-to-lymphocyte ratio decreased in 48% of patients receiving dapsone versus 30% not receiving it.
Conclusions:
- Dapsone may potentially lower the neutrophil-to-lymphocyte ratio in severe COVID-19 patients.
- This study's findings suggest a possible mechanism for dapsone's effect.
- A formal randomized controlled trial is warranted to confirm these preliminary observations.
Abstract:
Some physicians use dapsone as part of the standard treatment of severe COVID-19 patients entering the ICU, though some do not. To obtain an indication of whether dapsone is helping or not, we undertook a retrospective chart review of 29 consecutive ICU COVID-19 patients receiving dapsone and 30 not receiving dapsone. As we previously reported, of those given dapsone, 9/29 (30%) died, while of those not given dapsone, 18/30 (60%) died. We looked back on that data set to determine if there might be basic laboratory findings in these patients that might give an indication of a mechanism by which dapsone was acting. We found that the neutrophil-to-lymphocyte ratio decreased in 48% of those given dapsone and in 30% of those not given dapsone. We concluded that dapsone might be lowering that ratio. We then reviewed collected data on neutrophil related inflammation pathways on which dapsone might act as presented here. As this was not a controlled study, many variables prevent drawing any conclusions from this work; a formal, randomized controlled study of dapsone in severe COVID-19 is warranted.
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