Therapeutic plasma exchange in the treatment of COVID-19 induced cytokine storm: the first Moroccan experience

Introduction: COVID-19 induced cytokine storm is a well-documented phenomena that contributes significantly in the disease's evolution and prognosis. Therefore, therapies such as therapeutic plasma exchange, constitute a mainstay of therapeutic management especially for critically-ill patients.

Methods: We conducted a monocentric retrospective cohort study in the Resuscitation Department of the Mohammed VI University Hospital of Oujda-Morocco, to evaluate the efficiency of therapeutic plasma exchange on critically-ill COVID-19 patients over a 6 months period. We divided our patients into two groups: patients who received TPE (Therapeutic Plasma Exchange) sessions (TPE group) and patients who only benefited from the standard protocol treatment (non TPE group).

Results: Our study included a total of 165 patients, 34.5% of which benefited from TPE sessions. We observed an improvement of oxygenation parameters (SpO2 and PaO2/FiO2 ratio) and a progressive respiratory weaning, as well as a significant decrease of biomarkers indicative of inflammation (lymphocyte count, CRP (C Reactive Protein), IL-6, Ferritin) and coagulopathy (d-dimers, fibrinogen) in the TPE group after 5 consecutive TPE sessions. In comparison with the non-TPE group, The TPE-group patients had a shorter ICU (Intensive Care Unit) length of stay, required less frequently mechanical ventilation, and we more likely to be extubated. Furthermore, the TPE group had a lower mortality rate.

Discussion: Multiple studies have reported the safety and efficiency of therapeutic plasma exchange in the COVID-19 induced cytokine storm. Given the urgent character of the pandemic at the time, each center followed its own protocol in implementing plasma exchange.

Conclusion: Similar to the results reported in the literature, our study reports positive results after using TPE specifically in terms of respiratory weaning and an improvement of the cytokine storm biomarkers, and more importantly a lower mortality rate.