Cytokine storm syndrome (
CSS MESHD) has been documented in
coronavirus disease 2019 MESHD (
COVID-19 MESHD) since the first reports of this disease. In the absence of vaccines or direct therapy for
COVID-19 MESHD, extracorporeal blood treatment (EBT) could represent an option for the removal of cytokines and may be beneficial to improve the clinical outcome of
critically ill MESHD patients. Intermittent haemodialysis (
IHD MESHD), using high flux (HF) or high cut-off membranes, and continuous renal replacement therapy (CRRT) could be used for blood purification in
COVID-19 MESHD patients with CSS. To the best of our knowledge, cytokine kinetics during and after different types of EBT on
COVID-19 MESHD patients have never been studied. In this study, we describe cytokine variation and removal during and after
IHD MESHD and CRRT in
COVID-19 MESHD patients with
acute kidney injury MESHD (
AKI MESHD). Methods: Patients with
COVID-19 MESHD-related
AKI MESHD according to
Kidney Disease MESHD Improving Global Outcomes (KDIGO) criteria and admitted at Intensive Care Unit (ICU) were studied. Blood samples were collected at the start and end of both
IHD MESHD using HF membranes (10 patients) and continuous venovenous haemodiafiltration (CVVHDF: 10 patients) in two sessions for measuring 13 different plasma interleukins and calculating the cytokine removal rate. Results: We evaluated cytokine removal in patients with
COVID-19 MESHD-related
AKI MESHD undergoing either prolonged
IHD MESHD (10 patients) or CRRT (CVVHDF: 10 patients). There was no difference between the
IHD MESHD and CVVHDF groups regarding mechanical ventilation, vasoactive drug use, age or prognostic scores. Patients treated by CRRT presented higher levels of
IL-2 HGNC and
IL-8 HGNC than patients treated by prolonged IHD at the start of dialysis. Cytokine removal ranged from 9–78%. Patients treated by CRRT presented higher cytokine removal rates than those treated by prolonged IHD for
IL-2 HGNC, IL-6 IL-8,
IP-10 HGNC and
TNF HGNC. The removal rates of
IL-4 HGNC,
IL-10 HGNC,
IL-1β HGNC,
IL-17A HGNC,
IFN HGNC,
MCP-1 HGNC and free active
TGF-B1 HGNC were similar in the two groups. After one session of CVVHDF (24 h) the
IL-2 HGNC and
IL-1β HGNC levels did not vary significantly, whereas
IL-4 HGNC,
IL-6 HGNC,
IL-8 HGNC,
IL-10 HGNC,
IL-17A HGNC,
TNF HGNC,
IFN HGNC,
IP-10 HGNC,
MCP-1 HGNC, IL-12p70 and free active
TGF-B1 HGNC decreased by 33.8–76%, and this decrease was maintained over the next 24 h. In the prolonged IHD groups,
IL-2 HGNC,
IL-6 HGNC,
TNF HGNC,
IP-10 HGNC and
IL-1β HGNC levels did not decrease significantly whereas
IL-4 HGNC,
IL-8 HGNC,
IL-10 HGNC,
IL-17A HGNC,
IFN HGNC,
MCP-1 HGNC, IL-12p70 and free active
TGF-B1 HGNC decreased by 21.8–72%. However, all cytokine levels returned to their initial values after 24 h, despite their removal. Conclusions: Cytokine removal is lower using prolonged
IHD MESHD with HF membranes than by using CVVHDF, and
IHD MESHD allows a transient and selective decrease in cytokines that can be correlated with mortality during CSS-related
COVID-19 MESHD.