Table 1 Potential mechanisms of kidney damage and treatment strategies in COVID-19

From: Kidney involvement in COVID-19 and rationale for extracorporeal therapies

PathwayaMechanism of kidney damageSuggested treatment strategy
Cytokine damage
Cytokine release syndromeDirect cytokine lesionCytokine removal using various approaches: direct haemoperfusion using a neutro-macroporous sorbent; plasma adsorption on resin after separation from whole blood; CKRT with hollow fibre filters with adsorptive properties; high-dose CKRT with MCO or HCO membranes
Increased cytokine generation owing to ECMO, invasive mechanical ventilation and/or CKRT
Haemophagocytic syndrome
Organ crosstalk
Cardiomyopathy and/or viral myocarditisCardiorenal syndrome type 1LVAD, arteriovenous ECMO
Alveolar damageRenal medullary hypoxiaVenovenous ECMO
High peak airway pressure and intra-abdominal hypertensionRenal compartment syndromeVenovenous ECMO, extracorporeal CO2 removal, CKRT
RhabdomyolysisTubular toxicityCKRT using a HCO or MCO membrane
Systemic effects
Positive fluid balanceRenal compartment syndromeContinuous ultrafiltration and diuretics
Endothelial damage, third-space fluid loss and hypotensionRenal hypoperfusionVasopressors and fluid expansion
RhabdomyolysisTubular toxicityCKRT using a HCO or MCO membrane
EndotoxinsSeptic AKIEndotoxin removal using polysterene fibres functionalized with polymyxin-B
  1. AKI, acute kidney injury; CKRT, continuous kidney replacement therapy; ECMO, extracorporeal membrane oxygenation; HCO, high cut-off; LVAD, left ventricular assist device; MCO, medium cut-off. aThe pathways and mechanisms are interconnected and treatment strategies will influence different aspects simultaneously.