Although mechanisms explaining previous findings are not yet fully understood, it has been reported that there was a decrease in plasma rennin concentrations in patients diagnosed with acute on chronic liver failure with renal impairment that were treated with MARS. Likewise, other studies have suggested some efficacy for MARS in the treatment of hepatorenal syndrome.[65][66][67] However, other references have been published that do not show efficacy in the treatment of these types of patients with MARS therapy. Khuroo et al.[68] published a metaanalysis based in 4 small RCT’s and 2 non RCT’s in patients diagnosed with ACLF, concluding that MARS therapy would not bring any significant increment on survival compared with SMT.