A comparison among three different apheretic techniques for treatment of hyperbilirubinemia.

Liver failure is associated to high mortality due to the accumulation of protein-bound metabolites, such as bilirubin, not removed by conventional hemodialysis. Different methods can efficiently remove them, such as the molecular adsorbent recirculating system (MARS), plasma exchange (PEX), and bilirubin or plasma adsorption perfusion (PAP). No direct comparison exists between MARS, PEX and PAP, and current guidelines do not specify which method (and when) to use. We have retrospectively evaluated MARS, PEX and PAP in their effectiveness in lowering plasma bilirubin concentration, and their effects on liver and kidney function. A total of 98 patients have been recruited, which comprised 68 patients treated with PAP (177 sessions), 16 patients with PEX (41 sessions) and 11 patients with MARS (21 sessions). Bilirubin, creatinine, liver enzymes were analyzed before and after the first treatment with each technique. The three methods did not differ for bilirubin lowering efficiency, with MARS showing only slightly less effective reductions. Finally, the three techniques did not differ in the amount of change of cholinesterase, but a lower reduction in AST was found using PAP. Our retrospective observation is one of the largest case series of hepatic failure treated with bilirubin absorption. The choice of the technique cannot be based on the desired reduction in bilirubin concentration. Based on costs and duration of treatment, we suggest that PAP could be considered as a first-line approach. In case of kidney involvement, MARS remains a valuable option.

[Apheresis Techniques for the Treatment of Hyperbilirubinemia in the Nephrology Unit].

Therapeutic apheresis is an important hematological and nephrological method for conditions with altered plasma composition. It is also indicated for the removal of protein-bound molecules, such as bilirubin. Several techniques can remove these compounds, such as the extracorporeal circulation molecular adsorption system (MARS), plasma exchange (PEX), and plasma adsorption and perfusion (PAP). Here we report our experience in the comparison between MARS, PEX and PAP, since current guidelines do not specify which method is the most appropriate and under which circumstances it should be used. The choice of technique cannot be based on the desired plasma bilirubin concentration, since these three techniques show similar results with a similar final outcome (exitus). In fact, PAP, PEX and MARS significantly reduce bilirubin levels, but the degree of reduction is not different among the three. Furthermore, the three techniques do not differ in the rate of cholinesterase change, while less reduction of liver transaminases was found by using PAP. MARS should be preferred in the case of renal involvement (hepatorenal syndrome with hyperbilirubinemia). PAP has the advantage of being simple and inexpensive. PEX remains an option when emergency PAP is not available, but the risk of using blood products (plasma and albumin) must be considered.

[An overview on acute kidney injury in COVID-19].

SARS-CoV-2 infection is responsible for the coronavirus disease 2019 (COVID-19). In the complex scenario of COVID-19, it is also possible to find patients with renal damage. The pathogenesis is multifactorial and not unique, and the clinical presentation may include urinary alterations, such as proteinuria and hematuria, accompanied with reduced renal function, or not. Acute kidney injury (AKI) is not uncommon, especially among critically ill patients hospitalized in intensive care unit. AKI is a negative prognostic factor and is associated with high in-hospital mortality. An early diagnosis of AKI and the assessment of any risk factors allow the nephrologist to implement appropriate therapeutic strategies, such as pharmacological or extracorporeal support. Still, mortality in patients with AKI during COVID-19 remains high. COVID-19 AKI is a quickly evolving field of study.