Hepcidin Removal during Continuous Renal Replacement Therapy

Area of Science:

• Nephrology
• Critical Care Medicine
• Immunology

Background:

• Continuous renal replacement therapy (CRRT) is essential for managing acute kidney injury (AKI) and end-stage kidney disease (ESKD).
• CRRT's broad solute removal may inadvertently deplete beneficial substances like hepcidin, an antimicrobial peptide crucial for iron homeostasis and pathogen defense.

Purpose of the Study:

• To investigate the effect of CRRT initiation on serum hepcidin levels in patients with AKI or ESKD.
• To determine if CRRT significantly alters hepcidin concentrations during treatment.

Main Methods:

• A prospective, observational study involving 13 patients requiring CRRT (11 with AKI, 2 with ESKD).
• Plasma and effluent samples were collected over 3 days post-CRRT initiation.
• Hepcidin concentrations were measured and compared to healthy controls; the hepcidin sieving coefficient was calculated.

Main Results:

• Patients initiating CRRT had significantly higher baseline hepcidin levels compared to healthy controls (158 ± 60 vs. 17 ± 3 ng/mL).
• Hepcidin levels decreased significantly by day 1 (102 ± 24 ng/mL) and day 2 (56 ± 14 ng/mL) of CRRT, stabilizing by day 3 (51 ± 11 ng/mL).
• The median hepcidin sieving coefficient was consistently high (0.82-0.83), indicating efficient removal by CRRT.

Conclusions:

• CRRT initiation leads to a rapid and significant reduction in plasma hepcidin levels within the first two days of treatment.
• This reduction occurs irrespective of the reason for CRRT or the presence of underlying ESKD.
• Given the association of low hepcidin with increased mortality, further clinical studies are needed to explore the impact of CRRT-induced hepcidin removal on patient outcomes.