Era of metabolic dysfunction-associated steatotic liver disease and impact on the liver donor pool

Table 1 Outcomes in liver graft according to the degree of steatosis

Steatosis grade	Steatosis range (%)	1-year survival (%)	Associated risks	Risk of PNF	Additional notes	Ref.
Grade 1 (low risk)	< 30	> 90	Low risk of DGF and PNF	Very low (almost nonexistent)	Grafts with low risk, acceptable for a wide variety of recipients. Very low rates of PNF and DGF	[21]
Grade 2 (moderate risk)	30-60	89-90	Moderate risk of DGF and PNF	Moderate	Requires careful recipient evaluation and optimized perioperative management. Use of NMP improves outcomes	[5,22]
Grade 3 (high risk)	> 60	< 80	High risk of PNF, early allograft dysfunction, and increased mortality	High	High rate of ischemia-reperfusion injury and graft dysfunction. Use of NMP may improve outcomes when the right recipient is selected	[5,17,22]

PNF: Primary nonfunction; DGF: Delayed graft dysfunction; NMP: Normothermic machine perfusion.

Table 2 Risk factors associated with liver steatosis in grafts from living and deceased brain-dead donors

Factor	Living donor	Deceased donor	Ref.
Age (years)	> 40	> 50	[96-98]
BMI (kg/m²)	> 25	> 30	[96,98]
Sex	Male	Male	[96,98]
Metabolic syndrome	Diabetes, hypertension, dyslipidemia	Common, often underdiagnosed	[45,97]
MASLD	Personal or family history	High prevalence, especially in obese individuals	[45]
Alcohol consumption (g/day)	> 20	> 40 chronically (> 5 years) or recent acute use	[45]
Preoperative assessment	Imaging (MRI, US, CAP) + selective biopsy	Limited, visual or back table biopsy if available	[34,36,99,100]
Perimortem conditions	N/A	Hypoxia, sepsis, prolonged support (> 72 hours MV, > 48 hours vasopressors, > 5 days in the ICU)	[101]
Cold ischemia	30-60 minutes	> 10 hours	[97]
Expected outcome	Minimal damage, good recovery	Higher risk of dysfunction due to ischemia and steatosis	[102]
Graft preservation	Excellent (scheduled)	Variable (depending on logistics and center)	[102]

BMI: Body mass index; MASLD: Metabolic dysfunction-associated steatotic liver disease; MRI: Magnetic resonance imaging; US: Ultrasound; CAP: Controlled attenuation parameter; N/A: Not applicable; MV: Mechanical ventilation; ICU: Intensive care unit.