Serum ferritin in neonatal cholestasis: A specific and active molecule or a non-specific bystander marker?

Background: Serum ferritin (SF) and consequently hepatic iron have long been considered important in liver fibrosis progression. They have been studied in different liver diseases with no previous reports in neonatal cholestasis (NC). This study aimed to measure SF in different etiologies of NC and investigate its relation to hepatic iron and fibrosis.

Methods: SF was measured in 75 infants, including 50 with NC and 25 with sepsis. SF was compared between these two groups. Biochemical parameters, hepatic iron grades, and liver fibrosis and other histopathological characteristics and correlated with SF were assessed in NC group. Finally, a comparison between intrahepatic cholestasis and obstructive etiology was performed.

Results: SF was elevated in NC (1598 ± 2405 ng/mL) with no significant difference from those with sepsis (P = 0.445). NC and sepsis constituted augmenting factors leading to more elevation of SF (2589 ± 3511 ng/mL). SF was significantly correlated with hepatic iron grades (r = 0.536, P < 0.0001) and a cut-off value of 803.5 ng/mL can predict higher grades (≥ grade 3) of iron deposition with sensitivity of 100%, specificity of 70% and accuracy of 85%. Moreover, SF was significantly higher (P < 0.0001) in those with intrahepatic cholestasis (2602 ± 3154 ng/mL) and their prevalent pathological findings of giant cell transformation (P = 0.009) and hepatocyte swelling (P = 0.023) than those with obstructive etiology (672 ± 566 ng/mL) and their prevalent pathological findings of ductular proliferation (P = 0.003) and bile plugs (P = 0.002). SF was unrelated to the grade of liver fibrosis (P = 0.058).

Conclusions: SF is non-specifically elevated in NC, with positive correlation to hepatic iron grades. SF ≥ 803.5 ng/mL can predict higher grades (≥ grade 3) of hepatic iron. However, an active role of increased SF and hepatic iron in disease progression remains questionable.