Utility of multi-echo MRI for differentiating neonatal hemochromatosis from other causes of neonatal liver failure.

objectiveTo assess whether multi-echo T2* MRI can differentiate neonatal hemochromatosis (NH) from other causes of neonatal liver failure (NLF) by evaluating siderosis in the liver and extrahepatic organs. MATERIALS AND

methodsThis retrospective study evaluated 26 infants ≤ 20 weeks of age, who underwent MRI with Gradient-Recalled (GRE) multi-echo T2* sequence for liver failure. Two radiologists noted the degree of siderosis in the liver, pancreas, thyroid, spleen and renal cortex using a semiquantitative scale. Kendall's tau was used to assess the correlation between siderosis grades and final diagnosis. Consensus review by hepatologist, neonatologist, and pathologist using integrated clinical, biochemical, imaging and histopathologic data served as the reference standard for the final diagnosis.

resultsOf 26 patients, 7 had NH and 19 had other causes of NLF. Interobserver agreement was highest for liver (κ = 0.97), followed by kidney (κ = 0.87), spleen (κ = 0.84), thyroid (κ = 0.80), and pancreas (κ = 0.73). Significant positive correlations between siderosis grades and NH diagnosis were found for thyroid (Kendall's tau = 0.70, p < 0.01), pancreas (Kendall's tau = 0.67, p < 0.01), and liver (Kendall's tau = 0.42, p = 0.03), while spleen showed a significant negative correlation (Kendall's tau = -0.51, p < 0.01). MRI demonstrated 100% sensitivity, 89.5% specificity, 77.8% positive predictive value, 100% negative predictive value, and 92.3% overall accuracy for NH diagnosis. There were significant differences among groups in R2* values for the pancreas, thyroid and spleen, with no differences in the liver.

conclusionMulti-echo T2* MRI reliably distinguishes NH from other causes of NLF by revealing significant siderosis in the thyroid and pancreas, with relative sparing of the spleen. KEY POINTS: Question Neonatal hemochromatosis (NH) is a rare but often fatal condition causing neonatal liver failure (NLF), and differentiating it from other causes of NLF is challenging. Finding Pancreatic and thyroid iron deposition, as seen on MRI, strongly correlated with NH, and splenic iron deposition correlated inversely with NH. Clinical relevance Multi-echo T2* MRI is a highly accurate, non-invasive technique for early differentiation of neonatal hemochromatosis from other liver failure causes, potentially enabling earlier diagnosis of NH and guiding crucial management decisions in affected neonates.