Evaluating the Volumetric Liver Fat Fraction in Patients Referred for Investigation of Hyperferritinemia

Introduction Elevated serum ferritin (hyperferritinemia, HF) can result from increased iron load, increased inflammation or from liver damage. In the most common forms of hereditary hemochromatosis (HH), elevated ferritin is usually seen with elevated transferrin saturations, [1,2]. In patients with HF but without raised liver iron concentration (LIC, mg/g dry wt [dw]), increased liver fat (hepatic steatosis, HS), either in isolation or as part of a metabolic syndrome, needs to be considered. HS is important to identify as it may progress to chronic liver damage and is potentially reversible with lifestyle interventions. Hepatic fat can now be quantified with magnetic resonance imaging (Hepafat-Scan®)[3]. Here, we evaluate the usefulness of this method in the diagnosis and subsequent management of patients referred with HF. Methods A total of 132 patients (median age 48 years, range 21-86 ; female: male ratio 1:2.5) referred for investigation of HF and who underwent estimation of liver iron concentration (LIC) by R2-MRI (FerriScan®) over a four-year period (January 2015 - December 2018) are included in this analysis. Data on patient demographics, presenting serum ferritin (SF) and transferrin saturation were obtained. Genetic testing for C282Y and H63D was also performed. Genetic testing for rarer forms of haemochromatosis was confined to patients with unexplained raised LIC. Patients with iron overload secondary to chronic iron ingestion or blood transfusion were excluded from this analysis. Results Patients were subdivided by genetic diagnosis: C282Y homozygote (26, 19.7%), C282Y/H63D (18, 13.6%), H63D homozygote (10, 7.6%), C282Y heterozygote (8, 6.1%), H63D heterozygote (18, 13.6%), autosomal dominant ferroportin disease (4, 3%) and negative HFE gene testing (48, 36.4%). There was no statistical difference between mean presenting SF (p= 0.307) between the different groups. C282Y homozygotes, and those with autosomal ferroportin disease had a significantly higher LIC than others (p