Iron-Overload Evaluation by Noninvasive Methods in Patients with Nonalcoholic Fatty Liver Disease, Overweight, and Hyperferritinemia

Abstract

Introduction: Hyperferritinemia (HF) may reflect the inflammatory status of patients with NAFLD and obesity, but about 33% reflects a real hepatic iron overload. The dysmetabolic iron overload syndrome (DIOS) definition is HF, normal transferrin saturation, and mild hepatic iron overload in a patient with metabolic disorders. The gold standard for diagnosis of iron overload is the liver biopsy. As it is an invasive method, new methods are necessary. Among them, magnetic resonance imaging (MRI) is the most available one. Methods: This study evaluated patients with HF, overweight and NAFLD. All patients were submitted to liver biopsy. MRI relaxometry (Fat/Iron analysis - 3T machine), measurement of inflammatory markers (TNF α and IL-6), analysis of the expression of ferritin light and heavy chain subunits (FTL and FTH) and serum hepcidin were held. Data were correlated with liver biopsy. Results: 152 biopsy-proven NAFLD patients were screened but only 67 were included in this study. DIOS frequency was 37%. The cut off of ferritin levels were correlated with iron overload in liver biopsy was 284,3 ng/ml (sensibility of 74% and specificity of 84%). Hepcidin levels were higher in DIOS patients, correlating with hepatic siderosis. IL-6 and TNF α were similar among the groups. The expression of FTH and FTL were similar in role sample, although there was a tendency of FTL in iron overload group. In the other hand, FTL correlates with metabolic syndrome and abdominal circumference, while FTH correlates with in higher fat scores. The MRI was able to identify mild iron overload. The R2 * cut off level was 58,9 s -1. Conclusions: HF may reflect iron overload when above 284,3 ng/ml; MRI using relaxometry method is accurate to evaluate mild iron overload in DIOS patients; Hepcidin correlates with iron and serum ferritin in NAFLD patients; FTL correlates with metabolic syndrome and abdominal circumference while FTH correlates with in higher fat scores. Disclosure P.P.F. Branisso: None. C.P. Oliveira: None. H.M. Leão Filho: None. A. Santos: None. F.R. Lima: None. M. Mancini: None. F. Carrilho: None. M. Rocha: None. C. Cercato: None.