Diabetes Is the Main Factor Accounting for the High Ferritin Levels Detected in Chronic Hepatitis C Virus Infection: Response to Sebastiani et al.

After reading the comments by Sebastiani et al. (1) on our article (2) regarding the association between diabetes and ferritin in chronic hepatitis C virus (HCV) infection, we would like to make the following comments. In contrast to our results, the authors did not find any relationship between serum ferritin levels and glucose abnormalities in HCV-infected patients. However, it should be noted that the number of patients included in our study was much larger and, thereby, a statistical multivariate analysis considering sex (a major confounding factor) could be performed. In addition, because in our study a group of diabetic patients without HCV infection and a group of anti–HCV-negative nondiabetic control subjects were analyzed, we were able to conclude that the increase in ferritin levels detected in HCV patients was closely related to the presence of diabetes (2). Another concern of Sebastiani et al. is the high prevalence of diabetes in our population (21.7%). Although some influence could be attributed to the tertiary reference center setting of our study, it is more important to note that the HCV-infected patients included in our study were ∼10 years older that those reported by Sebastiani et al. In addition, our results agree with a previous study by our group that specifically addressed this issue (3). Concerning the higher serum ferritin levels detected in Sebastiani et al.’s population, it should be emphasized that most of the patients included in their study appear to have been in more advanced stages of chronic hepatitis than those in our study. Moreover, we are unaware whether they had ruled out hemochromatosis. Finally, we did not deny that there are other factors apart from diabetes accounting for the high serum ferritin levels detected in HCV-infected patients. In fact, the relationship between alanine aminotransferase and serum ferritin levels observed by Sebastiani et al. in univariate analysis was also observed by us in a multiple regression analysis (2). However, in light of our results, it would appear that diabetes is not only associated with higher serum ferritin levels but also is a significant factor accounting for the higher ferritin levels detected in HCV-infected patients.