Comparison of serial serum ferritin measurements and liver iron concentration assessed by MRI in adult transfused patients with sickle cell disease

Abstract

Aims: Transfused patients with sickle cell disease (SCD) are at risk of iron overload and identifying such patients is important to prevent associated complications. Our aim was to assess the efficacy of serial serum ferritin (SF) measurements in identifying patients with hepatic iron overload as assessed by liver MRI and its usefulness in guiding decision making regarding chelation therapy.

Patients/methods: We retrospectively compared the results of 49 liver MRI scans (LS) with the median serum ferritin (MSF) values for 28 patients in our institution.

Results: We found a nonlinear increment of MSF with increasing liver iron concentration (LIC). 18.4% and 47.4% of abnormal LSs corresponded to MSF <1000 mcg/L and <2000 mcg/L, respectively. 30.4% of patients with LIC of 7 mg/g dry weight or higher had a MSF <2000 mcg/L. In 38.5% of patients receiving chelation, MSF offered little information regarding the efficacy of treatment and was sometimes misleading.

Conclusion: Serial serum ferritin measurements in adult transfused patients with sickle cell disease have a low sensitivity for identifying patients with iron overload and are of limited value in guiding decision making regarding initiation or monitoring of chelation therapy. The iron status of such high risk patients should be assessed by more definitive ways such as MRI.

Keywords: MRI; chelation; ferritin; iron; sickle cell.