[Study of abnormal iron metabolism parameters and iron overload in patients with myelodysplastic syndromes]

Objective: To investigate the abnormalities of iron metabolism parameters, the prevalence and risk factors of iron overload and clinical characteristics of patients with myelodysplastic syndromes(MDS). Methods: Retrospective investigation was used to observe abnormal iron metabolism parameters and clinical characteristics of newly diagnosed 94 MDS patients in our center from June 2015 to March 2016. Results: Of 94 patients, 71(75.53%)had a hemoglobin level of less than 100 g/L at diagnosis. Iron overload was observed in 52(55.32%)of 94 MDS patients, in which a higher prevalence of iron overload was observed in low risk groups(IPSS low/Int-1 risk groups)than higher risk groups(Int-2/high risk groups). Higher levels of serum iron(SI)[36.5(8.5-64.7)mmol/L vs 25.2(3.7-45.3)mmol/L, P<0.01], transferrin saturation(TSAT)[43.5(12.2-77.2)% vs 53.4(14.8-97.5)%, P <0.01]and serum ferritin(SF)were observed in iron overload group. No differences of labile cellular iron(LCI)and reactive oxygen species(ROS)were observed between two groups(P=0.88, P=0.06). As the results of clinical complication of iron overload, alanine aminotransferase(ALT)[25(3-158)U/L vs 16(5-80)U/L, P=0.03]and type B natriuretic peptide precursor(proBNP)[190(6-4281)ng/L vs 84(12-2 275)ng/L, P= 0.05]levels were increased in iron overload group. There was no significant difference in iron metabolism parameters between patients with refractory anemia(RARS)and non RARS patients(P>0.05). Both frequency and volume of RBC transfusion had a significant effect on all iron metabolism parameters(SI, TSAT and SF)(P <0.01)except LCI and ROS. Excluded the patients with history of blood transfusion and SF levels over 1 000 μg/L, higher levels of LCI were mainly observed in dysplastic erythropoiesis and increased bone marrow erythroblasts ratio groups(P<0.01, P<0.05). Conclusion: The main cause of iron overload in MDS is chronic transfusion therapy. Both frequency and intensity of transfusion regimen have a main effect on iron metabolism parameters. LCI levels are mainly increased in newly diagnosed patients with the abnormalities of iron metabolism and have a stronger association with dysplastic erythropoiesis and increased bone marrow erythroblasts ratio. As the toxic fraction of iron and its negative impact on MDS, iron overload monitoring and chelation treatment decision can also be supported by LCI.