▪Objective: To observe the clinical characters and magnetic resonance imaging (MRI) T2* change in patients with aplastic anemia (AA) and low or int-1 risk of myelodysplastic syndromes(MDS) complicated with iron overload.Methods:This is a prospective study. Patients with AA and low and intermediate-1 risk factors of MDS complicated with iron overload were enrolled. Clinical parameters and T2* of liver, heart and pancreas were collected regularly.Results: Of all the 92 recruited patients (54 males and 38 females), the median age was 47.5 (15~18) year-old, median disease duration was 26 (3~407) months. There were 54 AA patients and 38 MDS patients. SF was related to liver T2* and pancreatic T2*(AA group r=-0.476,-0.509, respectively, P<0.05; MDS group r=-0.401, -0.565, respectively, P<0.05) in both groups, but not related to cardiac T2* in either group. SF level was correlated with transfusion amount in AA patients (r=0.403, P<0.05), but not in MDS patients (r=0.234, P>0.05. Of the 20 patients who received iron-chelation therapy, 3 (15%) had diarrheas, 2 (10%) decreased in hemoglobin, 2 (10%) decreased in platelet, 2 (10%) had increased creatinine, 1 (5%) had allergic dermatitis, but the symptoms relieved after drug withdrawal. 2 patients died of bone marrow failure during the follow-up period. 38 patients finished the half-year evaluation. Those (18 cases) who chelated adequately had significant decrease in SF (3354.9±3287.3 vs 2119.3±1742.0 ng/ml, P=0.044). Meanwhile an increase in hemoglobin level (83.5±30.0 vs 96.7±31.6 g/L, P=0.01) was noticed in those with decreased SF. 26 patients finished one year follow-up, those (15 cases) who chelated adequately had significant decrease in SF (3583.9±3543.8 vs 1693.9±1532.5 ng/ml, P=0.006), increase in cardiac T2* (25.0±13.4 vs 32.3±15.7 ms, P=0.015) and left ventricular ejection fraction (LVEF) (63.6±8.6 vs 67.1±5.2 %, P=0.028) , whereas no such changes were found in those did not chelate adequately. No change was found either in chelated or non-chelated groups in hemoglobin, WBC count, platelet count, SGPT, TBil, creatinine level, liver or pancreas T2* value. For those with decreased SF, even without chelation, increase in hemoglobin level (91.1 ±29.9 vs 108.4±31.4 g/L, P=0.046),cardiac T2* (25.5±13.7 vs 33.1±15.9 ms, P=0.014)) and LVEF level (63.6±8.6 vs 67.2±5.4 %, P=0.027) were also documented.Conclusion: SF was related to liver T2* and pancreatic T2* in both AA and MDS groups. SF was relevant to transfusion amount in patients with AA but not MDS. Adequate iron chelation can decrease the SF level, and might bring improvement in cardiac T2* and LVEF level. Decrease of SF even without chelation might also benefit patients. DisclosuresNo relevant conflicts of interest to declare.