再生障碍性贫血患者铁代谢异常及铁过载状况研究

Study on abnormal iron metabolism and iron overload in patients with aplastic anemia

目的研究再生障碍性贫血（AA）患者铁代谢异常，铁过载发病率及其高危影响因素，铁过载患者临床特征。方法对520例初诊AA患者的铁代谢指标进行横断面调查。结果520例初诊AA患者中66例（13％）存在铁过载，合并感染的86例AA患者铁过载发生率（22％）明显高于无感染者（11％）（P〈0．01），肝炎相关性AA（HAAA）患者铁过载发生率（32例中6例，19％）高于特发性AA患者（488例中60例，12％）。屏除合并感染的AA患者11％（405例中43例）存在铁过载，其中无输血史和有输血史的患者铁过载发生率分别为6％和18％（P〈0．01）。单因素分析结果显示血清铁蛋白（SF）、血清铁（SI）和转铁蛋白饱和度（TS）增高主要见于成年、男性的重型AA（SAA）患者，且随着输血量的增加而逐渐增高（P〈0．01）；不同年龄、性别、HAAA与特发性AA分组间可溶性转铁蛋白受体（sT依）水平差异无统计学意义，但合并感染的患者sTIR水平（0．50mg／L）明显低于无感染者（0．79mg／L，P〈0．01）；SAA患者sTIR水平（0．70mg／L）仅为非重型AA（NSAA）患者（1．36mg／L）的50％（P〈0．01）；输血及输血量的增加导致AA患者sTIR水平明显下降（P〈0．01）。多因素Logistic回归分析显示输血量超过8U（OR=10．5，P〈0．01）、成人（OR=3．48，P〈0．01）、男性（OR=3．32，P〈0．01）、合并感染（OR=2．09，P〈0．05）均为铁过载发生的独立危险因素。结论AA患者铁负荷增高是铁代谢异常的主要特点；AA患者是铁过载发生的高危人群，18％有输血史患者及6％无输血史患者均发生铁过载。

Objective To investigate the abnormalities of iron metabolism, the prevalence and risk factors of iron overload and clinical characteristics of patients with aplastic anemia （AA）. Methods A cross-sectional study was conducted on 520 newly diagnosed AA patients. Results Iron overload was observed in 66 （ 13 % ） of 520 AA patients, in which a higher prevalence of iron overload was seen not only in patients with infections （19/86, 22%） than those without infections （47/434, 11%, P〈0.01 ）, but also in patients with hepatitis associated AA （HAAA） （6/22, 19% ） than the idiopathic cases （60/488, 12%, P〉 0.05）. Excluded the patients with infections and/or HAAA, 43 of 405 （11% ） cases had iron overload, including 14 of 248 （6%） cases without history of blood transfusion and 29 of 157 patients （ 18%, P〈0.01 ） with transfusion. In univariate analysis, higher levels of serum ferritin （SF）, serum iron （SI） and transferrin saturation （TS） were mainly observed in adult male patients with severe AA （SAA） and significantly upward with increasing blood transfusion （P〈0.01）. No differences of soluble transferrin receptor （sTfR） were observed between adults and children, males and females, hepatitis and idiopathic AA. However, patients with infections had significantly lower level of sTfR （0.50 mg/L） than cases without infections （0.79 mg/L, P〈0.01 ）. The level of sTfR in SAA patients （0.70 mg/L） was only half of that in non-SAA （NSAA） （1.36 mg/L, P〈0.01）. Patients with increasing blood transfusion hadsignificantly downward levels of sTIR （P〈0.0I）. In multivariate analysis, more than 8 U blood transfusion （OR=10.52, P〈0.01 ）, adults （OR=3.48, P〈0.01 ）, males （OR=3.32, P〈0.01 ） and infections （OR=2.09, P〈 0.01 ） were independent risk factors. Conclusion AA patients had higher iron burden and were high-risk populations occurring iron overload. The iron overload occurred in 18% of patients with blood transfusion and in 6% of patients without transfusion.