一例铁剂难治性缺铁性贫血患者临床特征和基因确证

Identification and characterization of clinical features and gene mutation in a patient with iron-refractory iron deficiency anemia （IRIDA）

目的 通过报告1例铁剂难治性缺铁性贫血（IRIDA）病例资料,以提高对IRIDA的认识.方法 总结1例IRIDA患者及其家族成员血液学特征,采用ELISA法检测外周血铁调素（hepcidin）表达水平,采用PCR技术及DNA测序分析检测TMPRSS6基因突变情况,并通过Swiss-Model预测突变后对TMPRSS6蛋白三级结构的影响.结果 该例患者表现为典型小细胞低色素贫血,转铁蛋白饱和度明显低下,骨髓细胞内铁较细胞外铁减少更为明显,血浆hepcidin水平为213.77μg/L,与普通IDA患者的5.19（3.31～12.02） μg/L相比明显增高,TMPRSS6基因第7号外显子K253E纯合错义突变.结论 铁剂治疗反应不佳且缺乏明确铁缺乏病因的儿童和年轻成人缺铁性贫血,需考虑IRIDA,应进行血清hepcidin水平和TMPRSS6基因突变检测.

Objective To report the clinical data of a case of iron-refractory iron deficiency anemia （IRIDA）,so as to improve the understanding of IRIDA.Methods The IRIDA patient＇s hematological characteristics were summarized and analyzed.The hepcidin levels were tested by ELISA kit.The TMPRSS6 gene was amplified by PCR reaction and its mutation was analyzed by sequencing.The effect of TMPRSS6 gene mutation on TMPRSS6 protein tertiary structure was predicted by Swiss-Model.Results The patient was characterized by typical microcytic hypochromic anemia,low transferrin saturation,more reduction of intracellular iron than exocellular iron.The plasma hepcidin level was 213.77 μg/L which was significantly higher than that of IDA patients [5.19 （3.31-12.02） μg/L].The patient also carried a homozygous missense mutation of K253E in exon 7 of TMPRSS6.Conclusion In children and younger IDA patients with no reason for iron deficiency but unresponsiveness to routine iron treatment,the diagnosis of IRIDA needs to be considered.Serum hepcidin level and TMPRSS6 gene mutation should be detected.