Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Türkiye.
Faculty of Medicine, Hacettepe University, Ankara, Türkiye.
Turk J Pediatr. 2024 Nov 16;66(5):658-665. doi: 10.24953/turkjpediatr.2024.4522.
Iron refractory iron deficiency anemia (IRIDA) is a rare autosomal recessive type of anemia characterized by unresponsiveness to oral iron therapy and partial response to parenteral iron therapy. In this article, we report the clinical presentation of four patients with IRIDA admitted to our clinic, including their laboratory values at admission and after oral and parenteral iron treatment, and the analysis of their mutation(s) in TMPRSS6 gene.
Four patients from different families, aged between 3 and 14 years, two girls and two boys, two of whom were from consanguineous marriages, who were diagnosed with iron deficiency anemia in primary health care institutions and referred to our clinic because of inadequate response to oral iron treatment were included. Patients were evaluated for the differential diagnosis of microcytic, hypochromic anemia and investigated for the etiology of IDA. Homozygous or compound heterozygous mutations causing defective matriptase-2 protein expression were detected in the TMPRSS6 gene; these mutations included four frameshift mutations-two of which were the same in two cases and causing premature terminal stop codons-and a nonsense mutation, all of which were previously demonstrated in the literature. The response to parental iron therapy ranged from complete non-response to mild to good response in hemoglobin levels, but none of the patients showed improvement in iron parameters.
Increased awareness of IRIDA and keeping it in mind in the differential diagnosis in the presence of hypochromic microcytic anemia that does not respond to iron treatment will be crucial in improving the diagnosis and treatment of the disease and ultimately enhancing the quality of care for affected individuals.
铁难治性缺铁性贫血(IRIDA)是一种罕见的常染色体隐性贫血,其特征为对口服铁治疗无反应,对肠外铁治疗部分反应。本文报道了我们诊所收治的 4 例 IRIDA 患者的临床表现,包括他们入院时和口服及肠外铁治疗后的实验室值,以及对其 TMPRSS6 基因突变的分析。
来自不同家庭的 4 名患者,年龄 3 至 14 岁,2 女 2 男,其中 2 例来自近亲婚姻,他们在初级保健机构被诊断为缺铁性贫血,并因口服铁治疗反应不足而转至我们诊所。对患者进行了小细胞低色素性贫血的鉴别诊断评估,并对 IDA 的病因进行了调查。在 TMPRSS6 基因中检测到导致 matriptase-2 蛋白表达缺陷的纯合子或复合杂合突变;这些突变包括 4 种移码突变——其中 2 种在 2 例中相同,导致提前终止密码子——和 1 种无义突变,所有这些突变在文献中均有报道。对肠外铁治疗的反应范围从血红蛋白水平的完全无反应到轻度至良好反应,但没有患者的铁参数得到改善。
提高对 IRIDA 的认识,并在存在对铁治疗无反应的低色素性小细胞性贫血的鉴别诊断中牢记这一点,对于改善疾病的诊断和治疗,并最终提高受影响个体的护理质量至关重要。