Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa.
Am J Med. 2013 Nov;126(11):1010-5. doi: 10.1016/j.amjmed.2013.07.013. Epub 2013 Sep 18.
Hereditary hemochromatosis is a disorder that can cause iron overload and organ damage. Hereditary hemochromatosis is characterized by mutations in the HFE gene. HFE C282Y homozygotes and compound heterozygotes (C282Y/H63D) are at risk of developing manifestations of hemochromatosis. Abnormal iron study results also occur in many liver and hematologic diseases. The aim of this study was to evaluate the accuracy of diagnosis of hereditary hemochromatosis.
Pertinent clinical and laboratory data, including HFE genotype, were tabulated from the electronic medical records of patients with the International Classification of Diseases 9th Revision code 275, "disorders of iron metabolism," who were seen at a tertiary referral center between January 2002 and May 2012.
HFE genotyping was obtained in only 373 of 601 patients (62%); 200 were C282Y homozygotes or compound heterozygotes. Of the 173 patients with nonhereditary hemochromatosis genotypes, 53% were misdiagnosed with hereditary hemochromatosis and 38% underwent phlebotomy. In two thirds of these cases, the misdiagnosis was made by a nonspecialist. In the remaining 228 patients who were not genotyped, 80 were diagnosed with hereditary hemochromatosis and 64 were phlebotomized. Of patients misdiagnosed with hemochromatosis, 68% had known liver disease and 5% had a hematologic cause of abnormal iron study results.
Abnormal iron study results in patients with nonhereditary hemochromatosis genotypes commonly lead to a misdiagnosis of hereditary hemochromatosis and inappropriate treatment with phlebotomy. This error often is seen in the setting of elevated iron study results secondary to chronic liver diseases. Furthermore, hereditary hemochromatosis is commonly diagnosed and treated without HFE genotyping. We suggest that phlebotomy centers require a documented HFE genotype before initiating phlebotomy.
遗传性血色素沉着症是一种可导致铁过载和器官损伤的疾病。遗传性血色素沉着症的特征是 HFE 基因突变。HFE C282Y 纯合子和复合杂合子(C282Y/H63D)有发生血色素沉着症表现的风险。异常的铁研究结果也发生在许多肝脏和血液疾病中。本研究旨在评估遗传性血色素沉着症诊断的准确性。
从 2002 年 1 月至 2012 年 5 月在三级转诊中心就诊的国际疾病分类第 9 版代码 275“铁代谢紊乱”患者的电子病历中列出了相关的临床和实验室数据,包括 HFE 基因型。
仅对 601 例患者中的 373 例(62%)进行了 HFE 基因分型;200 例为 C282Y 纯合子或复合杂合子。在 173 例非遗传性血色素沉着症基因型患者中,53%被误诊为遗传性血色素沉着症,38%接受了放血治疗。在这些病例中有三分之二的误诊是由非专家做出的。在其余未进行基因分型的 228 例患者中,80 例被诊断为遗传性血色素沉着症,64 例接受了放血治疗。在被误诊为血色素沉着症的患者中,68%有已知的肝脏疾病,5%有异常铁研究结果的血液学原因。
患有非遗传性血色素沉着症基因型的患者异常的铁研究结果常导致遗传性血色素沉着症的误诊和不适当的放血治疗。这种错误通常发生在因慢性肝脏疾病导致铁研究结果升高的情况下。此外,遗传性血色素沉着症常未经 HFE 基因分型诊断和治疗。我们建议放血治疗中心在开始放血前需要有记录的 HFE 基因型。