Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada.
Medical Imaging Department, University of Toronto, Toronto, ON, Canada.
Pediatr Radiol. 2022 Feb;52(2):334-339. doi: 10.1007/s00247-021-05008-9. Epub 2021 Mar 12.
Neonatal hemochromatosis is a rare condition that causes neonatal liver failure, frequently resulting in fetal loss or neonatal death. It is thought that most cases of neonatal hemochromatosis are caused by gestational alloimmune liver disease (GALD), with neonatal hemochromatosis being a phenotype of GALD rather than a disease process. Extrahepatic siderosis in the pancreas, myocardium, thyroid and minor salivary gland is a characteristic feature of neonatal hemochromatosis. There is also sparing of the reticuloendothelial system with no iron deposition in the spleen. Hepatic and extrahepatic siderosis seen in neonatal hemochromatosis is from iron dysregulation secondary to liver damage rather than iron deposition causing the liver damage. The presence of extrahepatic siderosis in the pancreas and thyroid is diagnostic of neonatal hemochromatosis and can be detected noninvasively by multi-echo gradient recalled echo (GRE) T2*-weighted sequence of MRI within hours of birth. This helps to expedite the treatment in the form of intravenous immunoglobulin and exchange transfusion, which improves the survival in these babies. The finding of hepatic siderosis is nonspecific and does not help in the diagnosis of neonatal hemochromatosis because it is seen with other causes of advanced liver disease.
新生儿血色病是一种罕见的疾病，可导致新生儿肝功能衰竭，常导致胎儿丢失或新生儿死亡。大多数新生儿血色病病例被认为是由妊娠期同种免疫性肝病（GALD）引起的，新生儿血色病是 GALD 的一种表型，而不是一种疾病过程。胰腺、心肌、甲状腺和小唾液腺的肝外含铁血黄素沉着是新生儿血色病的一个特征。网状内皮系统也未受累，脾脏内无铁沉积。新生儿血色病中所见的肝外和肝内含铁血黄素沉着是由肝损伤引起的铁调节异常所致，而不是铁沉积导致肝损伤。胰腺和甲状腺中存在肝外含铁血黄素沉着是新生儿血色病的诊断依据，在出生后数小时内即可通过 MRI 的多回波梯度回波（GRE）T2*-加权序列无创检测到。这有助于通过静脉注射免疫球蛋白和交换输血进行治疗，从而提高这些婴儿的存活率。肝内含铁血黄素沉着的发现没有帮助，因为它也见于其他晚期肝病的原因，所以对新生儿血色病的诊断没有帮助。
