Shafeghati Yousef, Vakili Ghazal, Entezari Ali
Genetics Research Center, University of Welfare Sciences and Rehabilitation, Tehran, Iran.
Arch Iran Med. 2006 Apr;9(2):165-9.
L-2-hydroxyglutaric aciduria is a rare and novel autosomal recessive inherited neurometabolic disorder. Since its first description by Duran in 1980, less than 100 cases have so far been reported. Occurring mostly in childhood, it is characterized by slowly progressive neurological dysfunction with cerebellar ataxia, pyramidal signs, intellectual decline, seizure, and extrapyramidal symptoms. MRI scanning is highly characteristic and screening for organic acid (L-2-hydroxyglutaric acid) in urine, serum, and cerebrospinal fluid is diagnostic. We investigated six Iranian children, aged 4, 14, 16, and 16 years, (the last one had two affected brothers and both of them died of similar illness at the ages of 20 and 22), by urinary organic acids assay and MRI scanning with suspicion of this rare disorder. Symptoms were suspicious for one of the leukoencephalopathies accompanied by macrocephaly. Affected cases were evaluated because of mild to moderate psychomotor retardation and regression. Head circumferences were above 2 standard deviations. Urine levels of L-2-hydroxyglutaric acid were strongly increased. MRI scanning of the brain showed hyperintense signal on T2W images of the subcortical white matter and basal ganglia in all of them. Because of its inheritance pattern (autosomal recessive) and the high rate of consanguineous marriages in Iran, the prevalence of this disorder might be high among the mentally-handicapped patients, especially those with macrocephaly. Therefore, this entity should be considered in the differential diagnosis of mentally-retarded patients with macrocephaly.
L-2-羟基戊二酸尿症是一种罕见的新型常染色体隐性遗传神经代谢疾病。自1980年杜兰首次描述该病以来,迄今报道的病例不到100例。该病多在儿童期发病,其特征为缓慢进展的神经功能障碍,伴有小脑共济失调、锥体束征、智力衰退、癫痫发作和锥体外系症状。MRI扫描具有高度特征性,对尿液、血清和脑脊液中的有机酸(L-2-羟基戊二酸)进行筛查可确诊。我们对6名伊朗儿童进行了研究,年龄分别为4岁、14岁、16岁和16岁(最后一名儿童有两个患病兄弟,他们分别在20岁和22岁时死于类似疾病),通过尿液有机酸检测和MRI扫描,怀疑他们患有这种罕见疾病。症状疑似为伴有巨头症的脑白质病之一。因轻度至中度精神运动发育迟缓及倒退对患病病例进行了评估。头围高于2个标准差。尿液中L-2-羟基戊二酸水平大幅升高。所有患儿脑部的MRI扫描在T2加权图像上均显示皮质下白质和基底神经节呈高信号。由于该病的遗传模式(常染色体隐性)以及伊朗近亲结婚率较高,这种疾病在智障患者中,尤其是患有巨头症的患者中患病率可能较高。因此,在对患有巨头症的智障患者进行鉴别诊断时应考虑到这种疾病。