Frazier D M, Summer G K, Chamberlin H R
Am J Dis Child. 1978 Aug;132(8):777-81. doi: 10.1001/archpedi.1978.02120330049013.
Two preschool-age siblings with similar histories of encephalopathy were examined for developmental retardation and found to have elevated levels of urinary and blood glycine. Their inability to convert glycine into serine in the absence of elevated blood and urinary ketone levels was suggestive of a defect in the glycine-cleavage enzyme system (or serine hydroxymethyl transferase). These patients differ significantly from the majority of reported cases of nonketotic hyperglycinemia in that they did not manifest life-threatening neonatal illness, severe mental retardation, or neurological deficits. However, during an oral glycine load, alterations in the electroencephalographic pattern occurred that suggested a relationship between elevated blood glycine levels and pathological involvement of the central nervous system. The ratio of CSF-blood glycine was found to be in the range expected for nonketotic hyperglycinemia.
对两名有相似脑病病史的学龄前同胞进行发育迟缓检查，发现其尿液和血液中的甘氨酸水平升高。在血液和尿液酮水平未升高的情况下，他们无法将甘氨酸转化为丝氨酸，这提示甘氨酸裂解酶系统（或丝氨酸羟甲基转移酶）存在缺陷。这些患者与大多数已报道的非酮症高甘氨酸血症病例有显著不同，因为他们没有表现出危及生命的新生儿疾病、严重智力发育迟缓或神经功能缺损。然而，在口服甘氨酸负荷试验期间，脑电图模式出现改变，这表明血液中甘氨酸水平升高与中枢神经系统的病理受累之间存在关联。脑脊液与血液中甘氨酸的比值处于非酮症高甘氨酸血症预期的范围内。
