Tracey I, Carr C A, Guimaraes A R, Worth J L, Navia B A, González R G
Massachusetts General Hospital, NMR Center, Charlestown, MA 02129, USA.
Neurology. 1996 Mar;46(3):783-8. doi: 10.1212/wnl.46.3.783.
The CNS is frequently involved in human immunodeficiency virus (HIV) infection. In recent studies using proton magnetic resonance spectroscopy, investigators found a significant reduction in N-acetyl aspartate, a metabolic marker of neurons, in late stages of dementia. To further understand the relationship between proton magnetic resonance spectroscopy changes and clinical disease and dementia, we compared 20 HIV-infected patients presenting at varying stages of acquired immunodeficiency syndrome (AIDS) dementia complex and infection to 10 age-matched controls. We found a significant reduction in N-acetyl aspartate/creatine only in patients who had advanced dementia and CD4 counts less that 200/microliter. By contrast, a significant elevation in compounds containing choline was present in patients in the early stages of HIV infection of who had CD4 counts greater than 200/microliter, in patients with normal MRI scans, and in all AIDS dementia complex groups, including subjects with no or minimal cognitive impairment. An elevated choline level also occurred in later stages of HIV infection (CD4 < 200/microliter). Our results suggest that an increase in choline occurs before N-acetyl aspartate decrements, MRI abnormalities, and the onset of dementia, and may therefore provide a useful marker for early detection of brain injury associated with HIV infection.
中枢神经系统常累及人类免疫缺陷病毒(HIV)感染。在最近使用质子磁共振波谱的研究中,研究人员发现,在痴呆晚期,神经元的代谢标志物N-乙酰天门冬氨酸显著减少。为了进一步了解质子磁共振波谱变化与临床疾病及痴呆之间的关系,我们将20例处于获得性免疫缺陷综合征(AIDS)痴呆综合征和感染不同阶段的HIV感染患者与10例年龄匹配的对照进行了比较。我们发现,只有那些患有晚期痴呆且CD4细胞计数低于200/微升的患者,其N-乙酰天门冬氨酸/肌酸显著降低。相比之下,在CD4细胞计数大于200/微升的HIV感染早期患者、MRI扫描正常的患者以及所有AIDS痴呆综合征组(包括无认知障碍或轻度认知障碍的受试者)中,含胆碱的化合物显著升高。在HIV感染后期(CD4<200/微升)胆碱水平也会升高。我们的结果表明,胆碱升高发生在N-乙酰天门冬氨酸减少、MRI异常及痴呆发作之前,因此可能为早期检测与HIV感染相关的脑损伤提供一个有用的标志物。