Diffusion Tensor Imaging and Neuropsychological Outcomes in HIV/HCV Co-infection

项目摘要/摘要 据估计，几乎三分之一的艾滋病毒阳性患者同时感染了丙型肝炎病毒。对混合感染人群的认知功能的研究发现，与单独感染艾滋病毒或丙型肝炎病毒的人群相比，在许多认知领域的神经心理学检查中表现更差(Cherner等人，2008年；Clifford等人，2005年；Hilsabeck等人，2005年；Letendre等人，2002年；Martin等人，2004年；Parsons等人，2006年；Ryan等人，2004年；von Giesen等人，2004年)。此外，据报道，合并感染者更容易患上艾滋病痴呆症(Ryan等人，2004年)。尽管有一致的发现表明，合并感染的认知功能下降，但到目前为止，还没有发表过使用神经成像技术来研究合并感染对中枢神经系统的影响的报告。有几项已发表的研究使用核磁共振技术来确定丙型肝炎病毒单一感染对大脑的影响；在丙型肝炎病毒中实施磁共振波谱(MRS)的研究发现了与脑白质完整性破坏相关的标志物(Weissenborn et。其他)与MRS在艾滋病毒上的发现类似。在HIV中使用扩散张量成像(DTI)的研究数量有限，研究结果表明白质受损，即使白质看起来正常(Stebbins等人，2007年)。在混合感染中发现的神经心理缺陷和使用MRS在丙型肝炎病毒中发现的类似发现，尽管有限，但促使专门设计的额外研究来检查联合感染对大脑的影响。需要使用对白质变化敏感的新的成像技术来确定合并感染时发生的损伤程度，并可能导致更早的诊断和改善神经症状的治疗。我们认为，DTI是检查中枢神经系统合并感染的最佳工具，因为它对检测白质结构完整性的变化具有特异性。此外，由于并不是所有的研究都确定了丙型肝炎病毒合并感染状态对脑功能的显著影响，因此需要一种多学科的方法，包括神经心理评估、神经成像指标和实验室数据。这项研究将在DTI测量和神经心理测试上比较HIV阳性个体和HIV/丙型肝炎病毒混合感染者的样本，以确定大脑中联合感染的特征。这项拟议的研究将首次将这些区域具体整合到共同感染人群中。

Project Summary/Abstract It is estimated that almost a third of HIV-positive patients are co-infected with hepatitis C virus. Studies examining cognitive function in co-infected groups have found worse performance on neuropsychological examinations in a number of cognitive domains compared to groups with HIV or HCV alone (Cherner et al., 2008; Clifford et al., 2005; Hilsabeck,et al., 2005; Letendre et al., 2002; Martin et al., 2004; Parsons et al., 2006; Ryan et al., 2004; von Giesen et al., 2004). Additionally, it has been reported that co-infected persons are significantly more likely to develop AIDS dementia complex (Ryan et al., 2004). Despite the consistent findings of decreased cognitive functioning in co-infection, to date, there are no published reports using neuroimaging designed to study the impact of co-infection in the CNS. There are a few published studies using MRI techniques to determine the impact of HCV mono-infection on the brain; studies implementing Magnetic Resonance Spectroscopy (MRS) in HCV have found markers associated with the breakdown of white matter integrity (Weissenborn et. al list others) similar to MRS findings in HIV. There are a limited number of studies using diffusion tensor imaging (DTI) in HIV, with findings indicating white matter compromise, even in white matter that appears normal (Stebbins et al., 2007). The neuropsychological deficits found in co-infection and the similar findings in HCV using MRS, though limited, prompt additional research specifically designed to examine the effects co-infection on the brain. Novel imaging techniques that are sensitive to white matter changes need to be employed to determine the extent of injury that occurs in co-infection, and perhaps lead to earlier diagnosis and improved treatment of neurological symptoms. We believe DTI is the best tool to examine co-infection in the CNS, due to its specific sensitivity to detect changes in white matter structural integrity. Further, as not all studies have identified a significant effect of HCV co-infection status on brain function, a multidisciplinary approach is needed inclusive of neuropsychological assessment, neuroimaging indices and laboratory data. This study will compare a sample of HIV-positive individuals to HIV/HCV co-infected individuals on DTI measures, as well as neuropsychological tests, to determine the signatures of co-infection in the brain. The proposed study will be the first to integrate these areas specifically in a co-infected population.