Axonal chronic injury in treatment-naive HIV plus adults with asymptomatic neurocognitive impairment and its relationship with clinical variables and cognitive status

作者：Li, Rui-li; Sun, Jun; Tang, Zhen-chao; Zhang, Jing-ji^*; Li, Hong-jun^*

来源：BMC Neurology, 2018, 18(1): 66.

DOI：10.1186/s12883-018-1069-5

• HIV
• Asymptomatic neurocognitive impairment
• White matter
• Diffusion tensor imaging

Background: HIV is a neurotropic virus, and it can bring about neurodegeneration and may even result in cognitive impairments. The precise mechanism of HIV-associated white matter (WM) injury is unknown. The effects of multiple clinical contributors on WM impairments and the relationship between the WM alterations and cognitive performance merit further investigation.
Methods: Diffusion tensor imaging (DTI) was performed in 20 antiretroviral-naive HIV-positive asymptomatic neurocognitive impairment (ANI) adults and 20 healthy volunteers. Whole-brain analysis of DTI metrics between groups was conducted by employing tract-based spatial statistics (TBSS), including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). DTI parameters were correlated with clinical variables (age, CD4(+) cell count, CD4(+)/CD8(+) ratio, plasma viral load and duration of HIV infection) and multiple cognitive tests by using multilinear regression analyses.
Results: DTI quantified diffusion alterations in the corpus callosum and corona radiata (MD increased significantly, P < 0.05) and chronic axonal injury in the corpus callosum, corona radiata, internal capsule, external capsule, posterior thalamic radiation, sagittal stratum, and superior longitudinal fasciculus (AD increased significantly, P < 0.05). The impairments in the corona radiata had significant correlations with the current CD4(+)/CD8(+) ratios. Increased MD or AD values in multiple white matter structures showed significant associations with many cognitive domain tests.
Conclusions: WM impairments are present in neurologically asymptomatic HIV+ adults, periventricular WM (corpus callosum and corona radiata) are preferential occult injuries, which is associated with axonal chronic damage rather than demyelination. Axonopathy may exist before myelin injury. DTI-TBSS is helpful to explore the WM microstructure abnormalities and provide a new perspective for the investigation of the pathomechanism of HIV-associated WM injury.

• 出版日期2018-5-10
• 单位首都医科大学; 山东大学