Assessment of neuronal density in the putamen in human immunodeficiency virus (HIV) infection. Application of stereology and spatial analysis of quadrats.

Human immunodeficiency virus causes neuronal loss in various brain regions, but it has not been reported in the putamen. However, decrease in the volume of the putamen has been observed by magnetic resonance imaging. In order to clarify this issue two complementary methods; the stereological probe, the disector, and spatial analysis of quadrats, were applied in nondemented individuals who had died of acquired immune deficiency syndrome. A 21% decrease in neuronal density was observed in the human immunodeficiency virus group, especially those cases with human immunodeficiency virus encephalitis; however the statistical significance of this finding was borderline.