Progressive multifocal leukoencephalopathy and JC virus genotypes in west African patients with acquired immunodeficiency syndrome - A pathologic andDNA sequence analysis of 4 cases

Objective-Progressive multifocal leukoencephalopathy is caused by polyomavi rus JC in immunosuppressed patients. IC virus genotypes are identified by s equence analysis of the viral genome. Despite the prevalence of acquired im munodeficiency syndrome in sub-Saharan Africa, few cases of progressive mul tifocal leukoencephalopathy have been reported from this region. Here we de scribe 4 African cases and provide an analysis of viral genotypes. Methods.-Immunohistochemical staining by labeled streptavidin-biotin for ca psid protein antigen was performed on all cases. Polymerase chain reaction amplification of viral genomic DNA was followed by direct cycle sequencing. Results.-JC virus type 3 was identified in 2 cases, and type 6 was isolated in 1 case. The viral regulatory region from 1 case showed an uncommon rear rangement pattern. Conclusions.-Progressive multifocal leukoencephalopathy in West African pat ients with acquired immunodeficiency syndrome is caused by African genotype s of JC virus (types 3 and 6). The prevalence of disease in this autopsy se ries from sub-Saharan Africa (1.5%) was less than has been reported from Eu rope and the United States (4% to 10%) and may be partly due to biological differences in JC virus genotypes. Further studies will be needed to confir m this observation.