Human Polyomavirus 6 DNA in cerebrospinal fluid of an HIV-positive patient with leukoencephalophaty

BACKGROUND: Leukoencephalopathies in HAART-treated, HIV-positive patients include progressive multifocal Leukoencephalopathy (PML), a result of lytic infection oligodendrocytes by JC polyomavirus (JCV), and another for characterized by the absence of JCV genome in cerebrospinal fluid (CSF) which we call here leukoencephalopathy of unknown origin (LEUO). OBJECTIVES: To test the potential viral etiology of LEUO. STUDY DESIGN: CSF was collected from 43 HIV-positive patients with MRI suggestive of leukoencephalopathies. DNA was isolated and real-time PCR assays for neurotropic viruses (Herpes Simplex Viruses 1/2, Varicella Zoster Virus, Epstein Barr Virus, Human Cytomegalovirus, Human Herpesvirus 6, JCVand HIV) were conducted. CSF from 14 non-reactive cases were subjected to random nucleic acid amplification, deep sequencing, and in silico search for viral sequences. RESULTS: JCV genome was detected in the CSF of 19 PML patients, HIV genome in the CSF of 5 PML patients including 2 JCV negative patients, and no viruses were detected in 22 LEUO patients. Human Polyomavirus 6 (HPyV6) DNA was detected by deep sequencing in one CSF sample. CONCLUSIONS: HPyV6 has not been previously reported in CSF or associated with any disease. HPyV6 DNAwas detected in CSF of a case of demy- elinating disease. Demonstrating a causative role will require further studies.