Igor J. Koralnik

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Progressive multifocal leukoencephalopathy (PML) is a rare but often fatal brain disease caused by reactivation of the polyomavirus JC. Knowledge of the characteristics of PML has substantially expanded since the introduction of combination antiretroviral therapy during the HIV epidemic and the development of immune reconstitution inflammatory syndrome(More)
OBJECTIVE To establish criteria for the diagnosis of progressive multifocal leukoencephalopathy (PML). METHODS We reviewed available literature to identify various diagnostic criteria employed. Several search strategies employing the terms "progressive multifocal leukoencephalopathy" with or without "JC virus" were performed with PubMed, SCOPUS, and(More)
BACKGROUND We sought to determine the prevalence of JC virus (JCV) in bone marrow samples from human immunodeficiency virus (HIV)-positive and HIV-negative patients and to determine whether bone marrow is a site of latency and neurotropic transformation of JCV, the agent of progressive multifocal leukoencephalopathy (PML). METHODS We collected bone marrow(More)
Nothing is more disappointing for patients than when a promising new treatment hits a roadblock because of unexpected side effects. This is what happened when natalizumab (Tysabri) was associated with a few cases of progressive multifocal leukoencephalopathy (PML) in multiple sclerosis and Crohn's disease patients, caused by the reactivation of the(More)
Progressive multifocal leukoencephalopathy is caused by the JC polyomavirus (JCV) and is one of the most feared complications of HIV-1 infection. Unlike other opportunistic infections, this disease can present when CD4 counts are higher than those associated with AIDS and when patients are receiving combined antiretroviral therapy, either shortly after(More)
JC virus (JCV) is latent in the kidneys and lymphoid organs of healthy individuals, and its reactivation in the context of immunosuppression may lead to progressive multifocal leukoencephalopathy (PML). Whether JCV is present in the brains or other organs of healthy people and in immunosuppressed patients without PML has been a matter of debate. We detected(More)
To address the hypothesis that medulloblastoma or supratentorial primitive neuroectodermal tumor (sPNET) can arise through infection by polyomaviruses, we examined genomic DNA isolated from 15 primary medulloblastoma and 5 sPNET biopsy specimens and from 2 medulloblastoma cell lines for the presence of DNA sequences from the polyomaviruses simian virus 40(More)
OBJECTIVE To determine the clinical value of JC virus (JCV) detection in various anatomic compartments for the diagnosis of progressive multifocal leukoencephalopathy (PML). METHODS CSF, peripheral blood mononuclear cells (PBMC), plasma, and urine samples were evaluated from HIV-infected and uninfected individuals. JCV DNA was detected by PCR and was(More)
Three protein isoforms are encoded by the human T-cell leukemia/lymphotropic virus type I pX region open reading frames (ORF) I and II through alternative splicing. Both the singly and doubly spliced mRNAs from ORF I encode a single 12-kDa protein (p12I), whereas two distinct proteins of 13 kDa (p13II) and 30 kDa (p30II) are encoded from the ORF II(More)
BACKGROUND In the setting of severe immunosuppression, the polyomavirus JC (JCV) can cause a lytic infection of oligodendrocytes. This demyelinating disease of the CNS white matter (WM) is called progressive multifocal leukoencephalopathy (PML). JCV has a very narrow host-cell range and productive infection of neurons has never been demonstrated. Patient,(More)