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Results for “Leukoencephalopathy, Progressive Multifocal”

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PubMed2000

Quantitation of polyomavirus DNA by a competitive nested polymerase chain reaction.

A new method to quantitate small amounts of DNA in clinical specimens is described. The method, a nested competitive polymerase chain reaction (ncPCR), is able to quantitate between 10 and 10(6) copies per tube of polyomavirus DNA and shows good reproducibility when clinical samples are analysed. Throughout the whole procedure, an internal standard (IS) competes for the primers with the target DNA. The internal standard, a heterologous sequence containing the four primer recognition sites, was constructed using a modification of the 'MIMIC' approach that is useful for obtaining competitor sequences for any viral, bacterial or eukaryotic target. The ncPCR method for polyomavirus was applied to cerebrospinal fluids (CSF) from AIDS patients with progressive multifocal leukoencephalopathy (PML) and urine specimens from bone marrow transplant patients affected by haemorrhagic cystitis. The results obtained suggest that the ncPCR method is a sensitive and useful method for quantitating genomic load in clinical samples.

Acquired Immunodeficiency Syndrome↗

PubMed1965

PARTICLES RESEMBLING PAPOVA VIRUSES IN HUMAN CEREBRAL DEMYELINATING DISEASE.

Degenerated brain tissue obtained from a deceased patient who had progressive multifocal leukoencephalopathy had been fixed in formalin prior to processing for electron microscopy. In ultrathin sections virus-like particles resembling papova virions were frequently observed in glial nuclei. Correlation with light-microscopy findings suggests that demyelination resulted from the cytocidal effect of the virus on oligodendroglia.

Brain Diseases↗

PubMed2001

[Brain SPECT with 201-thallium in AIDS patients].

UNLABELLED: Brain lymphoma is a late complication in AIDS. Lymphoma incidence is increasing in AIDS patients due to the introduction of HAART and prolongation of these patients' life expectancy. This work aims to evaluate the usefulness of brain SPECT with 201Tl in patients with AIDS who present focal brain lesions in computed tomography (CT). METHODS: Seventeen patients with neurologic symptoms and focal neurologic lesions in the CNS (central nervous system) were studied. The images were interpreted as positive when the intensity of the focal deposit of the tracer was greater than that of the adjacent tissue. The SPECT results were compared with serologic data, clinical evolution and/or radiologic follow-up and cerebral biopsy. RESULTS: SPECT images showed focal uptake of radiotracer in 3 patients. All three died shortly after the SPECT was performed. All of them had negative serology for toxoplasmosis. Four patients were diagnosed of progressive multifocal leukoencephalopathy and the ten remaining cases had a good clinical and/or radiologic response. CONCLUSIONS: Brain SPECT with 201Tl is a very useful non-invasive technique for the differential diagnosis of cerebral focal lesions in AIDS patients.

Adult↗

PubMedDate not supplied

Case report. Simultaneous fungal and viral infection of the central nervous system.

A patient with lymphoma developed central nervous system dysfunction and the diagnosis of cryptococcal meningitis was made. Because of discordant clinical and laboratory responses to appropriate treatment, further investigations were performed and the additional diagnosis of progressive multifocal leukoencephalopathy (PML) was established. Computerized axial tomography (CT scanning) proved helpful in pointing toward the latter disorder. Clinical, neuropathological, and microbiologic features are presented. The diagnostic approach to central nervous system illness in patients with impaired immunocompetence should include consideration of simultaneous infection with multiple agents.

Central Nervous System Diseases↗

PubMed1998

Tumor pathogenesis of human neurotropic JC virus in the CNS.

In the last several years, studies have reported the detection of sequences similar to the polyomavirus, Simian Virus 40 (SV40) in human tumors including choroid plexus papillomas and ependymomas. Taken together with well-established evidence that SV40, as well as the human polyomaviruses JC virus (JCV) and BK virus (BKV), are oncogenic in several animal models, new interest has resurfaced regarding a possible role for these viruses in human tumors. In particular, a strong case can be made for re-evaluating the oncogenic potential of JCV in a neurotropic polyomavirus which is the causative agent of the fatal human demyelinating disease, Progressive Multifocal Leukoencephalopathy (PML). In this review, we discuss the transforming capability of JCV in vitro, JCV's ability to induce neural origin tumors in non-human primates as well as in rodents, and several case reports which suggest a possible role for JCV in tumor pathogenesis in the central nervous system.

Animals↗

PubMed1986

[Neurologic manifestations of the acquired immunodeficiency syndrome].

Recognition of the neurological symptoms and signs of the acquired immunodeficiency syndrome (AIDS) since 1982 has demonstrated the involvement of the nervous system in approximately one third of the cases. Certain opportunistic infections or tumors had been previously described in the course of immunodeficiency states of other origins: cerebral toxoplasmosis, cryptococcosis, progressive multifocal leukoencephalopathy, atypical mycobacteriosis and cerebral lymphoma. Other disorders such as subacute encephalitis raise specific etiopathogenic questions. Several of these affections can be associated or succeed each other and this is the natural course in AIDS. The detection of those conditions that are curable, among which toxoplasmosis, is of primary importance.

Acquired Immunodeficiency Syndrome↗

PubMed1998

Molecular biology and pathogenesis of human polyomavirus infections.

The two human polyomaviruses JC and BK are ubiquitous in the human population. Primary infection leads to lifelong persistence in the kidney, the CNS and in lymphoid cells. Virus is shed into the urine and is transmitted at least in part by the oral route. Under limited changes of the immunological state persistent polyomavirus infection is activated to an asymptomatic virus production. However, in severe long-lasting immunosuppression, highly effective virus multiplication can be accompanied by extended cytolytic damage of viral target cells leading to fatal disease. Whereas BKV is associated with severe urogenital disorders, JCV affects the CNS, leading to progressive multifocal leukoencephalopathy (PML). Although the number of PML cases is steadily increasing because of the AIDS epidemic, the mechanisms responsible for the change from asymptomatic-activated to the diseased state are not yet understood. As a possible pathogenic factor, the role of genomic heterogeneity of the transcriptional control region in the induction of disease is discussed.

BK Virus↗

PubMed1997

Neuroimaging of AIDS. I. Viral infections.

Viral infections of the brain and spinal cord cause significant morbidity and mortality in patients afflicted with AIDS. Debate continues over the specific mechanisms and pathways of how HIV-1 manifests itself in the brain and spinal cord. Attempts to predict which seropositive patients develop neurocognitive deficits caused by HIV-1 and how soon these deficits will occur in the course of disease have had limited success. The neuropathologic changes of HIV-1 must be distinguished from other viral infections, such as cytomegalovirus, JC papovavirus (progressive multifocal leukoencephalopathy), herpes simplex virus type 1, and varicella-zoster virus. In addition to cerebral spinal fluid sampling and serum testing, some specific features are seen with contrast-enhanced CT, MR imaging, proton MR spectroscopy, SPECT, and PET.

AIDS Dementia Complex↗

PubMedDate not supplied

CT of acquired immunodeficiency syndrome.

Thirty patients with acquired immunodeficiency syndrome were examined by computed tomography. In addition to systemic disease, these patients had a variety of neurologic symptoms and signs. Cerebral toxoplasmosis (six cases) was generally manifested by ring-enhancing lesions with surrounding decreased attenuation. Lymphoma (one case) exhibited a solid enhancing nodule, and progressive multifocal leukoencephalopathy (two cases) showed periventricular decreased attenuation. Atrophy (15 cases) was very common and invariably indicated a poor prognosis; the autopsy examinations of the latter cases showed degeneration of gray and white matter with features similar to cytomegalic inclusion encephalitis and subacute sclerosing encephalopathy of measles.

Acquired Immunodeficiency Syndrome↗

PubMed1978

Computerized cranial tomography in cerebral diseases of white matter.

Computerized tomographic scans were performed on 31 patients with primary diseases of the white matter. Among 18 patients with multiple sclerosis, acute lesions were visualized in five, all with symptomatic cerebral hemisphere disease. Characteristic white matter lesions were also demonstrated in adrenoleukodystrophy, spongiform encephalopathy, progressive multifocal leukoencephalopathy, disseminated necrotizing leukoencephalopathy, and an undiagnosed leukoencephalopathy associated with malignancy. Besides identifying white matter abnormalities, the CT scan patterns were often specific enough to help distinguish among the various etiologic possibilities for the abnormalities. Useful diagnostic characteristics included the anatomic distribution of lesions, mass effect, atrophic changes, and enhancement after contrast infusion.

Adrenal Insufficiency↗

PubMed2001

Aging and neuro-AIDS conditions and the changing spectrum of HIV-1-associated morbidity and mortality.

Older individuals (>50 years of age) now comprise over 11% of patients with AIDS in the United States. This percentage is expected to continue to grow, due both to the improved longevity of patients prescribed highly active antiretroviral therapy (HAART) and to new infections among older individuals. This review focuses on the neuropsychiatric and neurological conditions that are most likely to be affected by advancing age-HIV-1-associated cognitive-motor disorder, peripheral neuropathy, progressive multifocal leukoencephalopathy, primary CNS lymphoma, and risk for cerebrovascular accident. Age associations with incidence of these disorders and with treatment foci are specified. Implications for future changes in management are discussed.

Acquired Immunodeficiency Syndrome↗

PubMed1994

Expression of cytokines in brain lesions in subacute sclerosing panencephalitis.

We analyzed frozen brain specimens from three patients with subacute sclerosing panencephalitis (SSPE) for the presence of interleukin (IL)-1 beta, IL-2, IL-6, tumor necrosis factor (TNF), lymphotoxin (LT), and interferon (IFN)-gamma using immunocytochemical techniques. We detected these cytokines in SSPE brain lesions demonstrating extensive cellular infiltrates, demyelination, and gliosis. Double-label immunocytochemistry, using cell-specific markers, showed that positive immunoreactivity for these cytokines was present on both infiltrating cells and resident brain cells. We also found IL-6, TNF, and IFN-gamma at lower levels in brain tissue from a patient with progressive multifocal leukoencephalopathy. In contrast, normal control brain sections showed no reactivity for any of the cytokines. These findings indicate that IL-1 beta, IL-2, IL-6, TNT, LT, and IFN-gamma may be produced in SSPE lesions and may be involved in the lesion pathogenesis of SSPE.

Adult↗

PubMed2006

HIV disorders of the brain: pathology and pathogenesis.

Infection with HIV-1 has spread exponentially in recent years to reach alarming proportions. It is estimated than more than 33 million adults and 1.3 million children are infected worldwide. Approximately 16,000 new cases are diagnosed every day and almost 3 million people die every year from AIDS, making it the fourth leading cause of death in the world. Since the introduction of highly active anti-retroviral therapy (HAART) in the mid 1990s, the morbidity and mortality associated with HIV-1 infection has significantly decreased and AIDS has become a chronic disorder. However, neuropathological conditions associated with AIDS are still present in approximately 70 to 90% of patients and can be the result of HIV itself or of opportunistic infections. Here we briefly review the pathology and pathophysiology of AIDS-Encephalopathy, of some of the significant opportunistic infections affecting the brain in the context of AIDS, including Progressive Multifocal Leukoencephalopathy (PML) a demyelinating disease caused by the human neurotropic JC virus, Toxoplasmosis, Cryptococcosis and of primary CNS lymphoma, a brain malignancy frequently associated with HIV-1 infection, all of them considered AIDS defining conditions.

AIDS-Related Opportunistic Infections↗

PubMed1979

New oncogenic human papovaviruses.

Human papovaviruses of the polyoma-SV40 subgroup are common infectious agents. The clinical picture of the primary infection of these viruses is unknown, but one of the viruses, the JC virus, is associated with and probably causes progressive multifocal leukoencephalopathy. These viruses cause tumours and transform cells of several species of laboratory animals. Current results seem to rule them out as a major aetiollogical factor in human cancer. However, their relationship to human tumours requires further study, especially in immunologically compromised patients showing activation of a latent infection.

Animals↗

PubMed1997

Neuroimaging--autopsy correlations in AIDS.

This article is a brief review of the radiologic-pathologic correlation of central nervous lesions occurring in patients with AIDS. The major discussions of the imaging appearance and radiologic differential diagnosis have been presented elsewhere in this issue. Our emphasis is on the gross pathologic correlations that are only possible with autopsy materials. We will illustrate the opportunistic neoplasms such as primary CNS lymphoma. This article also discusses the imaging and pathology of the common opportunistic infections. Toxoplasmosis, an obligate intracellular protozoan, is the most common CNS infection producing a mass lesion in AIDS. However, AIDS encephalitis, a direct infection of the brain by the HIV-1 virus itself, may actually be more prevalent. Other viral infections occurring in AIDS include progressive multifocal leukoencephalopathy. Fungal diseases infecting the central nervous system of AIDS patients include cryptococcus, aspergillosis, and mucormycosis. The primary purpose of this article is to demonstrate how the gross pathology correlates with the radiologic images.

AIDS Dementia Complex↗

PubMed1998

HIV-associated PML presenting as epilepsia partialis continua.

Two patients with human immunodeficiency virus (HIV) type 1 infection presented new-onset epilepsia partialis continua (EPC) as an early manifestation of progressive multifocal leukoencephalopathy (PML). EPC occurred with no other seizures and was associated with negative radiographic and electrophysiological findings for several weeks. PML represents an increasingly recognized cause of new-onset seizures in both seropositive and seronegative patients, with no report of EPC as a presenting complaint.

AIDS Dementia Complex↗

PubMed1994

Fulminant bilateral cerebellar syndrome in a patient with chronic lymphocytic leukemia.

A 55 year old patient with chronic lymphocytic leukemia (CLL) and long-standing excessive lymphocytosis developed a rapidly progressive neurological syndrome. Differential diagnosis focused on two rate neurological complications in this disease: direct brain infiltration by leukemic cells versus progressive multifocal leukoencephalopathy (PML). Tissue diagnosis was not available. Two cerebro-spinal fluid examinations performed during the presence of the acute neurological symptoms were normal. Computed tomography (CT) showed low density lesions without enhancement and no mass effect within the left cerebellum. Magnetic resonance imaging scan (MRI) demonstrated multiple hyperintense areas in the brain stem, right and left cerebellum and right capsula interna, suggestive of demyelinative process. In our opinion these findings were compatible with the diagnosis of PML, but biopsy was not performed. Because of the different therapeutic approach in these two conditions, we feel that tissue diagnosis is warranted in patients with CLL who develop a rapidly progressive central nervous system complication in the presence of normal CSF.

Diagnosis, Differential↗

PubMedDate not supplied

Neurologic disorders associated with AIDS retroviral infection.

Neurologic disease occurs frequently in patients infected with the human immunodeficiency virus (HIV), and a large body of literature now exists detailing the various infections, neoplasms, and other conditions that can affect the central nervous system (CNS) or the peripheral nervous system in children and adults with AIDS, persistent generalized lymphadenopathy, or (in some cases) only serologic evidence of retroviral infection. Although certain opportunistic infections (toxoplasmosis, cryptococcosis, progressive multifocal leukoencephalopathy, and herpesviral infections) and CNS lymphomas often produce CNS disease in patients with AIDS, it is now clear that many cases of neurologic disease are caused by a group of disorders thought to be related to direct CNS infection by the AIDS retrovirus. Disease of the peripheral nervous system is also being increasingly recognized; some cases probably have an autoimmune basis.

Acquired Immunodeficiency Syndrome↗