Diagnostic criteria and clinical procedures in HIV-1 associated progressive multifocal leukoencephalopathy

Magnetic resonance imaging may simulate progressive multifocal leucoencephalopathy in a patient with chronic lymphocytic leukemia after fludarabine therapy

A 60-year-old male with chronic lymphatic leukemia (CLL) after 6 months of fludarabine therapy was admitted with status epilepticus and developed left hemiplegia. His magnetic resonance imaging revealed multiple T2 hyperintense lesions in the right frontal and left parieto-occipital lesion, simulating progressive multifocal leucoencephalopathy (PML). Cerebrospinal fluid Polymerase Chain Reaction (PCR) for JC virus was negative. We suggest the possible role of fludarabine in producing PML-like lesions in patients with Chronic Lymphocytic Leukemia (CLL).

Polyomaviruses and human diseases

Polyomaviruses are small, nonenveloped DNA viruses, which are widespread in nature. In immunocompetent hosts, the viruses remain latent after primary infection. With few exceptions, illnesses associated with these viruses occur in times of immune compromise, especially in conditions that bring about T cell deficiency. The human polyomaviruses BKV and JCV are known to cause, respectively, hemorrhagic cystitis in recipients of bone marrow transplantation and progressive multifocal leukoencephalopathy in immunocompromised patients, for example, by HIV infection. Recently, transplant nephropathy due to BKV infection has been increasingly recognized as the cause for renal allograft failure. Quantitation of polyomavirus DNA in the blood, cerebrospinal fluid, and urine, identification of virus laden "decoy cells" in urine, and histopathologic demonstration of viral inclusions in the brain parenchyma and renal tubules are the applicable diagnostic methods. Genomic sequences of polyomaviruses have been reported to be associated with various neoplastic disorders and autoimmune conditions. While various antiviral agents have been tried to treat polyomavirus-related illnesses, current management aims at the modification and/or improvement in the hosts' immune status. In this chapter, we provide an overview of polyomaviruses and briefly introduce its association with human diseases, which will be covered extensively in other chapters by experts in the field.

Visual loss secondary to acquired immunodeficiency virus–related progressive multifocal leukoencephalopathy demonstrating clinical improvement with highly active antiretroviral therapy

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a demyelinating brain disease caused by the JC papovavirus. This disease afflicts the immunocompromised, particularly those infected with the human immunodeficiency virus (HIV). PML progresses rapidly, causing a variety of visual and neurologic complications.

CASE REPORT

A 49-year-old HIV-positive man presented with reduced vision, a bilateral left hemianopsia, left-sided motor dysfunction, and mild dementia. Confirmation of the presence of the JC virus in the cerebrospinal fluid and characteristic computed tomography and magnetic resonance imaging changes led to the diagnosis of PML. No treatment was initiated other than continuation of highly active antiretroviral therapy (HAART). The patient was re-examined 8 months later and found to have significant resolution of his visual and neurological symptoms.

CONCLUSION

PML often results in devastating and deadly neurologic deterioration in HIV-positive patients. Although treatment options are limited, HAART can lead to clinical improvement of symptoms and prolong survival time.

Infectious CNS disease as a differential diagnosis in systemic rheumatic diseases: three case reports and a review of the literature

BACKGROUND

Immunosuppressive treatment of rheumatic diseases may be associated with several opportunistic infections of the brain. The differentiation between primary central nervous system (CNS) involvement and CNS infection may be difficult, leading to delayed diagnosis.

OBJECTIVE

To differentiate between CNS involvement and CNS infection in systemic rheumatic diseases.

METHODS AND RESULTS

Three patients with either longstanding or suspected systemic rheumatic diseases (systemic lupus erythematodes, Wegener's granulomatosis, and cerebral vasculitis) who presented with various neuropsychiatric symptoms are described. All three patients were pretreated with different immunosuppressive drugs (leflunomide, methotrexate, cyclophosphamide) in combination with corticosteroids. Magnetic resonance imaging of the brain was suggestive of infectious disease, which was confirmed by cerebrospinal fluid analysis or stereotactic brain biopsy (progressive multifocal leucoencephalopathy (PML) in two and nocardiosis in one patient).

DISCUSSION

More than 20 cases of PML or cerebral nocardiosis in patients receiving corticosteroids and cytotoxic drugs for rheumatic disease have been reported. The clinical aspects of opportunistic CNS infections and the role of brain imaging, cerebrospinal fluid analysis and stereotactic brain biopsy in the differential diagnosis are reviewed.

Progressive multifocal leukoencephalopathy in chronic lymphocytic leukemia after treatment with fludarabine

A 65-year-old man with chronic lymphocytic leukemia (CLL) diagnosed 11 years ago and treated with standard dose of fludarabine developed a rapidly fatal progressive neurological syndrome. Differential diagnoses included brain infiltration by CLL as opposed to progressive multifocal leukoencephalopathy (PML). A magnetic resonance imaging (MRI) scan showed a hyperintense T2-weighted signal in the left frontal region. Cerebro-spinal fluid polymerase chain reaction (PCR) was positive for virus JC (JCV). These findings were compatible with the diagnosis of PML. Fludarabine has been used to treat acute leukemias, CLL and follicular lymphomas. Its toxicity includes myelosuppression, immunosuppression and sporadic life-threatening neurotoxicity, although standard doses of it are considered safe. Late-onset fatal cerebral dysfunction caused by JCV after standard-dose fludarabine has been described previously. The widespread and increasing use of fludarabine makes it interesting to define the potential of standard doses of fludarabine for causing severe neurological side-effects such as PML.

Isolated pontine progressive multifocal leukoencephalopathy: unusual magnetic resonance imaging features

Progressive multifocal leukoencephalopathy (PML) is an uncommon opportunistic infection that causes focal or multifocal demyelination predominantly in the subcortical white matter. The authors describe the clinical and radiographic features in 2 unusual cases of PML that were initially isolated to the pons. One patient presented clinically with only an isolated sixth cranial nerve palsy.

Progressive Multifocal Leukoencephalopathy

Progressive multifocal leukoencephalopathy is a subacute demyelinating disease that occurs in patients with defects in cell-mediated immunity, including those with AIDS and lymphoproliferative disorders. It is caused by reactivation of JC virus (JCV), which infects 70% to 90% of the population by adulthood, but remains latent in normal hosts. Once reactivated, JCV infects oligodendrocytes and astrocytes, with resultant cell lysis, leading to focal areas of demyelination and necrosis in cerebral white matter causing focal neurologic deficits and characteristic findings on MRI. Polymerase chain reaction for the detection of JCV is a sensitive and specific test, replacing brain biopsy as the initial diagnostic test in the appropriate clinical setting. Historically, the prognosis of progressive multifocal leukoencephalopathy is poor, with most patients dying within 6 months of diagnosis. Antiviral medications targeted against JCV have shown little success. However, with the use of highly active antiretroviral therapy, survival of AIDS patients with progressive multifocal leukoencephalopathy has improved.

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.

Progressive multifocal leukoencephalopathy in a patient with acquired immunodeficiency syndrome (AIDS) manifesting Gerstmann's syndrome

We reported a case of acquired immunodeficiency syndrome (AIDS) via multiple blood transfusions, who manifested progressive multifocal leukoencephalopathy (PML) about 18 months after the development of AIDS. PML initiated with right hemiparesis, dysphasia, and Gerstmann's syndrome and resulted in death within 2 months after the onset. Neuroimaging examinations revealed white matter lesions mainly in the left posterior parietal lobe. The cortical gray matter also showed abnormal signal intensity. Peripheral CD4+ lymphocyte count was 81/microl. Routine cerebrospinal fluid (CSF) examinations were negative. CSF antibodies against herpes simplex virus, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus as well as serum antibody against toxoplasma gondii were negative. Though autopsy or biopsy of the brain was not performed, JC virus genomes were detected in the CSF sample by a polymerase chain reaction, and their sequencing showed unique alterations of the regulatory regions, characteristic to PML-type JC virus.