Human immunodeficiency virus-associated progressive multifocal leucoencephalopathy: epidemiology and predictive factors for prolonged survival

Continued declining incidence and improved survival of progressive multifocal leukoencephalopathy in HIV/AIDS patients in the current era

To evaluate the situation and perspectives of progressive multifocal leukoencephalopathy (PML) in human immunodeficiency virus (HIV)-infected patients, we investigated changes in the incidence, causes, and long-term outcome of this disease in 72 acquired immunodeficiency syndrome (AIDS) patients who were diagnosed with PML from 1996 to 2011. Patients were classified according to the date of diagnosis in the first (1996-2000, n = 35), second (2001-2006, n = 26), and recent or third highly active antiretroviral therapy (HAART) period (2007-2011, n = 11). Overall, the incidence of PML decreased from 14.8 cases/1,000 patients/year in 1996 to 2.6 in 2005 and 0.8 in 2011, and nearly two-thirds of recent cases (64 %) were observed in HIV patients not attending clinical visits. The baseline median CD4+ count was higher in recently PML-diagnosed patients (77 vs. 86 vs. 101 cells/mm(3); p < 0.01), and this fact was associated with a cerebrospinal fluid (CSF) inflammatory profile (from 11 to 31 to 55 %, p = 0.007) and with a significantly longer survival (attributable death, 54 vs. 35 vs. 36 %, respectively, p < 0.01). Thus, the overall 1-year and 3-year survival rates were 55 and 50 %, respectively, increasing to 79 % at 1 year for patients with CD4+ count above 100 cells/mm(3) at diagnosis. In a Cox regression analysis, an older age (hazard ratio, HR 0.76), a baseline CD4+ count above 100 cells/mm(3) (HR 0.33), and a CSF inflammatory profile (HR 0.12) were significantly associated with a longer survival. The clinical presentation and outcome of PML in AIDS patients continue to change dramatically. Now, a declining incidence and long-term survival is observed.

Characteristics of progressive multifocal leukoencephalopathy clarified through internet-assisted laboratory surveillance in Japan

Background

Progressive multifocal leukoencephalopathy (PML), a rare but fatal demyelinating disease caused by JC virus (JCV), occurs mainly in immunocompromised patients. As PML develops in individuals with various underlying disorders sporadically and infrequently, a nationwide survey of PML is difficult. This study was conducted to elucidate the characteristics of PML in Japan through an internet-assisted laboratory surveillance program.

Methods

A diagnostic support system for PML was established using a real-time PCR assay of JCV DNA in cerebrospinal fluid (CSF), and requests for testing were received from clinicians via specialized websites. Medical histories of patients were collected through standardized questionnaires, and a database of CSF JCV loads and clinical information was created and analyzed.

Results

For 4 years from April 2007 to March 2011, CSF specimens from 419 patients were tested. Forty-eight individuals were found positive for JCV DNA in their CSF and were diagnosed with PML. PML primarily occurred not only in HIV-positive patients (33.3%) but also in patients with hematologic disorders after receiving stem cell transplantation, chemotherapy, and/or immunosuppressive treatment (39.6%). The frequencies of PML cases among the subjects in these two categories were 20.3% and 23.5%, respectively. Although no significant features were observed with respect to CSF JCV loads in PML patients with an HIV infection or hematologic disorder, males were predominant in both groups (100% and 89.5%, respectively). The proportion of PML cases with autoimmune disorders (6.3%) or solid-organ transplants (2.1%) was smaller than those with HIV infection or hematologic disorders, probably due to the limited availability of therapeutic monoclonal antibodies and transplantation from brain dead donors.

Conclusions

The results suggest that the internet-assisted laboratory surveillance program might be a useful strategy for collecting precise real-time information on PML on a national level. The current database provides important background information for the diagnosis and treatment of patients with risk factors for PML.

Human polyomaviruses JC and BK in the urine of Brazilian children and adolescents vertically infected by HIV

The aim of this study was to characterize the urinary excretion of the BK (BKV) and JC (JCV) human polyomaviruses in a cohort of human immunodeficiency virus (HIV)-infected children and adolescents. One hundred and fifty-six patients were enrolled: Group I included 116 HIV-infected children and adolescents [median age = 11.4 years (y); range 1-22 y]; Group II included 40 non-HIV-infected healthy controls (median age = 11.37 y; range 7-16 y). Single urine samples from both groups were screened for the presence of JCV and BKV DNA by polymerase chain reaction at enrolment. The overall rate of JCV and BKV urinary excretion was found to be 24.4% and 40.4%, respectively (n = 156). Group I had urinary excretion of JCV and BKV in 27.6% and 54.3% of subjects, respectively. In contrast, Group II showed positive results for JCV in 17.5% of subjects and for BKV in 12.5% of subjects (p Pearson JCV = 0.20; p Pearson BKV < 0.0001). In Group I, there was no association between JCV/BKV shedding and age, gender or CD4 values. Patients with an HIV viral load < 50 copies/mL had a lower excretion of BKV (p < 0.001) and a trend of lower JCV excretion (p = 0.07). One patient in Group I (1/116, 0.9%) showed clinical and radiological features consistent with progressive multifocal leukoencephalopathy, suggesting that children with HIV/polyomavirus coinfection should be kept under surveillance.

Plasma levels of JC virus are sensitive and specific for detecting and predicting progressive multifocal leukoencephalopathy in HIV patients

Aims: HIV-1 infection represents the most common immunosuppressive condition associated with progressive multifocal leukoencephalopathy (PML). Materials & methods: Nested PCR and quantitative real-time PCR (qPCR) for JC virus (JCV) DNA was performed on serial plasma samples obtained from 14 HIV patients with PML and 27 matched controls. Results: JCV large T antigen (LT) DNA was detected via qPCR in 11 out of 14 (79%) PML patients at disease onset and four out of 27 (15%) controls (p < 0.001). JCV LT qPCR was associated with PML diagnosis, duration of known HIV infection, absence of a prior AIDS-defining illness and absence of combination antiretroviral therapy (p < 0.001; R2 = 0.35). JCV LT qPCR was more likely to be positive in the 8 months prior to PML diagnosis compared with earlier samples (p = 0.01). Conclusion: Detection of JCV DNA in plasma of HIV infected patients via qPCR may represent a valuable test for identifying patients at risk of developing PML.

[Demyelinating disorders]

Leukoencephalopathies in adults are frequent and exhibit highly variable aetiology, including multiple acquired causes such as inflammatory, vascular or toxic diseases and neoplasias. In contrast leukodystrophies are genetically determined, chronic progressive myelin disorders with a variable pathogenetic background and a great diversity of clinical and paraclinical findings. Some diseases, namely those with an additional inborn error of metabolism, are treatable. Genetic counselling appears to be of major importance for patients and their families. In the light of numerous acquired adulthood leukoencephalopathies a clear delineation of late-onset genetic leukodystrophies is necessary. Clinical symptoms and MRI patterns of some of the major leukodystrophies are reported, including possibilities of biochemical and genetic testing.

[Infections of the central nervous system in the immuno-compromised]

Infections of the central nervous system (CNS) can be caused by a variety of pathogens, depending on whether the number and function of T-cells or monocytes are impaired (as in HIV patients) or whether the number and function of polymorphonuclear granulocytes are reduced or impaired, as typically seen in patients on immunosuppressive therapy, post transplantation, etc.. The first part of the chapter deals with CNS infections associated with reduced or abnormal T-cell (or monocytic) function and number, mainly seen in HIV patients, such as cerebral toxoplasmosis, CNS cryptococcosis, cytomegalovirus encephalitis, and progressive multifocal leukoencephalopathy. The clinical presentation, diagnostic procedures, as well as therapeutic and prophylactic management of these diseases are described in detail. The second part of the chapter deals with diseases usually seen in patients with impaired or reduced number and function of polymorphonuclear granulocytes. Such CNS infections are frequently caused by viral, bacterial, or fungal pathogens and are described in their clinical presentation, their diagnostic procedures and the best possible therapeutic and prophylactic management.