Treatment options for AIDS patients with progressive multifocal leukoencephalopathy

Treatment options for progressive multifocal leukoencephalopathy in HIV-infected persons: current status and future directions

Progressive multifocal encephalopathy (PML) caused by JC virus was frequently encountered in AIDS patients before combination antiretroviral therapy (cART). Incidence decreased and the outcome improved with cART. The immune reconstitution with cART is beneficial for HIV-infected patients and is an effective treatment for PML. However, when it is excessive an inflammatory response immune syndrome might occur with deterioration of PML. So far, no specific therapy has proven efficacious in small clinical trials in spite of some optimistic case reports. Combination of drugs targeted at different stages of JC virus life cycle seems to have a better effect. Passive and active immune therapies, immune competence "boosters" appear promising. New future approaches such as gene editing are not far away.

Progressive multifocal leukoencephalopathy complicating untreated chronic lymphatic leukemia: case report and review of the literature

A 58-year old female with a four-year history of previously untreated CLL at Binet stage A complained about word finding problems, impaired vision, and gait unsteadiness. Concerning her CLL she was asymptomatic and had never required any specific treatment. Her neurological examination disclosed cognitive alterations, homonyme hemianopia to the right, aphasia, and mild right-sided hemiparesis. Cerebral MRI showed a hyperintense lesion on T2 weighted images without contrast enhancement. CSF examination revealed normal findings, including CSF protein, cell count, cytology and PCR-analysis was negative for the presence of JC virus DNA. On follow-up MRI, performed 2 weeks later, the T2 lesion was further enlarging. Subsequent stereotactic brain biopsy was diagnostic for PML revealing abnormal oligodendrocytes staining positive against antibodies specific for simian vacuolating virus 40. In addition, repeated CSF analyses for JC-Virus DNA in the course of the disease became positive. After confirmation of diagnosis treatment with mirtazapine (30 mg/d) and mefloquine (250 mg/d) was initiated. Rapid clinical progression correlated to further worsening on MRI. Therefore this treatment was terminated after 16 days and the regime was changed to a five-day courses of cytarabine (2 mg/kg/d) combined with intrathecal administration of liposomal cytarabine (50 mg). Due to further clinical progression with global aphasia, blindness and severe right-sided hemiparesia, medication was stopped. The Patient died three and a half months after onset of symptoms.

Therapy and prophylaxis of opportunistic infections in HIV-infected patients: a guideline by the German and Austrian AIDS societies (DAIG/ÖAG) (AWMF 055/066)

INTRODUCTION

There was a growing need for practical guidelines for the most common OIs in Germany and Austria under consideration of the local epidemiological conditions.

MATERIALS AND METHODS

The German and Austrian AIDS societies developed these guidelines between March 2010 and November 2011. A structured Medline research was performed for 12 diseases, namely Immune reconstitution inflammatory syndrome, Pneumocystis jiroveci pneumonia, cerebral toxoplasmosis, cytomegalovirus manifestations, candidiasis, herpes simplex virus infections, varizella zoster virus infections, progressive multifocal leucencephalopathy, cryptosporidiosis, cryptococcosis, nontuberculosis mycobacteria infections and tuberculosis. Due to the lack of evidence by randomized controlled trials, part of the guidelines reflects expert opinions. The German version was accepted by the German and Austrian AIDS Societies and was previously published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF; German Association of the Scientific Medical Societies).

CONCLUSION

The review presented here is a translation of a short version of the German-Austrian Guidelines of opportunistic infections in HIV patients. These guidelines are well-accepted in a clinical setting in both Germany and Austria. They lead to a similar treatment of a heterogeneous group of patients in these countries.

Central Nervous System Infections

Central nervous system (CNS) infections—i.e., infections involving the brain (cerebrum and cerebellum), spinal cord, optic nerves, and their covering membranes—are medical emergencies that are associated with substantial morbidity, mortality, or long-term sequelae that may have catastrophic implications for the quality of life of affected individuals. Acute CNS infections that warrant neurointensive care (ICU) admission fall broadly into three categories—meningitis, encephalitis, and abscesses—and generally result from blood-borne spread of the respective microorganisms. Other causes of CNS infections include head trauma resulting in fractures at the base of the skull or the cribriform plate that can lead to an opening between the CNS and the sinuses, mastoid, the middle ear, or the nasopharynx. Extrinsic contamination of the CNS can occur intraoperatively during neurosurgical procedures. Also, implanted medical devices or adjunct hardware (e.g., shunts, ventriculostomies, or external drainage tubes) and congenital malformations (e.g., spina bifida or sinus tracts) can become colonized and serve as sources or foci of infection. Viruses, such as rabies, herpes simplex virus, or polioviruses, can spread to the CNS via intraneural pathways resulting in encephalitis. If infection occurs at sites (e.g., middle ear or mastoid) contiguous with the CNS, infection may spread directly into the CNS causing brain abscesses; alternatively, the organism may reach the CNS indirectly via venous drainage or the sheaths of cranial and spinal nerves. Abscesses also may become localized in the subdural or epidural spaces. Meningitis results if bacteria spread directly from an abscess to the subarachnoid space. CNS abscesses may be a result of pyogenic meningitis or from septic emboli associated with endocarditis, lung abscess, or other serious purulent infections. Breaches of the blood–brain barrier (BBB) can result in CNS infections. Causes of such breaches include damage (e.g., microhemorrhage or necrosis of surrounding tissue) to the BBB; mechanical obstruction of microvessels by parasitized red blood cells, leukocytes, or platelets; overproduction of cytokines that degrade tight junction proteins; or microbe-specific interactions with the BBB that facilitate transcellular passage of the microorganism. The microorganisms that cause CNS infections include a wide range of bacteria, mycobacteria, yeasts, fungi, viruses, spirochaetes (e.g., neurosyphilis), and parasites (e.g., cerebral malaria and strongyloidiasis). The clinical picture of the various infections can be nonspecific or characterized by distinct, recognizable clinical syndromes. At some juncture, individuals with severe acute CNS infections require critical care management that warrants neuro-ICU admission. The implications for CNS infections are serious and complex and include the increased human and material resources necessary to manage very sick patients, the difficulties in triaging patients with vague or mild symptoms, and ascertaining the precise cause and degree of CNS involvement at the time of admission to the neuro-ICU. This chapter addresses a wide range of severe CNS infections that are better managed in the neuro-ICU. Topics covered include the medical epidemiology of the respective CNS infection; discussions of the relevant neuroanatomy and blood supply (essential for understanding the pathogenesis of CNS infections) and pathophysiology; symptoms and signs; diagnostic procedures, including essential neuroimaging studies; therapeutic options, including empirical therapy where indicated; and the perennial issue of the utility and effectiveness of steroid therapy for certain CNS infections. Finally, therapeutic options and alternatives are discussed, including the choices of antimicrobial agents best able to cross the BBB, supportive therapy, and prognosis.

Molecular biology, epidemiology, and pathogenesis of progressive multifocal leukoencephalopathy, the JC virus-induced demyelinating disease of the human brain

Progressive multifocal leukoencephalopathy (PML) is a debilitating and frequently fatal central nervous system (CNS) demyelinating disease caused by JC virus (JCV), for which there is currently no effective treatment. Lytic infection of oligodendrocytes in the brain leads to their eventual destruction and progressive demyelination, resulting in multiple foci of lesions in the white matter of the brain. Before the mid-1980s, PML was a relatively rare disease, reported to occur primarily in those with underlying neoplastic conditions affecting immune function and, more rarely, in allograft recipients receiving immunosuppressive drugs. However, with the onset of the AIDS pandemic, the incidence of PML has increased dramatically. Approximately 3 to 5% of HIV-infected individuals will develop PML, which is classified as an AIDS-defining illness. In addition, the recent advent of humanized monoclonal antibody therapy for the treatment of autoimmune inflammatory diseases such as multiple sclerosis (MS) and Crohn's disease has also led to an increased risk of PML as a side effect of immunotherapy. Thus, the study of JCV and the elucidation of the underlying causes of PML are important and active areas of research that may lead to new insights into immune function and host antiviral defense, as well as to potential new therapies.

[Progressive multifocal leukoencephalopathy (PML)]

Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of latently infected JCV when hosts' immune system is impaired by HIV infection, hematologic diseases, collagen diseases, immunemodulatory therapy and so on. PML was rare but HIV infection and Natalizumab have made it much more common while the prognosis is much better than other PML. PML patients present with various signs and symptoms including hemiparesis, dementia, aphasia, visual disturbance, cranial nerve paresis, cerebellar signs and bladder bowel disturbance. Brain MRI reveals characteristic demyelinating lesions in the CNS white matter and CSF mild increase of protein with or without mild mononuclear pleocytosis. Detection of JCV genome from CSF is crucial for the clinical diagnosis of PML. PML was once thought to be fatal but some HIV infected PML patients showed halting progression or even recovery after introduction of HAART. In addition, anti-malarial drug mefloquine was found to be effective. Recovery of immunity may provoke some inflammatory responses known as immune reconstruction inflammatory syndrome (IRIS) which requires high dose corticosteroid. In Japan, we are providing free test of CSF-JCV genome and organized a unique system for surveillance and clinical research of PML. Using this system we hope to improve diagnosis and therapy of PML in Japan.

Progressive multifocal leukoencephalopathy: clinical and molecular aspects

The fatal CNS demyelinating disease, progressive multifocal leukoencephalopathy (PML), is rare and appears to occur almost always as a consequence of immune dysfunction. Thus, it is associated with HIV/AIDS and also as a side effect of certain immunomodulatory monoclonal antibody therapies. In contrast to the rarity of PML, the etiological agent of the disease, the polyomavirus JC (JCV), is widespread in populations worldwide. In the 40 years since JCV was first isolated, much has been learned about the virus and the disease from laboratory and clinical observations. However, there are many aspects of the viral life cycle and of the pathogenesis of the disease that remain unclear, and our understanding is constantly evolving. In this review, we will discuss our current understanding of the clinical features of PML and molecular characteristics of JCV and of how they relate to each other. Clinical observations can inform molecular studies of the virus, and likewise, molecular findings concerning the life cycle of the virus can guide the development of novel therapeutic strategies.

Progressive multifocal leukoencephalopathy: what's new?

Progressive multifocal leukoencephalopathy (PML), a severe demyelinating disease that is caused by human JC polyomavirus, was first described as a complication of immune suppression 50 years ago and emerged as a major complication of HIV infection in the 1980s. The prognosis has remained dismal since then, with discouraging results from clinical trials of various therapeutic approaches, including immunomodulation and/or inhibition of viral replication. PML is caused by reactivation of latent JC virus, and serotonergic 5-HT(2a) receptors have been identified as being critical for viral infection of glial cells. In recent years, immunosuppressive therapeutic antibodies have been associated with an increased incidence rate of PML. Here, the authors review findings on the pathogenesis of PML and the encouraging case reports of novel treatments.

WU Polyomavirus (WUPyV): A Recently Detected Virus Causing Respiratory Disease?

The WU polyomavirus (WUPyV) is a novel member of the family Polyomaviridae recently detected in respiratory tract specimens by shotgun sequencing. Intriguingly, viral genome has been detected in 0.4% to 11.5% of respiratory tract specimens from children with respiratory disease. The levels of co-infection with established respiratory viruses were in the range between 30.8% and 91.7%. Moreover, some studies report detection of WUPyV in stool or serum. So far, WUPyV infections can not be distinguished from other viral infections by means of clinical symptoms. Respiratory tract disease like pneumonia or bronchitis is frequently observed in patients harbouring WUPyV. Detection of viremia suggests systemic infections. However, the available data do not prove WUPyV to be a human pathogen. Further investigations are necessary.