Progressive multifocal leukoencephalopathy in pediatric patients: case report and literature review

Progressive Multifocal Leukoencephalopathy confined to the posterior fossa as the presenting manifestation of HIV in a paediatric patient

Progressive Multifocal Leukoencephalopathy (PML), primarily affecting immunocompromised individuals due to the John Cunningham virus (JC), is common in HIV-positive adults but rare in paediatrics. We present a unique case of a 14-year-old female with PML as the initial manifestation of HIV, with MRI lesions isolated to the posterior fossa. Initial symptoms included fever and rash, progressing to neurological deficits and ataxia. Severe immune suppression due to HIV and JC virus in the cerebrospinal fluid were confirmed. Management included immune reconstitution therapy (antiretroviral treatment) and supportive care. Despite interventions, the patient had a slow recovery with significant residual neurological sequelae. Timely recognition of Immune Reconstitution Inflammatory Syndrome (IRIS) and steroid initiation proved helpful. Antiretroviral therapy improved the survival rate of HIV-related PML, but long-term neurological sequelae, especially in posterior fossa cases, significantly impact the patient's quality of life. This case highlights diagnostic and treatment challenges in paediatric PML, particularly with atypical lesions location.

A review of movement disorders in persons living with HIV

BACKGROUND

The human immunodeficiency virus (HIV) causes movement disorders in persons living with HIV (PLH).

OBJECTIVES AND METHODS

We conducted a systematic review on the spectrum of movement disorders in PLH using standard terms for each of the phenomenologies and HIV.

RESULTS

Movement disorders in PLH were commonly attributed to opportunistic infections (OI), dopamine receptor blockade reactions, HIV-associated dementia (HAD), presented during seroconversion, developed due to drug reactions or antiretroviral therapy (ART) itself and lastly, movement disorders occurred as a consequence of the HIV-virus. Parkinsonism in ART naïve PLH was associated with shorter survival, however when Parkinsonism presented in PLH on ART, the syndrome was indistinguishable from Idiopathic Parkinson's disease and responded to therapy. Tremor was often postural due to HAD, drugs or OI. Generalized chorea was most frequent in HIV encephalopathy and toxoplasmosis gondii caused most cases of hemichorea. Ataxia was strongly associated with JCV infection, ART efavirenz toxicity or due to HIV itself. Dystonia was reported in HAD, secondary to drugs and atypical facial dystonias. Both cortical/subcortical and segmental/spinal origin myoclonus were noted mainly associated with HAD. In patients with HIV related opsoclonus-myoclonus-ataxia-syndrome, seroconversion illness was the commonest cause of followed by IRIS and CSF HIV viral escape phenomenon.

CONCLUSIONS

Aetiology of movement disorders in PLH depend on the treatment state. Untreated, PLH are prone to develop OI and HAD and movement disorders. However, as the number of PLH on ART increase and survive longer, the frequency of ART and non-AIDS related complications are likely to increase.

Nationwide Laboratory Surveillance of Progressive Multifocal Leukoencephalopathy in Japan: Fiscal Years 2011-2020

Progressive multifocal leukoencephalopathy (PML) is a devastating demyelinating disease caused by JC virus (JCV), predominantly affecting patients with impaired cellular immunity. PML is a non-reportable disease with a few exceptions, making national surveillance difficult. In Japan, polymerase chain reaction (PCR) testing for JCV in the cerebrospinal fluid (CSF) is performed at the National Institute of Infectious Diseases to support PML diagnosis. To clarify the overall profile of PML in Japan, patient data provided at the time of CSF-JCV testing over 10 years (FY2011-2020) were analyzed. PCR testing for 1537 new suspected PML cases was conducted, and 288 (18.7%) patients tested positive for CSF-JCV. An analysis of the clinical information on all individuals tested revealed characteristics of PML cases, including the geographic distribution, age and sex patterns, and CSF-JCV-positivity rates among the study subjects for each type of underlying condition. During the last five years of the study period, a surveillance system utilizing ultrasensitive PCR testing and widespread clinical attention to PML led to the detection of CSF-JCV in the earlier stages of the disease. The results of this study will provide valuable information not only for PML diagnosis, but also for the treatment of PML-predisposing conditions.

Non-congenital viral infections of the central nervous system: from the immunocompetent to the immunocompromised child

Non-congenital viral infections of the central nervous system in children can represent a severe clinical condition that needs a prompt diagnosis and management. However, the aetiological diagnosis can be challenging because symptoms are often nonspecific and cerebrospinal fluid analysis is not always diagnostic. In this context, neuroimaging represents a helpful tool, even though radiologic patterns sometimes overlap. The purpose of this pictorial essay is to suggest a schematic representation of different radiologic patterns of non-congenital viral encephalomyelitis based on the predominant viral tropism and vulnerability of specific regions: cortical grey matter, deep grey matter, white matter, brainstem, cerebellum and spine.

Human immunodeficiency virus-related cerebral white matter disease in children

The human immunodeficiency virus (HIV) epidemic seems largely controlled by anti-retroviral treatment with resultant large numbers of children growing up with the disease on long-term treatment, placing them at higher risk to develop HIV-related brain injury, ongoing cognitive impairment and treatment-related neurological complications. Cerebral white matter involvement is a common radiologic finding in HIV infection and the causes of this have overlapping appearances, ranging from diffuse widespread involvement to focal lesions. The varied pathophysiology is broadly grouped into primary effects of HIV, opportunistic infection, vascular disease and neoplasms. White matter changes in children can be different from those in adults. This review provides guidance to radiologists with the diagnostic dilemma of nonspecific cerebral white matter lesions in children with HIV. The authors discuss common causes of HIV-related cerebral white matter disease as well as the role of neuroimaging in the management of these children.

Infections

"Children are not little adults," and while this is a well-worn aphorism, it is especially true in the context of infection, where the same organism may evoke a different immune response in the pediatric central nervous system (CNS) and clinical presentation may be clouded by the lack of a good history or paucity of clinical information. The chronology and natural history of different organisms/infections will be laid out together with the preferred use of different imaging modalities. This chapter will use illustrative examples of some of the more common infections and their complications, in addition to several more rare conditions as well as mimics of childhood CNS infection. Challenges in the imaging of children, including strategies to minimize the use of radiation, are discussed. Some of the more recently voiced concerns regarding the use of anesthetic agents in children are also addressed, along with the contrast agents that are typically required for imaging. With a global increase in worldwide travel the anticipation is that pediatricians will increasingly see unusual organisms presenting with CNS infection while dealing with the ever-present risk of drug resistance with inappropriately treated common or garden infections.