Isolated pontine progressive multifocal leukoencephalopathy: unusual magnetic resonance imaging features

Brainstem progressive multifocal leukoencephalopathy

BACKGROUND AND PURPOSE

Progressive multifocal leukoencephalopathy (PML) is a severe infection caused by the polyomavirus JC that develops in the central nervous system (CNS) of immunosuppressed patients. The infection frequently starts in the brain hemispheres and can spread into other CNS regions such as the brainstem. Initial isolated PML brainstem lesions are exceptional. We aimed to describe the challenging diagnosis of PML with isolated brainstem lesions at the time of disease onset.

METHODS

We describe a case of PML starting with an isolated brainstem lesion and reviewed clinical, radiological, and biological features of all the reported cases of isolated brainstem PML.

RESULTS

Isolated brainstem PML at disease onset is extremely rare. In addition to our case, only nine PML cases presenting with strictly isolated radioanatomical brainstem location at the time of disease onset were retrieved through the literature. All patients share similar brain magnetic resonance imaging features, without contrast enhancement. Eight patients presented with initial clinical worsening, but full recovery occurred in three patients, partial recovery in two, and death in three. Even if prognosis is reserved because of the surrounding vital structures in the brainstem, clinical recovery may occur.

CONCLUSIONS

This case report and literature review emphasize that isolated brainstem lesion is an atypical presentation of PML at disease onset.

Progressive Multifocal Leukoencephalopathy: Recent Advances and a Neuro-Ophthalmological Review

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a severe often fatal opportunistic infection of the central nervous system caused by reactivation of a ubiquitous polyoma virus, JC virus. Although typically characterized by multifocal asymmetric subcortical white matter lesions, it may be monofocal and affect the cortical gray matter. Among the broad spectrum of clinical manifestations that occurs with PML, visual complaints are common.

EVIDENCE ACQUISITION

Combination of representative personally observed cases of PML and comprehensive review of case series of PML from 1958 through 2014.

RESULTS

Neuro-ophthalmic signs and symptoms were reported in approximately 20%-50% of patients with PML and can be the presenting manifestation in half of these. A majority of these presentations occur from damage to cerebral visual pathways resulting in visual field defects, cortical blindness, and other disorders of visual association. Given the decreased frequency of infratentorial and cerebellar involvement, ocular motility disorders are less common.

CONCLUSIONS

Visual complaints occur in patients with PML and are often the presenting sign. Awareness of this condition is helpful in avoiding unnecessary delays in the diagnosis of PML and management of the underlying condition. Recent guidelines have established criteria for diagnosis of PML in the high-risk patient population and strategies to mitigate the risk in these populations.

Head tremor and progressive multifocal leukoencephalopathy in AIDS patients: report of two cases

Progressive multifocal leukoencephalopathy (PML) is caused by replication of JC virus in oligodendrocytes of immunocompromised patients. Common manifestations are focal motor and sensory deficits, gait abnormalities, speech and language disturbances, cognitive disorders, headache, and visual impairment. Although the occurrence of movement disorders is rare in PML, bradykinesia, rigidity, dystonia, myoclonic jerks and myoclonic ataxia have been described. Head tremor associated with PML has not been previously reported. We report two cases of PML in whom head tremor was present.