Progressive multifocal leucoencephalopathy

Disease course and outcome of 15 monocentrically treated natalizumab-associated progressive multifocal leukoencephalopathy patients

OBJECTIVE

Although the prognosis of natalizumab-associated progressive multifocal leukoencephalopathy (PML) seems to be better than HIV-associated PML, little is known about the long-term functional outcome in multiple sclerosis (MS) patients and the subsequent return of MS disease activity. We evaluated retrospectively 15 patients with natalizumab-associated PML treated at our centre.

PATIENTS AND METHODS

Fifteen MS-PML patients (nine women, six men) were referred to us from adjacent local centres. The patients had a median natalizumab exposure of 34 months at PML diagnosis. They received standardised treatment as described in previous work. Expanded Disability Status Scale (EDSS) and Karnofsky score in the year pre-PML, at PML-diagnosis (pre-immune reconstitution inflammatory syndrome (IRIS)) and post-PML were determined in 3-6 monthly intervals.

RESULTS

The median follow-up of these 15 patients was 21.5 months. None of the 15 patients died. Three patients had a Karnofsky score of 80 or higher, nine patients between 50-70 and three patients of 40 or lower at latest examination. Eight of the 15 patients developed seizures during acute PML phase. Fifty percent of those patients were not seizure-free one year post PML, despite continuation of antiepileptic treatment. The median EDSS in the year pre-PML was 2.5, 4.5 at PML diagnosis, 6.5 post-IRIS and 5.5 at latest examination. CSF became virus-free in eight of the 15 patients after a median time of 4.5 months. In nine patients, disease reappeared after a median time of seven months from PML diagnosis.

CONCLUSIONS

Although the clinical outcome of natalizumab-treated PML patients is much better than in patients with HIV-associated PML, this may be further improved by treatment at reference centres using standardised therapy regimens and transient intensive care if needed. Systematic studies of appropriate MS immunotherapies after PML are critically needed.

JC virus leukoencephalopathy complicating Wegener's granulomatosis

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the brain caused by the JC virus. It occurs in association with immunodepression due, for instance, to a hematological malignancy, HIV infection, or immunosuppressive therapy for an organ transplant or systemic disease. We describe the fourth reported case of PML in a patient receiving immunosuppressants for Wegener's granulomatosis. A 71-year-old woman receiving azathioprine and glucocorticoid therapy experienced onset of right-sided hemiplegia within a few days, became comatose, and died within a few days. MRI of the brain showed a subcortical lesion in the left parietal lobe generating low signal on T1 images and high signal on T2 images. The initial diagnosis was cerebral vasculitis. However, the postmortem examination showed PML. The diagnosis of PML rests on JC virus detection in the cerebrospinal fluid by PCR assay and on demonstration in a brain biopsy of the typical histological pattern with presence of the JC virus within the demyelinated lesions. No specific or effective treatments are available. Immunosuppressant drugs should be discontinued if possible.

Progressive multifocal leukoencephalopathy presenting with an isolated focal movement disorder

Progressive multifocal leukoencephalopathy (PML) is a rare but fatal papovavirus infection of the central nervous system predominantly affecting immunocompromised patients. Although the basal ganglia circuitry may be involved in the pathology of PML, movement disorders are exceedingly rare as presenting symptoms and have not been described as isolated features in such patients. We report a previously healthy, immunocompetent 24-year-old woman with histologically proven PML who presented with a focal movement disorder of the left arm as an isolated symptom for many months before diagnosis.