Progressive multifocal leucoencephalopathy

The classic example of demyelination of the CNS is multiple sclerosis (MS), in which a chronic inflammatory lesion is characterised by a sharply demarcated plaque containing preserved axons denuded of myelin. Demyelination also occurs in infectious diseases such as progressive multifocal leucoencephalopathy and acute disseminated leucoencephalitis, but it is the disseminated focal form of MS that will be addressed in this review article. 

Nervous system Two patients treated with efalizumab for at least 3 years developed progressive cognitive and motor skills loss. JC virus was found in cerebral spinal fluid and despite plasma exchange with an associated rise in the expression of LFA-1 on peripheral T cells and restored activation of CD8+ T cells, the patients died of progressive multifocal leucoencephalopathy 2 and 6 months after disease onset. It was concluded that LFA-1 may be a crucial factor in homeostatic control of JC virus [134 ]. 

Nervous system Progressive multifocal leucoencephalopathy (PML) with immune reconstitution inflammatory syndrome (IRIS) may be a severe complication of natalizumab. Although natalizumab is often an effective treatment for patients with multiple sclerosis (MS), the mAb carries an associated risk of PML. A retrospective review of the first 40 natali-zumab-treated patients with MS revealed that 10 were also diagnosed with IRIS [174 ]. 

Hepatitis B virus reactivation Progressive multifocal leucoencephalopathy... 

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