Subacute Sclerosing Panencephalitis

Original Editor - Simran Shakeel

Top Contributors - Lucinda hampton, Simran Shakeel and Melissa Coetsee  

Introduction

Subacute sclerosing panencephalitis (SSPE) is a childhood and early adolescent neurological condition. It is caused by a measles virus that is persistently defective. Behavioral abnormalities, myoclonus, dementia, visual problems, and pyramidal and extrapyramidal symptoms are common in patients. The sickness progresses slowly and eventually results in death within 1-3 years.[1]

Pathology

The RNA virus that causes measles is a member of the marbillivirus subgroup of paramyxoviruses. Despite the considerable time between the acute infection and the onset of SSPE symptoms, there is evidence that measles virus infection of the brain occurs shortly after the acute infection and spreads throughout the brain.

In the early stages of SSPE, a brain biopsy reveals modest inflammation of the meninges and brain parenchyma, which includes cortical and subcortical grey matter as well as white matter. Neuronal degeneration, gliosis, astrocyte proliferation, perivascular cuffing, lymphocytic and plasma cell infiltration, and demyelination are all common findings. Extensive demyelination, which is common in individuals with SSPE, may be caused by viral infection of oligodendrocytes.

Gross examination of the brain in later phases may reveal modest to moderate cerebral cortical atrophy. A microscopic study reveals extensive neuron loss and cortical disorganisation. Pathological involvement spreads to the anterior regions of cerebral hemispheres, subcortical structures, brainstem, and spinal cord, with the parieto-occipital region of the brain being the most seriously afflicted. In the meninges and brain parenchyma, lymphocytes, plasma cells, and phagocytes form focal or diffuse perivascular infiltrates. Within neurons and oligodendrocytes, neurofibrillary tangles can be detected.It may be difficult to locate characteristic sites of inflammation and even inclusion bodies late in the course of the disease. Parenchymal necrosis and gliosis are prominent histological alterations.[1]

References

1. Garg RK Subacute sclerosing panencephalitis Postgraduate Medical Journal 2002;78:63-70.