Categories
Internal Medicine

Subacute sclerosing panencephalitis (SSPE)

Subacute sclerosing panencephalitis (SSPE) is a rare and chronic form of progressive brain inflammation caused by a persistent infection with measles virus (which can be a result of a mutation of the virus itself).

Subacute sclerosing panencephalitis (SSPE) is a rare and chronic form of progressive brain inflammation caused by a persistent infection with measles virus (which can be a result of a mutation of the virus itself).

  • No cure for SSPE exists and the condition is often fatal

Clinical features

History of primary measles infection usually before the age of 2 years, followed by several asymptomatic years (6–15 on average)

Gradual, progressive psychoneurological deterioration:

  • Personality change
  • Seizures
  • Myoclonus
  • Ataxia
  • Photosensitivity
  • Ocular abnormalities
  • Spasticity
  • Coma

Stage 1

  • Behaviour becomes abnormal and erratic:
    • Irritable and personality alterations, often accompanied by dementia
  • Lose control of movement, person develops myoclonic spasms/jerks

Stage 2

  • ↑ Intensity of spasms and the mental deterioration
  • Loss of the ability to walk
  • Speech impairment and increasingly deteriorated comprehension
  • Difficulty swallowing

Advanced stages

  • Steady decline in body function with increased intensity of stage 2 symptoms/signs
  • Blindness

Final stage

  • Mute patient, in a vegetative state, and/or comatose

Diagnosis

Clinical diagnosis:

  • Changes in personality
  • Gradual onset of mental deterioration
  • Myoclonia

Serology:

  • ↑ Anti-measles antibody (IgG) (serum & CSF)

Electroencephalogram (EEG):

  • Characteristic periodic activity (Rademecker complex)
  • Widespread cortical dysfunction

MRI:

bonthius1b
Subacute sclerosing panencephalitis. Figure 1. MRI scans of the brain at the time of presentation in the neurology clinic (A and B) and 3 months later (C and D). Panels A and C are T1-weighted images; B and D are T2-weighted images. The initial MRI scan (A and B) reveals a focal abnormality in the subcortical white matter of the left frontal lobe, consisting of a hypointense signal on the T1-weighted image (arrow in A) and a hyperintense signal on the T2-weighted image (arrow in B). In the follow-up scan, the focal abnormality in the left frontal lobe is less obvious than previously (arrow in D), but advanced and diffuse cortical atrophy is present, signified by the ventriculomegaly and markedly enlarged sulci (arrowheads in C). | Bonthius D, Stanek N, Grose C/ CDC – Bonthius D, Stanek N, Grose C (2000). “Subacute sclerosing panencephalitis, a measles complication, in an internationally adopted child”. Emerg Infect Dis 6 (4): 377-81. PMID 10905971, Public Domain, https://commons.wikimedia.org/w/index.php?curid=3584836

Tissue biopsy:

  • White matter of both the hemispheres and brainstem affected, as well as the cerebral cortex
  • Eosinophilic inclusion bodies are present in the nuclei of neurons (gray matter) and oligodendrocytes (white matter)

Differential diagnosis:

  • Acute disseminated encephalomyelitis

Management

Stage 1:

  • Oral inosine pranobex (oral isoprinosine) + intrathecal/intraventricular interferon alpha
  • Oral inosine pranobex (oral isoprinosine) + interferon beta
  • Intrathecal interferon alpha + IV ribavirin

Stage 2 or beyond

Incurable

Leave a Reply