Subacute Sclerosing Panencephalitis
Original Editor - Simran Shakeel
Introduction[edit | edit source]
Subacute sclerosing panencephalitis (SSPE) is a slowly progressive brain disorder caused by mutant measles virus (also known as Dawson disease). SSPE typically affects children and adolescents several years after initial infection with the measles.and its incidence is proportional to that of measles. High-income countries have experienced solid declines in SSPE incidence following universal vaccination against measles.
- 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.
Image SSPE - MRI scans of the brain at the time of presentation in the neurology clinic (A and B) and 3 months later (C and D). The initial MRI scan (A and B) reveals a focal abnormality in the subcortical white matter of the left frontal lobe. In the followup scan, advanced and diffuse cortical atrophy is present, signified by the ventriculomegaly and markedly enlarged sulci.
Epidemiology[edit | edit source]
1 in 100,000 people infected with measles develop SSPE, with a latency of typically a decade (range 4-23 years). Developed nations have benefited from widespread vaccination, as SSPE is very rare in these countries.
Etiology[edit | edit source]
SSPE is caused by the measles virus, a single-stranded RNA virus (of the paramyxoviridae family). It is highly contagious, with measles being transmitted to 12 to 18 persons from one infected individual. Transmission occurs through aerosols from person to person. Many complications can occur acutely and chronically, for example the neurological complications seen in SSPE.
Clinical Presentation[edit | edit source]
- The early symptoms are usually poor school performance, forgetfulness, temper outbursts, easily distracteded, poor sleep, and hallucinations.
- Unexpected muscular jerks of the arms, head, or body may occur, and finally seizures may occur, together with abnormal uncontrollable muscle movements. Intellect, eyesight and speech continue to deteriorate.
- Later, the muscles become increasingly rigid, and swallowing becomes difficult (dysphagia), potentially causing person to choke on their saliva, resulting in pneumonia.
Diagnosis[edit | edit source]
A suspicion is raised of SSPE in young people who have had the measles virus and who present later with mental deterioration and muscle jerks.
- The diagnosis may be confirmed by examination of cerebrospinal fluid, a blood test that reveals high levels of antibody to the measles virus, by an abnormal electroencephalogram (EEG), and by MRI or CT that shows brain abnormalities.
- A biopsy of the brain may need to be done if the tests cannot reveal a cause.
Treatment and Prognosis[edit | edit source]
Unfortunately nothing can be done to stop the progression of subacute sclerosing panencephalitis.
- Treatments that attempt to prolong and improve the quality of life can have some side effects/complications.
- The mortality rate is exceptionally high in the case of SSPE, about 95%, while the remaining cases undergo spontaneous remission.
References[edit | edit source]
- Garg RK, Mahadevan A, Malhotra HS, Rizvi I, Kumar N, Uniyal R. Subacute sclerosing panencephalitis. Reviews in Medical Virology. 2019 Sep;29(5):e2058. Available:https://onlinelibrary.wiley.com/doi/10.1002/rmv.2058 (accessed 30.9.2022)
- Radiopedia SSPE Available: https://radiopaedia.org/articles/subacute-sclerosing-panencephalitis-1(accessed 30.9.2022)
- Rocke Z, Belyayeva M. Subacute Sclerosing Panencephalitis. Available:https://www.ncbi.nlm.nih.gov/books/NBK560673/ (accessed 30.9.2022)
- MSD Manual Subacute Sclerosing Panencephalitis (SSPE) Available: https://www.msdmanuals.com/en-au/home/children-s-health-issues/viral-infections-in-infants-and-children/subacute-sclerosing-panencephalitis-sspe(accessed 30.9.2022)
- NIH SSPE Available:https://www.ninds.nih.gov/myoclonus-fact-sheet (accessed 30.9.2022)