Definition

Subacute sclerosing panencephalitis (SSPE) is a progressive, disabling, and deadly brain disorder related to measles (rubeola) infection.

The disease develops many years after the measles infection.

Alternative Names

SSPE; Subacute sclerosing leukoencephalitis; Dawson encephalitis; Measles - SSPE; Rubeola - SSPE

Causes

Normally, the measles virus does not cause brain damage. However, an abnormal immune response to measles or, possibly, certain mutant forms of the virus may cause severe illness and death. This response leads to brain inflammation (swelling and irritation) that may last for years.

SSPE has been reported in all parts of the world, but in western countries it is a rare disease.

Very few cases are seen in the United States since the nationwide measles vaccination program began. SSPE tends to occur several years after a person has measles, even though the person seems to have fully recovered from the illness. Males are more often affected than females. The disease generally occurs in children and adolescents.

Symptoms

Symptoms of SSPE occur in four general stages. With each stage, the symptoms are worse than the stage before:

• Stage I: There may be personality changes, mood swings, or depression. Fever and headache may also be present. This stage may last up to 6 months.
• Stage II: There may be uncontrolled movement problems including jerking and muscle spasms. Other symptoms that may occur in this stage are loss of vision, dementia, and seizures.
• Stage III: Jerking movements are replaced by writhing (twisting) movements and rigidity. Death may occur from complications.
• Stage IV: Areas of the brain that control breathing, heart rate, and blood pressure are damaged. This leads to coma and then death.

Exams and Tests

There may be a history of measles in an unvaccinated child. A physical examination may reveal:

• Damage to the optic nerve, which is responsible for sight
• Damage to the retina, the part of the eye that receives light
• Muscle twitching
• Poor performance on motor (movement) coordination tests

The following tests may be performed:

• Electroencephalogram (EEG)
• Brain MRI
• Serum antibody titer to look for signs of previous measles infection
• Spinal tap

Treatment

No cure for SSPE exists. Treatment is generally aimed at controlling symptoms. Certain antiviral medicines and medicines that boost the immune system may be tried to slow the progression of the disease.

Support Groups

The following resources can provide more information on SSPE:

• National Institute of Neurological Disorders and Stroke -- www.ninds.nih.gov/health-information/disorders/encephalitis?search-term=Subacute%20Sclerosing%20Panencephalitis
• National Organization for Rare Disorders -- rarediseases.org/rare-diseases/subacute-sclerosing-panencephalitis/

Outlook (Prognosis)

SSPE is always fatal. People with this disease die 1 to 3 years after diagnosis. Some people may survive longer.

When to Contact a Medical Professional

Contact your health care provider if your child has not completed their scheduled vaccines. The measles vaccine is included in the MMR vaccine.

Prevention

Immunization against measles is the only known prevention for SSPE. The measles vaccine has been highly effective in reducing the number of affected children.

Measles immunization should be done according to the recommended American Academy of Pediatrics and Centers for Disease Control schedule.

References

Gershon AA. Measles virus (rubeola). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 160.

Mason WH, Gans HA. Measles. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 273.