Symptoms:

• Bizarre behavior
• Dementia (loss of cognitive (thought), emotional, and social abilities)
• Coma
• Gradual behavioral changes
• Myoclonic jerking (quick muscle jerking or spasms)
• School problems
• Seizures
• Unsteady gait
• Very tense muscles or muscles that lack tone, with weakness in both legs

Signs 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