Once SSPE develops, it moves through progressive stages, starting with mood swings, personality changes, depression, lethargy, and possibly fever and headache. This first stage can last up to six months. Then stage two involves jerking movement, spasms, loss of vision, dementia, and seizures. The third stage sees the jerking turn to writhing and rigidity. In the last stage, autonomic failure sets in—heart rate, blood pressure, and breathing become unregulated. Then comes coma and death. About 95 percent of SSPE cases are fatal.
Tragic ending
In the boy’s case, his parents don’t know when he was infected with measles. When doctors saw him, his parents recalled that in the prior six months, he had started having jerky movements, falls, and progressive cognitive decline. Before that, he had been healthy at birth and had been hitting all of his developmental milestones.
In some ways, his decline was an unmistakable case of SSPE. Imaging showed lesions in his brain. He had elevated anti-measles antibodies in his cerebrospinal fluid. An electroencephalography (EEG) showed brain waves consistent with SSPE. Then, of course, there were the jerking motions and the cognitive decline.
What stood out, though, was his rolling and swirling eyes. Vision problems are not uncommon with SSPE—sometimes the condition damages the retina and/or optic nerve. Some patients develop complete vision loss. But, in the boy’s case, he developed rapid, repetitive, erratic, multidirectional eye movements, a condition called opsoclonus. Doctors often see it in brain cancer patients, but brain inflammation from some infections can also cause the movements. Experts hypothesize that the root cause is a loss of specialized neurons involved in coordinated movement, namely Purkinje cells and omnipause cells.
The boy’s neurologists believe this is the first time opsoclonus associated with SSPE has been caught on video. They treated the boy with an antiviral drug and drugs to reduce convulsions, but his condition continued to worsen.