A case of acute encephalopathy following exanthema subitum with symmetrical hypodensity of bilateral basal ganglia on CT

A 7-month-old boy was sent to our hospital because of frequent convulsions and a semicoma which occurred 3 days after the onset of exanthema subitum. There were no particular hematological and biochemical findings except that the protein of cerebro-spinal fluid increased. There was a symmetrical hypodensity of bilateral corpora striata on the CT and a diffuse slowing of the EEG was found. Consciousness was regained 10 days after admission and transient intention tremor was then found. A month after admission, the latency of the 1st wave of ABR transiently became prolonged, but the interpeak latency of the I-V has been continuously within normal limits. Recordings of SSEP were normal. After 2 years' follow-up, we found that he had developed normally and that his EEG recordings had become almost normal, but hypodensity of the bilateral corpora striata on CT still existed. This case was the first report of infantile bilateral striatal necrosis associated with exanthema subitum. (author)