Retinitis and dementia in a pregnant girl: an unusual case.

A 14-year-old pregnant Caucasian girl presented with a 1-week history of dementia. She had presented 1 year prior with acute unilateral visual impairment and was noted to have macular degeneration of presumed infective aetiology. This evolved to a pigmentary macular lesion. During the course of the current presentation she developed myoclonic jerks. An electroencephalogram revealed periodic spike and slow wave complexes at 1-2 second intervals. Blood and cerebrospinal fluid examination showed raised anti-measles IgG antibody titres. Intrathecal synthesis of anti-measles virus antibody was demonstrated unequivocally and a diagnosis of subacute sclerosing panencephalitis was made. A healthy male infant was delivered by elective caesarean section at 33 weeks' gestation. She continued to deteriorate clinically despite treatment with intraventricular alpha-interferon. She had not had primary immunization against measles.