RESUMO
INTRODUCTION: Subacute sclerosing panencephalitis is a disease affecting the central nervous system that is produced by persistent infection by a defective measles virus. This disease is very infrequent and its incidence has gone down even further in western countries since the introduction of generalised measles vaccinations. Onset of the disease is usually during infancy or adolescence. Reports of cases beginning during adulthood are scarce. CASE REPORT: We describe the case of a 30-year-old female with a slowly progressive subacute clinical picture consisting in behavioural disorders, with defrontalisation, cortico-subcortical cognitive impairment, long tract signs and visual disorders, which led the patient into a vegetative state. Four years after the onset of symptoms the patient died. The different electroencephalogram recordings performed did not show any periodic activity and magnetic resonance imaging of the head revealed cerebral atrophy with hyperintense lesions in T2 sequences in white matter. The histological study of the brain showed a chronic inflammatory infiltration with neuronal loss and demyelination, as well as intranuclear inclusions and neurofibrillary degeneration. CONCLUSIONS: The appearance of subacute sclerosing panencephalitis in adulthood is exceptional. Diagnosis requires a high degree of clinical suspicion, above all in the absence of typical symptoms, such as myoclonias or periodic complexes in EEG recordings.