[Post-vaccinal hemi-convulsion hemiplegia syndrome].

An 18-month-old infant developed hemiseizure-hemiplegia syndrome following a booster dose of vaccine against diphtheria, pertussis, tetanus, and poliomyelitis. Clinical, CT scan, and electroencephalographic findings during the two-and-a-half-year follow-up are described. The timing of events and data from the literature suggest that hemiseizure-hemiplegia syndrome is related to post-immunization hyperthermia rather than to direct neurologic toxicity of the vaccine.