We studied the incidence and prognosis of acute neurologic complications in 281 children under 13 years of age with a diagnosis of acute bacterial meningitis. All the patients were examined daily by the same group of neurologists, using a standardized neurological examination. Patients with signs of encephalic lesions, unsatisfactory response to antibiotics or decreased level of consciousness were submitted to brain computer tomography. The overall lethality rate was 20.3% and cases whose causative agent was identified presented a higher lethality rate (23.7%) than those in which the agent was not found. The most important neurological abnormalities were meningeal signs (88.3%) followed by decreased consciousness (47.7%), irritability (35.2%), seizures (22.4%), fontanel bulging (20.6%) and cranial nerve palsy (14.2%). Seizures, cranial nerve palsy and the absence of meningeal signs were related to higher rates of lethality. Diminished consciousness, seizures, subdural effusion, abscess and hydrocephalus were the most important complications, respectively. We can conclude that acute bacterial meningitis continues to be an important health problem in developing countries and that public health measures will be necessary to minimize the impact of sequelae and reduce the mortality rate in children with that pathology.