[A study of bacterial meningitis in Hokkaido between 1999 and 2003].

We evaluated 83 children with bacterial meningitis in 67 of 81 insitutions in Hokkaido, Japan between 1999 and 2003 by questionnaire. The incidence of bacterial meningitis in children aged < 5 years and 5 < or =, < 10 years was 6.3 and 0.7 cases per 100, 000 children/year. The incidences of meningitis due to Haemophilus influenzae, Streptococcus pneumoniae, and Streptococcus agalactiae in children aged < 5 years were 3.7, 1.4 and 0.8. Median age was 13 months ranging from 0 day to 9 years. Seventy-four (89.1%) of the total were less than 5 years old with 39 (47.0%) less than 1 year old. Major causative organisms were H. influenzae in 51 patients, S. pneumoniae in 18, S. agalactiae in 9 and E. coli in 3. Four deaths occurred, giving an overall case mortality rate of 4.8%. Sequelae were seen at discharge in 25.3%, predominantly epilepsy, hearing loss, and developmental delay of varying severity. The frequency of poor prognosis was 55.6% for patients with meningitis due to S. pneumoniae compared with 21.6% for H. influenzae and 22.2% for S. agalactiae.