Trend of bacterial meningitis in children over a 14 year period (1981 through 1994) in Japan--an analysis based on studies in 27 institutions]

We observed 266 children with purulent meningitis in 27 institutions in Japan during the 14 years from 1981 on dividing these years into 3 periods, 1981-1985, 1986-1990 and 1991-1994, and studied the trend of causative organisms identified in 254 among the 266 patients. Their ages were less than 3 months after birth in 50 children and 3 months or older in 216: there were 141 boys and 125 girls. The causative organisms were H. influenzae in 134 patients and S. pneumoniae in 50, most of them being aged 3 months or older. Next to the above bacteria ranked S. agalactiae in 29 and E. coli in 12, many of the patients were aged less than 3 months. Staphylococcus spp. was found in 7 patients and about 70% of them were aged 3 months or older. L. monocytogenes was found in 4 patients and N. meningitidis in 3 and they were aged 3 months or older in both patient groups. S. pyogenes, Enterococcus spp., Peptostreptococcus spp., P. Mirabilis and Enterobacter spp. were detected each in 1 patient. The causative organism was unknown in 21 patients and there was no double infection. H. influenzae were detected in 18 patients in 1981-1985 period (36.7%), in 56 in 1986-1990 (54.9%) and in 60 in 1991-1994 (63.8%) showing an increasing tendency, but S. pneumoniae exhibited neither an increasing nor decreasing tendency. There was a decreasing tendency with S. agalactiae and E. coli, but the details were not clear because there were few patients aged less than 3 months. Although the period of coexistence of 4 main bacterial species was not made clear in this study. Listeria is considered to develop mainly in the early childhood, and we believe that the conventional way of using a cephem preparation and ampicillin combined for patients under 6 years need not be altered. However, panipenem (phonetic) is likely to be effective for insensible S. pneumoniae for the time being.