Bacterial meningitis is a serious problem in pediatric clinics and, therefore, needs urgent and empirical
chemotherapy. We investigated 1,116 cases of empirical
chemotherapy of patients aged older than 4 months from 1997 through 2008 by sending questionnaires. A single
antibiotic treatment was carried out in less than 30% of the cases throughout the years, whereas the combination of two
antibiotics had been practiced in more than 70% of the cases. The main
antibiotics used were
cephalosporins,
carbapenems, and
ampicillin. Combinatory use of
ampicillin and
cephalosporin was carried out in 74.7-82.7% of cases in 1997-2000, but sharply declined thereafter to 0-13.8% in 2004-2008. However, the combination of
carbapenem and
cephalosporin compensated for the decline, increasing from 3.8-6.6% in 1998-1999 to 79.5-89.9% in 2005-2008. The breakdown in the use of
cephalosporins,
carbapenems, and
ampicillin in two-
drug combinatory
therapy was as follows. (i) Use of
cefotaxime was 61.8-75.3% in 1997-2001, but decreased to nearly 50%, equivalent to the level of
ceftriaxone use in 2003-2008. (ii) Use of
ampicillin dropped from 74.7-92.3% in 1997-2000 to 4.6% in 2008, and this decreased level was compensated for by the use of
carbapenems. Overall, combinatory
chemotherapy of the
third-generation cephalosporins and
carbapenems seems to be practical. The discussion in this report includes the difference between Japan and the United States in the prevalence of the causative agents and the use of
antibiotics. These studies provide information on trends in the treatment of children's
meningitis in Japan and will be useful for the design of future empirical
chemotherapy.