Article in Japanese

Association between pneumococcal bacteremia and febrile seizure in childhood: A retrospective observational study at a regional center, 2014-2024

Keiichi Nakata^1）, Kousaku Matsubara^1）, Moeka Kubo^1）, Kaya Kim^1）,Akiyoshi Naito^1）, Yu Kawasaki^1）, Chie Aota^1）, Kenichi Isome^1）, Masayuki Hori^1）, Aya Iwata^1）, Yoshimichi Yamaguchi^1）, Yoshimi Hiraumi^1）

We investigated the association between pneumococcal bacteremia （PB） and febrile seizures （FS） in children. This study included children aged 6-36 months who presented to a regional hospital during 2014-2024, corresponding to the 13-valent pneumococcal conjugate vaccine （PCV13） era. A total of 21 PB cases were identified, six （29%） of which were complicated by FS, with three （50%） classified as complex FS. All isolates were non-PCV13 serotypes, and 52% （11/21 strains） were PCV20 serotypes. Conversely, among children with FS, 627 underwent blood culture testing during the study period. Thus, the six PB infants with FS yielded to a detection rate of 1.0% among the 627 FS children with blood culture testing. The detection rate of PB did not differ between simple （0.9%, 3/321 cases） and complex （1.0%, 3/298 cases） FS. Leukocytosis was significantly more frequent in PB cases than in non-PB cases; however, its predictive value for PB was limited. To our knowledge, this is the first study to examine the relationship between PB and FS from both perspectives. This study demonstrated that during the PCV13 era, the frequency of FS among PB cases was relatively high, whereas the diagnostic rate of PB among FS cases was low. Our findings also suggest that the diagnostic rate of PB among FS cases may further decline following the introduction of PCV20.

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1）Department of Pediatrics, Kobe City Nishi-Kobe Medical Center

Key words	pneumococcal bacteremia, febrile seizure, complex febrile seizure, pneumococcal conjugate vaccine, invasive pneumococcal disease
Received	September 29, 2025
Accepted	November 28, 2025

37 (4)：299─309,2025