Article in Japanese

A case of meningitis caused by Streptococcus pneumoniae serotype 34 in one-year-old boy

Shoichi ISHIMARU^1）, Erika KURIHARA^1）, Yuho FUKANO^1）, Misato YOSHIDA^1）, Noriko TAKEUCHI^2）, Misako OHKUSU^2）, Emi SUGITA^1）, Naruhiko ISHIWADA^2）, Masaki KANAZAWA^1）, Masaru TERAI^1）

Since the introduction of the pneumococcal conjugate vaccine (PCV) as a routine immunization program in Japan, the incidence of pneumococcal meningitis in children has decreased significantly. However, cases of pneumococcal meningitis caused by non-vaccine serotypes (NVTs) have been reported. We experienced the case of a one-year-old boy with pneumococcal meningitis caused by NVTs. The patient had no underlying disease and had received PCV13 on four occasions. He was admitted to our hospital with vomiting and consciousness disorder. He exhibited signs of meningeal irritation, and treatment with ceftriaxone and vancomycin for suspected bacterial meningitis was initiated. Thereafter, Streptococcus pneumoniae was isolated in his blood and cerebrospinal fluid, and the susceptibility test revealed a receptiveness to penicillin. The clinical course was favorable, and he recovered without sequelae. Although there are few case reports of pneumococcal meningitis caused by serotype 34, most isolated strains are treatable with penicillin. On the other hand, there are reports that the nasopharyngeal carriage rate of serotype 34 is high. As a causative serotype of invasive pneumococcal diseases, evident after the introduction of PCV, it will need to be addressed with caution in the future.

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1）Department of pediatrics, Chiba kaihin municipal hospital
2）Department of infectious diseases, Medical mycology research center, Chiba university

Key words	Streptococcus pneumoniae, meningitis, serotype 34, non-vaccine serotypes
Received	December 16, 2023
Accepted	January 20, 2024

36 (2)：139─145,2024