The microbiological characteristics of group B streptococcus at Japanese pediatric hospitals

Abstract

Mihoko Furuichi,1 Kaoru Goto,2 Nobuyuki Tetsuka,3 Katsushi Ishida,4 Isao Miyairi,3 Yoshiaki Cho,5 Masashi Kasai,6 Yukiya Kurahashi,7 Hideki Akeda,7 Yuho Horikoshi1 1Division of Infectious Diseases, Department of Pediatrics, 2Division of Microbiology, Department of Clinical Laboratory, Tokyo Metropolitan Children’s Medical Center, 3Division of Infectious Diseases, Department of Pediatrics, 4Division of Microbiology, Department of Clinical Laboratory, National Center for Child Health and Development, Tokyo, 5Department of Pediatrics, 6Division of Pediatric Critical Care Medicine and Infectious Disease, Nagano Children’s Hospital, Nagano, 7Department of General Pediatrics, Okinawa Prefectural Nanbu Medical Center & Children’s Medical Center, Okinawa, Japan Abstract: Group B streptococcus (GBS) is an important cause of serious bacterial infections (SBIs) in infants. Non-penicillin-susceptible GBS strains have been reported among adults, but little is known among children. We collected GBS isolates from 4 children’s hospitals in Japan, and performed serotyping of GBS strains and reviewed penicillin minimum inhibitory concentrations of GBS strains from both sterile and non-sterile sites. Our examination revealed 235 isolates including 41 isolates from SBIs and 194 isolates from colonization. Nine cases of GBS SBIs (21.9%) were early-onset, 19 (46.3%) were late-onset, and 13 (31.7%) were ultra-late-onset. Non-penicillin-susceptible GBS strains were not detected among either isolates. Serotypes Ia, Ib, and III were predominant among SBIs. In conclusion, at this time, we have no non-penicillin-susceptible GBS strains in Japanese children. Penicillin susceptibility should continue to be monitored carefully in each geographic area. Keywords: GBS, serotypes, penicillin, MIC, children

Keywords

• GBS
• Serotypes
• Penicillin
• MIC
• Children