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The Journal of Pediatric Infectious Diseases and Immunology > Vol.33 No.1 contents > Abstract

Article in Japanese

A case of intrauterine infection of newborn considered to be caused by nontypeable Haemophilus influenzae

Mizuki AKIYOSHI1,3), Akiyoshi HORIE1), Naoko IMUTA4), Junichiro NISHI4), Akiyoshi NARIAI1,2)

This study reported a premature female infant with early onset neonatal nontypeable Haemophilus influenzae (NTHi) infection.
Four hours before delivery, the mother presented with spontaneous rupture of membranes followed by tachycardia, leukocytosis and elevated C-reactive protein (CRP). As fetal tachycardia on a cardiotocogram concerns chorioamunionitis (CAM), this infant was born at 33 weeks and 5 days of gestation by an emergency Caesarean section with asphyxia and a weight of 2,156 g.
Two days later, H. influenzae was isolated from cultures of placental tissue and diagnosed with CAM in the Caesarean section and umbilical cord, and ear and throat swabs of the newborn. Blood culture of the newborn was negative. Sepsis was diagnosed clinically. Assessment of drug susceptibility showed that the isolated strains were beta-lactamase non-producing ampicillin-resistant. Later, these strains were confirmed as NTHi and biotype III.
CAM also was confirmed in placental pathology findings, and NTHi was thought to have infected ascendingly through the birth canal.
NTHi strains are responsible for most H. influenzae infections in children in the post vaccine era. Therefore, continuous monitoring of them and their antimicrobial susceptibility, especially in neonates with early-onset neonatal infections is important in detecting changes in the epidemiology of H. influenzae infections in children in the post vaccine era.

1) Department of Pediatrics, Matue Red Cross Hospital
2) Department of Infectious Disease, Matue Red Cross Hospital
3) Department of Pediatrics, National Hospital Organization Hamada Medical Center
4) Department of Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences

Key words nontypeable Haemophilus influenzae, biotype, intrauterine infection, chorioamunionitis, early-onset neonatal infection
Received August 29, 2020
Accepted December 9, 2020

33 (1):35─40,2021