日本新生児成育医学会雑誌　第30巻　第1号　22～26頁（2018年）

日本新生児成育医学会雑誌　30(1)：22-26；2018　

受付日：平成28．12．16

受理日：平成29．05．08

Streptococcus dysgalactiae subsp. Equisimilis（SDSE）により早発型敗血症をきたした新生児の1 例

A case of Neonatal Early-Onset Sepsis Due to Streptococcus dysgalactiae subsp. Equisimilis

武蔵野赤十字病院　新生児科

Department of Neonatology, Japanese Red Cross Musashino Hospital

畠中大輔・草苅倫子・高橋秀弘・中村利彦・蒲原　孝

Daisuke HATANAKA，Michiko KUSAKARI，Hidehiro TAKAHASHI，Toshihiko NAKAMURA，Takashi KAMOHARA

Key Words：Streptococcus dysgalactiae subsp. Equisimilis（SDSE），Group G Streptococcus（GGS），neonatal sepsis, maternal transmission

　Streptococcus dysgalactiae subsp. Equisimilis（SDSE）による早発型敗血症をきたした正期産児の1 例を経験した。症例は在胎38 週5 日，出生体重3,102g，院外出生の男児。日齢1 に陥没呼吸と酸素飽和度の低下，血液検査でCRPの上昇を認めたため同日緊急搬送された。胸部X 線上，両側の気胸を合併していたが，抗菌薬の静注と酸素投与により後遺症なく回復した。入院時の血液培養および母体の腟培養からSDSE が検出されたため，母体からの垂直感染が強く示唆された。
　頻度は低いものの，新生児期SDSE 感染症はB 群溶連菌同様，致死的な経過をとる報告もあるため，新生児早発型敗血症の原因として留意すべきと考えられた。

　We present here an extremely rare case of neonatal early-onset sepsis due to Streptococcus dysgalactiae subsp. Equisimilis（ SDSE）in an outborn male infant delivered transvaginally at 38 weeks of gestation at a birthweight of 3,102g.
　On the infant’s 2 nd day of life, the patient experienced respiratory distress and serum CRP was elevated at 3.85 mg/dL. The infant was transferred emergently to our NICU. The infant was not doing well and was diagnosed with clinical sepsis. Intravenous antibiotic treatment was started immediately and the infant recovered shortly thereafter. A chest X-ray showed mild bilateral pneumothorax, which improved with supplemental oxygen administered for 4 days.
　Since SDSE was detected in both the infant’s blood and in a maternal vaginal smear, vertical transmission was strongly suspected.
　To the best of our knowledge, there has only been one report of neonatal sepsis due to SDSE in Japan. This will be the 2 nd case report. Neonatal SDSE infection is rare; however, there have been reports of fatal consequences, as well as group B streptococcal infection. SDSE should be considered one of the pathogens that cause neonatal early-onset sepsis.