Division of Pediatric Neonatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
College of Medicine, Chang Gung University, Taoyuan, Taiwan.
BMC Infect Dis. 2019 Jun 19;19(1):538. doi: 10.1186/s12879-019-4177-y.
Group B Streptococcus (GBS) is an important pathogen that causes high mortality and morbidity in young infants. However, data on clinical manifestations between different GBS serotypes and correlation with molecular epidemiology are largely incomplete. The aim of this study was to determine the serotype distribution, antimicrobial resistance, clinical features and molecular characteristics of invasive GBS isolates recovered from Taiwanese infants.
From 2003 to 2017, 182 non-duplicate GBS isolates that caused invasive disease in infants less than one year of age underwent serotyping, multilocus sequence typing (MLST) and antibiotic susceptibility testing. The clinical features of these infants with GBS disease were also reviewed.
Of the 182 patients with invasive GBS disease, 41 (22.5%) were early-onset disease, 121 (66.5%) were late-onset disease and 20 (11.0%) were late late-onset disease (> 90 days of age). All these patients were treated with effective antibiotics on time. Among them, 51 (28.0%) had meningitis, 29 (16.0%) had neurological complications, 12 (6.6%) died during hospitalization, and 15 (8.8%) out of 170 patients who survived had long-term neurological sequelae at discharge. Serotype III GBS strains accounted for 64.8%, followed by serotype Ia (18.1%) and Ib (8.2%). MLST analysis revealed 11 different sequence types among the 182 isolates and ST-17 was the most dominant sequence type (56.6%). The correlation between serotype III and ST17 was evident, as ST17 accounted for 87.3% of all serotype III isolates. There was an obvious increasing trend of type III/ST-17 GBS that caused invasive disease in infants. All isolates were susceptible to penicillin, cefotaxime, and vancomycin, while 68.1 and 65.9% were resistant to erythromycin and clindamycin, respectively.
Despite timely and appropriate antibiotic treatment, a significant proportion of invasive GBS disease still inevitably causes adverse outcomes. Further study to explore preventive strategies and development of serotype-based vaccines will be necessary in the future.
B 群链球菌（GBS）是一种重要的病原体，可导致婴幼儿高死亡率和发病率。然而，不同 GBS 血清型的临床表现与分子流行病学之间的相关性数据在很大程度上并不完整。本研究旨在确定从台湾婴幼儿中分离出的侵袭性 GBS 分离株的血清型分布、抗微生物药物耐药性、临床特征和分子特征。
2003 年至 2017 年，对 182 例年龄小于 1 岁的婴儿侵袭性疾病的非重复 GBS 分离株进行了血清分型、多位点序列分型（MLST）和抗生素药敏试验。还回顾了这些患有 GBS 疾病的婴儿的临床特征。
182 例侵袭性 GBS 疾病患者中，41 例（22.5%）为早发型疾病，121 例（66.5%）为晚发型疾病，20 例（11.0%）为晚晚发型疾病（>90 天）。所有这些患者均及时接受了有效的抗生素治疗。其中，51 例（28.0%）有脑膜炎，29 例（16.0%）有神经并发症，12 例（6.6%）在住院期间死亡，170 例存活患者中有 15 例（8.8%）出院时有长期神经后遗症。血清型 III GBS 菌株占 64.8%，其次是血清型 Ia（18.1%）和 Ib（8.2%）。MLST 分析显示，182 株分离株中有 11 种不同的序列类型，ST-17 是最主要的序列类型（56.6%）。血清型 III 与 ST17 之间存在明显的相关性，因为 ST17 占所有血清型 III 分离株的 87.3%。引起婴儿侵袭性疾病的 III/ST-17 GBS 呈明显增加趋势。所有分离株对青霉素、头孢噻肟和万古霉素均敏感，而红霉素和克林霉素的耐药率分别为 68.1%和 65.9%。
尽管及时和适当的抗生素治疗，但侵袭性 GBS 疾病仍不可避免地导致相当大比例的不良结局。未来有必要进一步研究探索预防策略和基于血清型的疫苗开发。
