Clin Lab. 2024 Feb 1;70(2). doi: 10.7754/Clin.Lab.2023.230341.
Bloodstream infections (BSI) represent a common cause of sepsis and mortality in children. Blood culture (BC) is the gold standard for diagnosis of BSI. The low sensitivity of BC in the pediatric population is usually due to the small volume of blood used for inoculation and to the antibiotics used before sampling. Here, we explore the ways to effectively reduce antibiotic activity to maximize the chances of pathogen recovery, and to enhance the growth of microorganisms in lower blood volume and bacterial counts.
The recovery of common pathogens causing blood stream infections was analyzed after exposure to cefo-perazone/sulbactam, vancomycin, and caspofung by using resin-containing or not BacT/Alert PF Plus and BD FX400 peds plus pediatric bottles. The microbial growth in the resin-containing bottles was assessed using 0.5 colony-forming units (CFU) bacterial inoculum to mimic the bacteremia/fungemia condition. The usefulness of a diagnosis to confirm or exclude BSI was evaluated by lower than recommended blood culture sampling (102 CFU/mL, 0.3 mL).
Staphylococcus aureus (S. aureus), and Candida glabrata (C. glabrata) were recovered from 100% of two types of resin-containing bottles in the presence of a sufficient antibiotic dose, while Escherichia coli (E. coli) was not restored to 100% in BD FX400 peds plus pediatric bottles. The shorter TTD for S. aureus, C. glabrata, and E. coli were observed in antibiotic-containing BacT/Alert PF Plus bottles. Both the PF Plus and BD resin test bottles showed consistently good TTD performances to Gram-negative, Gram-positive, and yeast species in low inoculum levels, with the exception of S. aureus. The lower volume of blood inoculated into culture bottles hardly affected the growth of most bacteria, but optimized PF Plus resin-bottles accelerated the detection of infectious agents, especially S. aureus, Streptococcus pneumoniae, and C. glabrata.
It is possible to enhance recovery from antibiotic-containing pediatric bottles and shorten TTD for the identification of pathogens by using the BacT/Alert blood culture system combination with new resin-containing media.
血流感染（BSI）是儿童败血症和死亡的常见原因。血培养（BC）是诊断 BSI 的金标准。儿科人群中 BC 的灵敏度通常较低，这是由于接种时使用的血量较小以及采样前使用的抗生素。在这里，我们探索了有效降低抗生素活性的方法，以最大限度地提高病原体恢复的机会，并增强低血量和细菌计数下微生物的生长。
使用含有或不含有树脂的 BacT/Alert PF Plus 和 BD FX400 peds plus 儿科瓶，分析头孢哌酮/舒巴坦、万古霉素和卡泊芬净暴露后常见引起血流感染的病原体的恢复情况。使用 0.5 个菌落形成单位（CFU）细菌接种物评估含有树脂瓶中的微生物生长，以模拟菌血症/真菌血症情况。通过低于推荐的血培养采样（102 CFU/mL，0.3 mL）评估诊断对确认或排除 BSI 的有用性。
在足够的抗生素剂量存在下，100%从两种类型的含有树脂的瓶中回收金黄色葡萄球菌（S. aureus）和光滑念珠菌（C. glabrata），而大肠埃希菌（E. coli）在 BD FX400 peds plus 儿科瓶中未恢复到 100%。在含有抗生素的 BacT/Alert PF Plus 瓶中观察到 S. aureus、C. glabrata 和 E. coli 的 TTD 更短。PF Plus 和 BD 树脂测试瓶在低接种量下对革兰氏阴性、革兰氏阳性和酵母属均表现出一致良好的 TTD 性能，除了 S. aureus 之外。将更少的血液接种到培养瓶中几乎不会影响大多数细菌的生长，但优化的 PF Plus 树脂瓶加速了感染因子的检测，特别是 S. aureus、肺炎链球菌和 C. glabrata。
通过使用 BacT/Alert 血培养系统与新的含树脂介质相结合，有可能增强含抗生素儿科瓶中的恢复并缩短 TTD 以鉴定病原体。
