Paisley J W, Lauer B A
Department of Pediatrics, Emanuel Children's Hospital, Portland, Oregon.
Clin Lab Med. 1994 Mar;14(1):17-30.
The clinical and laboratory issues important in pediatric blood cultures are similar to those in adult blood cultures with a few noteworthy exceptions. The collection of an uncontaminated specimen and an ample volume of blood is more difficult, especially in neonates. In addition, children often have previously received oral antibiotics or a broad-spectrum parenteral antibiotic. The relative frequencies of the pathogens causing bacteremia in children are different in important ways from in adults. Haemophilus influenzae b, although much less common than in the past, is still an important pediatric pathogen. Meningococcemia is relatively more common in children than in adults, and enterobacteriaceae and anaerobes are relatively less common. Group B streptococci, E. coli, coagulase-negative staphylococci, and Candida sp. are the principal pathogens in neonates. More changes in the distribution of blood-borne pathogens can be expected in the future with the introduction of new or more effective vaccines against the pneumococcus, meningococcus, and, possibly, group B streptococcus. In suspected community-acquired bacteremia in otherwise normal children, a single aerobic blood culture of adequate volume is sufficient. Sick neonates, hospitalized children with indwelling intravascular devices, and immunocompromised children may need multiple blood cultures, paired cultures from an indwelling vascular catheter and a peripheral vein, or use of special media. There is no single optimal system for pediatric blood cultures. The BACTEC systems have been adopted as a single system in many hospitals serving both children and adults because of the favorable results reported in children and the preference of using a single automated system. To maximize the detection of bacteremia and fungemia, some laboratories may wish to combine a BACTEC system with a second complementary system, such as the Isolator. Anaerobic, mycobacterial, and other special blood culture media should be reserved for selected patients.
儿科血培养中重要的临床和实验室问题与成人血培养相似，但有一些值得注意的例外情况。采集未受污染的标本和足量血液更困难，尤其是在新生儿中。此外，儿童之前常使用口服抗生素或广谱胃肠外抗生素。儿童中引起菌血症的病原体相对频率与成人有重要差异。b型流感嗜血杆菌虽然比过去少见得多，但仍是重要的儿科病原体。儿童中的脑膜炎球菌血症相对比成人更常见，而肠杆菌科细菌和厌氧菌相对少见。B族链球菌、大肠杆菌、凝固酶阴性葡萄球菌和念珠菌属是新生儿的主要病原体。随着针对肺炎球菌、脑膜炎球菌以及可能的B族链球菌的新疫苗或更有效疫苗的推出，预计未来血源性病原体的分布会有更多变化。在其他方面正常的疑似社区获得性菌血症儿童中，一次足量的需氧血培养就足够了。患病新生儿、有留置血管装置的住院儿童以及免疫功能低下的儿童可能需要多次血培养、从留置血管导管和外周静脉采集配对培养物或使用特殊培养基。儿科血培养没有单一的最佳系统。由于在儿童中报告的良好结果以及使用单一自动化系统的偏好，BACTEC系统已在许多为儿童和成人服务的医院中作为单一系统采用。为了最大限度地检测菌血症和真菌血症，一些实验室可能希望将BACTEC系统与第二个互补系统（如Isolator）结合使用。厌氧、分枝杆菌和其他特殊血培养培养基应保留给选定的患者。
