Safdar A, Rodriguez G H, Balakrishnan M, Tarrand J J, Rolston K V I
Department of Infectious Diseases, Infection Control, and Employee Health, Unit 402, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
Eur J Clin Microbiol Infect Dis. 2006 Aug;25(8):522-6. doi: 10.1007/s10096-006-0173-4.
The present study was conducted to determine trends in the quantitative bacterial load patterns of bacterial bloodstream infections (BSI) caused by various bacteria in patients receiving care at a comprehensive cancer center. Bacterial loads of all consecutive quantitative blood cultures performed during 1998 and 2004 were graded quantitatively. Gram-positive bacteria (GPB) were responsible for the majority of BSI episodes in both years studied: 740 of 1,055 (73%) in 1998 and 820 of 1,025 (82%) in 2004. Compared with GPB infections, a significant proportion of infections caused by Gram-negative bacteria was associated with a high bacterial load (HBL) (11 vs 28% in 1998 and 10 vs 30% in 2004; p<0.001). In 2004, BSI episodes due to non-Pseudomonas non-fermentative GNB (Stenotrophomonas maltophilia and Acinetobacter spp) were significantly associated with a HBL compared to BSI due to Pseudomonas aeruginosa (47 vs 23%; p<0.05); this was not the case in 1998. Conversely, the HBLs commonly associated with BSI due to Staphylococcus aureus (50%) and Streptococcus spp (35%) versus coagulase-negative staphylococci (13%; p<0.0001) during 1998 were not noted during 2004 (22% Staphylococcus aureus, 20% Streptococcus spp, 21% coagulase-negative staphylococci; p>0.5). The spectrum of BSI continues to change and its prognostic implications in cancer patients needs further study.
本研究旨在确定在一家综合癌症中心接受治疗的患者中，由各种细菌引起的细菌性血流感染（BSI）的定量细菌载量模式的趋势。对1998年至2004年期间进行的所有连续定量血培养的细菌载量进行了定量分级。在这两年的研究中，革兰氏阳性菌（GPB）导致了大多数BSI发作：1998年1055例中的740例（73%），2004年1025例中的820例（82%）。与GPB感染相比，革兰氏阴性菌引起的感染中有很大一部分与高细菌载量（HBL）相关（1998年为11%对28%，2004年为10%对30%；p<0.001）。2004年，与铜绿假单胞菌引起的BSI相比，非假单胞菌非发酵革兰氏阴性菌（嗜麦芽窄食单胞菌和不动杆菌属）引起的BSI发作与HBL显著相关（47%对23%；p<0.05）；1998年情况并非如此。相反，1998年期间金黄色葡萄球菌（50%）和链球菌属（35%）引起的BSI与凝固酶阴性葡萄球菌（13%；p<0.0001）相关的HBL在2004年未观察到（金黄色葡萄球菌22%，链球菌属20%，凝固酶阴性葡萄球菌21%；p>0.5）。BSI的谱图持续变化，其对癌症患者的预后影响需要进一步研究。
