Swami Sanjeev K, Banerjee Ritu
Division of Infectious Diseases, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE USA.
Springerplus. 2013 Dec;2(1):63. doi: 10.1186/2193-1801-2-63. Epub 2013 Feb 22.
Antibiograms created by aggregating hospital-wide susceptibility data from diverse patients can be misleading. To demonstrate the utility of age- and location-stratified antibiograms, we compared stratified antibiograms for three common bacterial pathogens, E. coli, S. aureus, and S. pneumoniae. We created stratified antibiograms based on patient age (<18 years, 18-64 years, >/=65 years), and inpatient or outpatient location using all 2009 E. coli and S. aureus, and all 2008-2009 S. pneumoniae isolates submitted to our clinical microbiology laboratory. We compared susceptibility rates among cumulative and stratified antibiograms using descriptive statistics.
For E. coli and S. aureus, the institution-wide antibiogram overestimated resistance in pediatic isolates and underestimated resistance in isolates from the elderly. For E. coli, pediatric isolates were less susceptible to ampicillin and ampicillin-sulbactam and more susceptible to gentamicin and ciprofloxacin compared to adult isolates (p < 0.05 for all), and isolates from patients >65 years were least susceptible to ciprofloxacin (71%). For S. aureus, susceptibility to oxacillin, clindamycin, and levofloxacin was highest among children and decreased with increasing age (p < .001 for all). For S. pneumoniae, pediatric isolates were less susceptible than adult isolates to all agents except penicillin (IV breakpoint). Within children there were significant differences in susceptibility of inpatient and outpatient isolates of E. coli but not of S. aureus or S. pneumoniae.
Stratified antibiograms reveal age - associated differences in susceptibility of E. coli, S. aureus, and S. pneumoniae that are obscured by hospital-wide antibiograms. Age-stratified antibiograms have potential to influence antibiotic selection.
通过汇总来自不同患者的全院药敏数据生成的抗菌谱可能会产生误导。为了证明按年龄和地点分层的抗菌谱的实用性，我们比较了三种常见细菌病原体（大肠杆菌、金黄色葡萄球菌和肺炎链球菌）的分层抗菌谱。我们根据患者年龄（<18岁、18 - 64岁、≥65岁）以及住院或门诊地点，使用2009年所有的大肠杆菌和金黄色葡萄球菌分离株，以及2008 - 2009年提交至我们临床微生物实验室的所有肺炎链球菌分离株，创建了分层抗菌谱。我们使用描述性统计方法比较了累积抗菌谱和分层抗菌谱之间的药敏率。
对于大肠杆菌和金黄色葡萄球菌，全院抗菌谱高估了儿科分离株的耐药性，低估了老年患者分离株的耐药性。对于大肠杆菌，与成人分离株相比，儿科分离株对氨苄西林和氨苄西林 - 舒巴坦的敏感性较低，对庆大霉素和环丙沙星的敏感性较高（所有p值均<0.05），65岁以上患者的分离株对环丙沙星的敏感性最低（71%）。对于金黄色葡萄球菌，儿童对苯唑西林、克林霉素和左氧氟沙星的敏感性最高，且随年龄增长而降低（所有p值均<0.001）。对于肺炎链球菌，除青霉素（静脉注射断点）外，儿科分离株对所有药物的敏感性均低于成人分离株。在儿童中，大肠杆菌住院和门诊分离株的药敏存在显著差异，但金黄色葡萄球菌和肺炎链球菌不存在这种差异。
分层抗菌谱揭示了大肠杆菌、金黄色葡萄球菌和肺炎链球菌药敏中与年龄相关的差异，而全院抗菌谱掩盖了这些差异。年龄分层的抗菌谱有可能影响抗生素的选择。
