Department of Pediatrics, Division of Infectious Diseases, MHS Johns Hopkins Medical Institutions, 200 N Wolfe St, Baltimore, MD 21287, USA.
Clin Infect Dis. 2013 Sep;57(6):781-8. doi: 10.1093/cid/cit395. Epub 2013 Jun 11.
AmpC β-lactamase-producing organisms are associated with significant morbidity and mortality. Induction of resistance to third-generation cephalosporins after exposure to these agents complicates treatment options and carbapenems are considered optimal therapy. The role of cefepime, however, remains unclear. Our objective was to compare clinical outcomes for patients receiving cefepime compared with meropenem for invasive infections caused by organisms expressing AmpC β-lactamases.
Hospitalized patients with blood, bronchoalveolar lavage, or intra-abdominal fluid cultures growing Enterobacter spp, Serratia spp, or Citrobacter spp were evaluated using the cefotetan-boronic acid disk test and the cefotetan-cloxacillin Etest to identify organisms with AmpC β-lactamase production from February 2010 to January 2011. In patients with organisms hyperproducing AmpC β-lactamases (positive by both methods), clinical outcomes for patients receiving cefepime or meropenem therapy were compared. To minimize the possibility of treatment selection bias, 1:1 nearest neighbor propensity score matching was performed prior to regression analysis.
Of 399 patients meeting eligibility criteria, 96 (24%) had confirmed infections with AmpC β-lactamase-producing organisms. Propensity score matching of patients infected with AmpC β-lactamase-positive organisms treated with cefepime or meropenem yielded 32 well-balanced patient pairs with no difference in 30-day mortality (odds ratio, 0.63; 95% confidence interval [CI], .23-2.11; P = .36) or length of hospital stay after infection (relative risk, 0.96; 95% CI, .79-1.26; P = .56) between the 2 groups.
Cefepime may be a reasonable option for the treatment of invasive infections due to AmpC β-lactamase-producing organisms, particularly when adequate source control is achieved.
产 AmpCβ-内酰胺酶的生物体与显著的发病率和死亡率相关。暴露于这些药物后对第三代头孢菌素产生耐药性会使治疗选择复杂化，而碳青霉烯类被认为是最佳治疗药物。然而，头孢吡肟的作用仍不清楚。我们的目的是比较接受头孢吡肟与美罗培南治疗由表达 AmpCβ-内酰胺酶的生物体引起的侵袭性感染的患者的临床结局。
使用头孢替坦-硼酸盘试验和头孢替坦-氯唑西林 E 试验，对 2010 年 2 月至 2011 年 1 月期间血、支气管肺泡灌洗液或腹腔液培养生长的肠杆菌属、沙雷氏菌属或柠檬酸杆菌属的住院患者进行评估，以鉴定产 AmpCβ-内酰胺酶的生物体。对于 AmpCβ-内酰胺酶过度产生的生物体（两种方法均为阳性）的患者，比较接受头孢吡肟或美罗培南治疗的患者的临床结局。为了最大程度地减少治疗选择偏倚的可能性，在进行回归分析之前，对 1:1 最近邻倾向评分匹配进行了处理。
符合入选标准的 399 例患者中，96 例（24%）确认为 AmpCβ-内酰胺酶阳性生物体感染。对接受头孢吡肟或美罗培南治疗的 AmpCβ-内酰胺酶阳性感染患者进行倾向评分匹配，得到 32 对匹配良好的患者，两组 30 天死亡率（比值比，0.63；95%置信区间 [CI]，.23-2.11；P =.36）或感染后住院时间（相对风险，0.96；95% CI，.79-1.26；P =.56）无差异。
当获得充分的病因控制时，头孢吡肟可能是治疗由 AmpCβ-内酰胺酶阳性生物体引起的侵袭性感染的合理选择。
