Cattaneo C, Quaresmini G, Casari S, Capucci M A, Micheletti M, Borlenghi E, Signorini L, Re A, Carosi G, Rossi G
U. O. Ematologia, Spedali Civili, Brescia, Italy.
J Antimicrob Chemother. 2008 Mar;61(3):721-8. doi: 10.1093/jac/dkm514. Epub 2008 Jan 24.
Regular monitoring of bacterial epidemiology allows evaluation of antibacterial strategies adopted. The aim of this study was to disclose evolving trends in the epidemiology of infections and emerging antibiotic resistance in unselected inpatients with haematological cancers.
Febrile/infectious episodes occurring in 823 patients consecutively admitted to a single institution during a 16 month period were analysed. Levofloxacin prophylaxis was used in patients with >7 days expected neutropenia.
Fever developed in 364 patients (44.2%) and an infection was documented in 187 (22.7%), either clinically (6.1%) or microbiologically (16.6%). Levofloxacin prophylaxis, used in 39.4% of cases, caused a reduction in febrile episodes only among neutropenic patients and no difference in the frequency of documented infections. Among 164 pathogens isolated, gram-negative (49.4%) outweighed gram-positive bacteria (40.9%), Escherichia coli being most frequent (23.2%). Fluoroquinolone resistance and methicillin resistance were the most frequent types of antibiotic resistance, occurring in 56.1% of bacterial isolates and in 66.7% of staphylococci, respectively. Fluoroquinolone-resistant E. coli accounted for 20.1% of all isolates and for 86.8% of E. coli. Multivariate analysis of risk factors for fluoroquinolone resistance identified prophylaxis (P < 0.001) and neutropenia >7 days (P = 0.02) as independent. Methicillin resistance was independently associated with prophylaxis (P = 0.041) and central venous catheters (P = 0.036). Infections by fluoroquinolone-resistant strains did not show a worse outcome.
A shift towards gram-negative bacteria has been occurring in recent years in the bacterial epidemiology of haematological patients. Fluoroquinolone resistance is emerging as a major type of antibacterial resistance, particularly among E. coli strains. Further investigation is needed to explore the consequences of such epidemiological changes.
定期监测细菌流行病学有助于评估所采用的抗菌策略。本研究的目的是揭示未选择的血液系统癌症住院患者感染流行病学的演变趋势以及新出现的抗生素耐药性。
分析了在16个月期间连续入住单一机构的823例患者发生的发热/感染事件。预期中性粒细胞减少超过7天的患者使用左氧氟沙星预防。
364例患者（44.2%）出现发热，187例（22.7%）记录有感染，其中临床感染（6.1%）或微生物学感染（16.6%）。39.4%的病例使用了左氧氟沙星预防，仅在中性粒细胞减少患者中发热事件有所减少，记录的感染频率无差异。在分离出的164种病原体中，革兰阴性菌（49.4%）多于革兰阳性菌（40.9%），大肠杆菌最为常见（23.2%）。氟喹诺酮耐药和甲氧西林耐药是最常见的抗生素耐药类型，分别发生在56.1%的细菌分离株和66.7%的葡萄球菌中。耐氟喹诺酮大肠杆菌占所有分离株的20.1%，占大肠杆菌的86.8%。氟喹诺酮耐药危险因素的多变量分析确定预防（P<0.001）和中性粒细胞减少超过7天（P = 0.02）为独立因素。甲氧西林耐药与预防（P = 0.041）和中心静脉导管（P = 0.036）独立相关。耐氟喹诺酮菌株感染并未显示出更差的结局。
近年来，血液系统患者的细菌流行病学已出现向革兰阴性菌转变趋势。氟喹诺酮耐药正成为主要的抗菌耐药类型，尤其是在大肠杆菌菌株中。需要进一步研究以探讨这种流行病学变化的后果。
