小儿院内获得性肺炎产超广谱β-内酰胺酶细菌的耐药性及危险因素分析

目的　随着第3代抗生素广泛应用,导致产超广谱β 内酰胺酶(ESBLs)的耐药菌株不断增加,引 起院内感染的流行。该研究旨在了解院内获得性肺炎(HAP)患儿产ESBLs菌的产生、对12种抗生素的耐药情况 及对产ESBLs危险因素进行分析。方法　应用纸片扩散法和双纸片协同试验对HAP患儿痰液分离的革兰阴性杆 菌进行ESBLs检测,比较产ESBLs组与非产ESBLs菌组对亚胺培南等12种抗生素体外耐药情况,对HAP产ESBLs 菌的危险因素进行Logistic多因素回归分析。结果　109株革兰氏阴性杆菌中,检出ESBLs阳性菌43株,总检出率 为39.4%,分别为:大肠杆菌13.8%,肺炎克雷伯菌9.2%,阴沟肠杆菌8.3%,其它克雷伯菌4.6%,其它肠杆菌 3.7%。产ESBLs菌组对第1,2,3代头孢耐药率明显高于非产ESBLs组。两组对亚胺培南耐药率低(0～11%),对 喹诺酮类、氨基糖甙类大多在40%以下。产ESBLs菌的危险因素依次为:第3代头孢使用≥3d、气管插管、留置鼻 饲管、反复吸痰、住ICU。结论　治疗产ESBLs菌可用亚胺培南或喹诺酮类和氨基糖甙类药物。加强消毒隔离、合 理使用抗生素、避免侵入性操作有助于减少ESBLs菌的发生。

Drug resistance of extended spectrum beta-lactamase-producing bacteria and risk factors for this bacteria infection in children with hospital acquired pneumonia

Objective With the extensive use of the third-generation antibiotics, the resistant strains of extended spectrum β-lactamases (ESBLs)-producing bacteria are constantly increasing resulting in an outbreak of nosocomial infectious. This study aimed to investigate the positive rate of ESBLs-producing bacteria and the incidence of their drug resistance to 12 common antibiotics as well as risk factors associated with this bacteria infection in children with hospital acquired pneumonia (HAP). Methods ESBLs-producing bacteria were examined by the disc diffusion confirmatory test and the double disc synergy test in Gram-negative bacteria from sputum in children with HAP. The incidence of drug resistance to 12 common antibiotics was compared between the positive and negative ESBLs-producing bacteria. The risk factors for ESBLs producing bacteria infection were investigated by logistic regressive analysis. Results Forty-three positive ESBLs-producing bacteria strains were isolated from 109 Gram-negative bacteria strains in 95 children with HAP, with a positive rate of 39.4%. Of the bacteria, Escherichia coli accounted for 13.8%, 9.2% for Klebsiella pneumoniae, 8.3% for bowel bacilli, and 8.3% for other bacteria. The incidence of drug resistance of positive ESBLs- producing bacteria to cefozolin, ceclor and cefotaxime was significantly higher than that of non-ESBLs-producing bacteria. In either positive or negative ESBL-producing bacteria, the incidence of drug resistance to imipenem was low (0-11%) and to quinolone and aminoglycoside it was below 40%. Logistic regressive analysis showed that the independent risk factors for ESBLs-producing bacteria infection included the duration of cefotaxime treatment (>3 d), admission to the Intensive Care Unit and invasive operations. The first factor was a predominant one. Conclusions Imipenem, quinolone and aminoglycoside may be recommended in the treatment of ESBLs-producing bacteria infection. Risk for ESBLs-producing bacteria infection is multifactorial. It is necessary to reasonably use antibiotics, stress the asepsis principle and reduce invasive operations as much as possible in order to decrease ESBLs-producing bacteria infection.