感染性心内膜炎患者病原菌分布及耐药性分析

Analysis of pathogen distribution and drug resistance in patients with infective endocarditis

目的分析感染性心内膜炎患者血培养病原菌及其耐药性,为临床合理用药提供参考。方法回顾性研究2013年1月-2017年12月我院临床诊断感染性心内膜炎患者血培养阳性的病例,结合临床病例分析病原微生物特点及其药物敏感性情况。结果166例感染性心内膜炎患者中检出病原菌326株,其中革兰阳性菌248株占76.1%,主要为草绿色链球菌141株(43.3%)、表皮葡萄球菌30株(9.2%)、金黄色葡萄球菌8株(2.5%);革兰阴性菌78株占23.9%,主要为唐菖蒲伯克霍尔德菌23株(7.1%),嗜麦芽寡养单胞菌9株(2.8%),栖稻假单胞菌8株(2.5%)。所检出革兰阳性球菌未发现对万古霉素、利奈唑胺耐药;草绿色链球菌对红霉素、克林霉素耐药率较高,分别为58.6%和71.5%;对青霉素G、氨苄西林、氯霉素、头孢噻肟、头孢曲松、头孢吡肟敏感性较好,基本无耐药发生;表皮葡萄球菌和金黄色葡萄球菌对青霉素G耐药率为100%,对苯唑西林、红霉素、四环素耐药率均大于56.7%。所检出革兰阴性菌中,唐菖蒲伯克霍尔德菌、栖稻假单胞菌对头孢曲松、头孢他啶耐药率为26.5%~56.3%,对其他抗生素均敏感;嗜麦芽寡养单胞菌对米诺环素、复方磺胺甲噁唑和左氧氟沙星均敏感。感染性心内膜炎病原菌逐渐呈对多种抗生素耐药的趋势,近年来出现对头孢噻肟、头孢曲松和头孢吡肟耐药的草绿色链球菌;葡萄球菌对苯唑西林的耐药率高达70.9%;近两年,表皮葡萄球菌对复方磺胺甲噁唑、左氧氟沙星、环丙沙星的耐药率均大于50%,并出现对庆大霉素耐药菌株。革兰阴性菌主要对头孢类抗生素耐药,且耐药率有升高趋势。结论近年来,感染性心内膜炎已成为医院常见的一种感染性疾病,所感染的病原菌主要为革兰阳性球菌。随着抗生素的广泛使用,导致病原菌对抗菌药物的耐药性明显增强,耐药菌株不断涌现给临床治疗带来极大的困难。因此,密切关注感染性心内膜炎病原菌的分布和耐药性变迁,对指导临床及早有效的诊断及治疗,提高患者生存率具有重大意义。

Objective To analyze the blood culture pathogens and their drug resistance in patients with infective endocarditis, and provide reference for clinical rational drug use. Methods Retrospective study was carried out on patients with infective endocarditis diagnosed clinically in our hospital from January 2013 to December 2017. Pathogenic microorganism characteristics and drug sensitivity were analyzed in combination with clinical cases. Results A total of 326 pathogenic bacteria were detected in 166 patients with infective endocarditis. Among them, 248 strains of Gram-positive bacteria accounted for 76.1%. There were mainly 141 strains of Streptococcus viride (43.3%), 30 strains of Staphylococcus epidermidis (9.2%), and 8 strains of Staphylococcus aureus (2.5%). 78 strains of Gram-negative bacteria accounted for 23.9%. There are mainly 23 strains of Burkholderia gladiolus (7.1%), 9 strains of Stenotrophomonas maltophilia (2.8%), and 8 strains of Flavimonas oryzihabitans (2.5%). Gram-positive cocci were not found to be resistant to vancomycin and linezolid. The resistance rate of Streptococcus viridans to erythromycin and clindamycin was 58.6% and 71.5%, respectively;penicilin G, ampicillin, chloramphenicol, cefotaxime, ceftriaxone, and cefepime showed better sensitivity and substantially no drug resisance. The resistance rates of Staphylococcus epidermidis and Staphylococcus aureus to penicillin G were 100%, and the resistance rates to oxacillin, erythromycin and tetracycline were more than 56.7%. Among the Gram-negative bacteria detected, the resistance rates of Burkholderia gladiolus and Flavimonas oryzihabitans to ceftriaxone and ceftazidime were 26.5%~56.3%, and Burkholderia gladiolus and Flavimonas oryzihabitans were sensitive to other antibiotics. Stenotrophomonas maltophilia was sensitive to minocycline, compound neotamine, and levofloxacin. Infective endocarditis pathogens showed a trend of resistance to various antibiotics gradually. In recent years, Streptococcus viridis appeared resistant to cefotaxime, ceftriaxone and cefepime. The resistance rate of Staphylococcus to oxacillin was as high as 70.9%. In recent two years, the resistance rates of Staphylococcus epidermidis to compound sulfamethoxazole, levofloxacin, and ciprofloxacin were more than 50%, and gentamicin-resistant strains appeared. Gram-negative bacteria were mainly resistant to cephalosporins, and their resistance rates were increasing. Conclusion Infectious endocarditis has become a common infectious disease in hospitals in recent years. Gram-positive cocci are the main pathogens. With the widespread use of antibiotics, the resistance of pathogenic bacteria to antibiotics has increased significantly, and the emergence of drug-resistant strains has brought great difficulties to clinical treatment. Therefore, we should pay close attention to the distribution of pathogenic bacteria and the change of drug resistance in infective endocarditis, so as to make early and effective diagnosis and treatment and improve the survival rate of patients.