Abstract: Background　With the application of broad-spectrum antibiotics，the pathogenic bacteria and drug susceptibility spectrum of diabetic foot infections have changed significantly，and studies on the distribution and drug susceptibility of pathogenic bacteria in patients with recurrent diabetic foot infections are rare.Objective　To study the distribution characteristics of pathogenic bacteria in different severity grades of recurrent infection of diabetic foot in patients with diabetes mellitus，and to provide empirical basis for antimicrobial therapy for patients with recurrent infection of diabetic foot.Methods　A total of 52 cases with recurrent diabetic foot infection hospitalized in the Department of Endocrinology，Fuyang People's Hospital from July 2016 to July 2018 were selected.Bacterial culture and drug sensitivity experiments were conducted on their secretions，and the severity of infection was analyzed，and the relationship between the severity of infection and the distribution of pathogenic bacteria was statistically analyzed.Results　Among 52 patients with recurrent diabetic foot infection，there were 19 cases of mild infection，20 cases of moderate infection，and 13 cases of severe infection.Gram-positive coccal infection （14/19） and single infection （17/19） were the main cases of mild infection.Gram-negative bacilli infection （15/28） and mixed infection （6/13） were the main cases of severe infections.A total of 70 pathogenic bacteria strains were cultured from 52 patients with recurrent infection of diabetic foot，including 34 strains（48.6%） of gram-positive cocci，29 strains（41.4%） of gram-negative bacillus，and 7 strains（10.0%） of fungi.Gram-positive cocci，such as  staphylococcus aureus，enterococcus faecalis and streptococcus ，were more sensitive to  linezolid and vancomycin ，with lower drug resistance，and more serious drug resistance to penicillin and clindamycin.Gram-negative bacteria，such as escherichia coli，proteus and klebsiella pneumoniae，showed low resistance to carbapenems and serious resistance to third-generation cephalosporins.The fungi were more resistant to fluconazole and sensitive to carpofennet and amphotericin B.Conclusion　With the aggravation of recurrent infection of diabetic foot，the infection rate of pathogenic bacteria from Gram-positive cocci decreased，and the infection rate of Gram-negative bacilli increased.The more severe the infection，the higher the chance of having mixed infection.Patients with severe recurrent infection have certain resistance to conventional antibiotics，and the use of antibiotics should be strictly controlled in the clinical treatment of diabetic foot.

Key words: Diabetic foot, Recurrence, Infection, Anti-bacterial agents, Resistance

摘要： 背景　随着广谱抗菌药物的应用，糖尿病足感染患者病原菌及药敏谱发生了显著变化，并且对反复发生糖尿病足感染患者的病原菌分布及药物敏感性研究少见。目的　研究糖尿病患者糖尿病足复发感染不同严重程度分级中病原菌分布特点，为糖尿病足复发感染患者提供抗菌药物经验性治疗依据。方法　选取2016年7月—2018年7月阜阳市人民医院内分泌科住院的糖尿病足复发感染患者52例，对其分泌物进行细菌培养及药物敏感性实验，并对感染严重程度进行分析，统计分析感染严重程度与病原菌分布的关系。结果　52例糖尿病足复发感染患者中轻度感染19例，中度感染20例，重度感染13例。轻度感染患者以革兰阳性球菌感染（14/19）及单一感染（17/19）为主；重度感染患者以革兰阴性杆菌感染（15/28）及混合感染（6/13）为主。52例糖尿病足复发感染患者中共培养出70株病原菌，其中革兰阳性球菌34株（48.6%），革兰阴性杆菌29株（41.4%），真菌7株（10.0%）。革兰阳性球菌如金黄色葡萄球菌、粪肠球菌及链球菌等对利奈唑胺、万古霉素较为敏感，耐药性较低，对青霉素、克林霉素耐药性较为严重；革兰阴性杆菌如大肠埃希菌、变形杆菌及肺炎克雷伯菌对碳青霉烯类耐药性低，对三代头孢类等耐药性较为严重；真菌对氟康唑耐药性较高，对卡泊芬净、两性霉素B较为敏感。结论　随着糖尿病足复发感染程度加重，病原菌由革兰阳性球菌感染率下降，革兰阴性杆菌感染率升高。感染程度越重，混合感染机会越高。重度复发感染患者对常规抗菌药物具有一定耐药性，在糖尿病足的临床治疗上需严格控制抗菌药物的使用。

关键词: 糖尿病足, 复发, 感染, 抗菌药, 耐药性