探讨口腔颌面外科住院患者医院感染病原学特征及相关因素。

选取中山大学附属口腔医院2014—2019年收治的口腔颌面外科住院患者共15 876例为研究对象，采用SPSS 26.0软件进行数据分析，计算医院感染患者感染部位分布及感染率；通过细菌培养及药敏试验分离鉴定感染患者的病原菌，以分析感染患者病原菌分布及主要病原菌对抗菌药物的耐药性；通过χ²检验及Logistic回归模型分析医院感染的影响因素。

15 876例口腔颌面外科住院患者发生医院感染188例，感染率为1.18%，感染部位以手术部位（53.68%）及下呼吸道（41.58%）为主；共培养分离病原菌249株，其中革兰阴性菌182株，占73.10%，以铜绿假单胞菌为主；革兰阳性菌64株，占25.70%，以金黄色葡萄球菌为主；真菌3株，占1.20%；分离出的铜绿假单胞菌对亚胺培南的耐药率较高，对左旋氧氟沙星等抗菌药物比较敏感；分离出的肺炎克雷伯菌对氨苄西林耐药率较高，对头孢他啶等抗菌药物比较敏感；分离出的金黄色葡萄球菌对青霉素耐药率较高，对利奈唑胺等抗菌药物比较敏感；单因素分析结果显示，年龄、性别、行气管切开术、行游离皮瓣术及患恶性肿瘤是口腔颌面外科住院患者感染的影响因素（P<0.05）；多因素Logistic回归分析结果显示，年龄、行气管切开术及患恶性肿瘤是口腔颌面外科住院患者感染的相关因素（P<0.05）。

革兰阴性菌是引起口腔颌面外科住院患者医院感染的主要病原菌，临床应针对病原菌的特征，合理使用抗菌药物，以提高抗感染治疗质量；影响口腔颌面外科住院患者医院感染的因素较多且相互关联，临床应针对感染相关因素制定系统化的预防干预措施，以降低医院感染发生率。

To investigate the characteristics of pathogenic bacteria and related factors of nosocomial infection in the maxillofacial surgery inpatients.

A total of 15 876 patients with oral and maxillofacial surgery admitted to Hospital of Stomatology of Sun Yat-sen University from 2014 to 2019 were selected as the research subjects. SPSS 26.0 software was used for data analysis. The incidence of nosocomial infections in the patients was assessed. The strains of the infected patients were isolated and identified through bacterial culture. The characteristics of the pathogens were analyzed through drug susceptibility tests. The influencing factors of nosocomial infection was analyzed through single factor (χ² test) and multiple factors (Logistic regression model) .

There were 188 cases of nosocomial infection out of 15 876 total cases included in this study. The infection rate was 1.18% and the two main infection sites were the surgical site and lower respiratory tract. 249 samples from nosocomial infection cases were co-cultured for pathogenic result and bacteria groups were isolated, out of which there were 182 gram-negative bacteria samples (accounting for 73.10%, mainly Pseudomonas aeruginosa) , 64 samples showed of gram-positive bacteria (taking up for 25.70%, mainly Staphylococcus aureus) , 3 fungi results (accounting for 1.20%) . Isolated Pseudomonas aeruginosa showed high resistance rate to imipenem, but is more sensitive to other antibacterial drugs such as levofloxacin. Isolated Klebsiella pneumoniae has a high resistance rate to ampicillin but is more likely to be controlled by ceftazidime. The isolated Staphylococcus aureus showed relatively higher resistant chance to penicillin but was more sensitive to linezolid. The results of univariate analysis showed that age, gender, tracheotomy, free flap surgery and malignant tumors were the influencing factors of nosocomial infection in patients of oral and maxillofacial surgery (P<0.05) . The results of multivariate logistic regression analysis showed that, factors of age, tracheotomy and malignant tumors are considered related to infection (P<0.05) .

Gram-negative bacteria is the main bacterial group that causes infection. Several factors are considered to be counting for the infection and may have interacting effect. Clinical interventions should be made to prevent or reduce infection cases. According to the characteristics of pathogenic bacteria, it provides the basis for rational use of antibiotics in clinical practice, so as to improve the quality of anti-infection treatment.