骨科创面蜡样芽胞杆菌感染临床特点及耐药性分析

Clinical characteristics and resistance of wound surface infections causing by Bacillus cereus in the department of orthopaedics

目的：探讨骨科创面蜡样芽胞杆菌感染情况、临床特点及耐药性分析,为临床诊断及合理用药提供依据.方法：分析我院自2011年10月至2012年6月临床标本中分离的20株蜡样芽胞杆菌感染的临床资料及实验室结果,其中男18例,女2例;年龄22～67岁,平均（47.30±11.16）岁;病程5～20d.采用营养支持、清创及相应的抗菌药物治疗,蜡样芽胞杆菌感染时,患者贫血貌,低蛋白血症,伤口有污染史.同时与正常组比较,正常组男23例,女7例;平均年龄（45.20±15.05）岁.感染治疗前后通过病原菌培养、创面红肿或渗出情况检查来评估感染控制情况,采用纸片扩散法（K-B法）测定20种抗菌药物的药敏结果.结果：20株蜡样芽胞杆菌在骨科创面感染中检出,其中患者创面污染史16例,营养不良20例,开放性骨折20例,手术时间〉3h 15例;实验室检查总蛋白（49.94±8.24）g/L,白蛋白（29.54±5.45）g/L,血红蛋白（103.20±11.79）g/L,均低于正常组;而白细胞计数（8.35±2.31）×109/L,中性粒细胞绝对值（6.98±1.99）×109/L,超敏C反应蛋白（73.60±55.14）mg/L,肌酸激酶（900.10±1259.12）IU/L,均高于与正常对照组.对青霉素、头孢唑啉、头孢呋辛、头孢他啶、头孢吡肟、复方新诺明、红霉素抑菌圈直径小于15mm,表现耐药;对克林霉素、万古霉素、庆大霉素、环丙沙星、亚胺培南抑菌圈直径大于20mm,对该菌有较高的敏感性.结论：免疫力低下、低蛋白血症同时伴有开放性创伤及污染性创面的骨科患者蜡样芽胞杆菌易感染,治疗应在补充白蛋白、对症支持治疗基础上选择敏感的抗菌药物.

Objective：To study clinical characteristics and resistance of wound surface infections,so as to guide clinical diagnosis and rational administration.Methods：The clinical setting and laboratory results were collected by analyzing 20 strains of Bacillus cereus isolated from clinical samples in patients from our hospital from October 2011 to June 2012,including 18 males and 2 females,ranging in age from 22 to 6 7 years old,averaged（47.30±11.16） years old.The courses of disease ranged from 5 to 20 days.All the patie nts were treated with nutrition support therapy,debridement and the corresponding antibiotic therapy.The patients had anemia,low protein hyperlipidemia and wound contamination history while Bacillus cereus in fected.Thirty people were selected as normal group,including 23 males and 7 females,with an average age of （45.20±15.05） years old.Infection control condition was assessed by comparing culture for pathogens an d patients wound redness or exudation cases before and after treatment.Antimicrobial susceptibility test was conducted by K-B method.Results：A total of 20 stains of Bacillus cereus were isolated from wound surface infections in department of orthopedics of our hospital.Among them,the infections were correlated with the wound contamination（16/20）,malnutrition（20/20）,and open-fracture （20/20）,operation time （15 cases〉3 h）.The laboratory blood test showed that the levels of TP [（49.94±8.24） g/L],ALB [（29.54±5.45 ） g/L] and Hb [（103.20±11.79） g/L ] in the infection group was lower than those of control group;in the contrast,the levels of WBC[（8.35±2.31）×109/L],NEUT[（6.98±1.99）×109/L ],hs-CRP[（73.60±55.14） mg/L] and CK [（900.1 0±1 259.12） IU/L] were higher in the infection group than those of control group,and the differences were statistically significant （P〈0.01）.The diameter of inhibition zone in penicillin,cefazolin,cefuroxime,ceftazidime,cefepime,cotrimoxazole,erythromycin were less than 15 mm,and suggested that Bacillus cereus resisted to these antibiotics.However,the diameter of inhibition zone in clindamycin,vancomycin,gentamicin,ciprofloxacin,imipenem were larger than 20 mm and this data indicated that the bacteria were highly sensitive to these antibiotics.Conclusion：Orthopedic patients who immunocompromised,hypoproteinemia and accompanied by open wounds and contaminated wound susceptible to infect Bacillus cereus;sensitive anti microbial drugs should be selected on the basis of supplement albumin,symptomatic and supportive treatment.