High Concentration Glucose On Acinetobacter Baumannii Biofllm Formation Ability

Acinetobacter baumannii is a non-fermenting Gram-negative bacteria widely found in nature and in the hospital environment, pathogens belongs conditions, can cause a range of nosocomial infections, such as pneumonia, urinary tract infections,sepsis secondary to meningitis, wound infection, a serious threat to the lives of patients. In recent years, with the broad-spectrum antibiotics, in particular, the increased resistance to carbapenems wide range of applications as well as medical implants, Acinetobacter serious nosocomial infections caused by the bacillus increasingly serious infection,morbidity and mortality increased rapidly. A long time, the bacteria mainly by individual planktonic bacteria, however, recent studies show that the bacteria mainly through the form of a biofilm adhering to the surface of the object to maintain its survival. At the same time, foreign studies have confirmed that high concentrations of glucose can induce the formation of bacterial biofilms. Infections caused by biofilms Acinetobacter baumannii pathogenic. Therefore, the study of the impact of the high concentration of glucose Acinetobacter baumannii biofilm formation, will be provided for the prevention and treatment of the infection which caused the effective ideas and methods.In this study, collected in a hospital Acinetobacter baumannii30, and its resistance determined by agar dilution method; With crystal violet staining semi-quantitative determination of its ability to form biofilms, to filter out the Acinetobacter baumannii which can form biofilm,its culture with different concentrations of glucose, as measured by crystal violet staining, analysis the impact of Acinetobacter baumannii biofilm formation with high concentrations of glucose; three strong positive Acinetobacter baumannii of which form biofilms capacity dynamic monitor with confocal laser scanning microscope,further observed under culture conditions and at different time points in different concentrations of glucose, the impact of Acinetobacter baumannii biofilm formation with high glucose concentration.1. Study on Acinetobacter baumannii biofilm forming ability and its antimicrobial resistance ratesBy crystal violet staining quantitative analysis of the30Acinetobacter baumannii. This30Acinetobacter baumannii cultured with different concentrations of glucose as the experimental group, at the same time set the culture conditions without glucose Acinetobacter baumannii as the control group. Is defined as the average of the negative control the A570value plus the standard deviation Ac, the measured strains, with3holes (A570) on average compared with Ac, strain biofilm forming ability can be divided into four categories:Negative (-):no biofilm formation, A≤Ac; Weakly positive (+):Ac<A≤2×Ac; Moderately positive (++):2×Ac<A≤4×Ac;Strongly positive (+++):A>4×Ac.Above criteria results show, the30Acinetobacter Acinetobacter clinical isolates were biofilm forming ability and formation test were strongly positive.By agar dilution method for the determination of the injection of aztreonam, ceftazidime injection, piperacillin, piperacillin/sulbactam, levofloxacin, cefoperazone/sulbactam, meropenem, amikacin Acinetobacter of Acinetobacter minimum inhibitory concentration (MIC).The resistant rates to ceftazidime, piperacillin and amikacin were96.6%, to cefoperzone/sulbactam and meropenem were86.7%. The strains were resistant to piperacillin/sulbactam and levofloxacin were93.9%,63.6%, respectively All the30isolates had biofilm-forming ability. And all of them were strongly positive for biofilm-forming ability. Therefore, the30Acinetobacter Acinetobacter has a strong biofilm forming ability, and with multiple drug resistance.2. Effects of high glucose on Acinetobacter baumannii biofilm formation abilityFirst statistical distribution of Acinetobacter baumannii specimens of30, found that the majority of the majority of elderly patients (36.7%), the type of specimen mainly sputum specimens (76.7%) patients where the department is mainly concentrated in neurosurgery (36.7%),orthopedics (13.3%), ICU (13.3%) and SICU (10%).Ability to the30biofilm formation was strongly positive Acinetobacter baumannii cultured with different concentrations of glucose (5、7、11.1、16.7、20、30mmol/l),the same semi-quantitative detection of its biofilm formation using crystal violet staining. Semi-quantitative experimental data statistical analysis shows the absorbance upward trend with increasing glucose concentration, after11.1mmol/1, biofilm formation is more than without glucose group(p<0.05),and after11.1mmol/1glucose concentration in each group absorbance values were different (p>0.05), showed a flat trend. This shows that the high concentration of glucose significantly induced Acinetobacter baumannii biofilm formation.3. Confocal laser scanning microscopy observation of high glucose on Acinetobacter baumannii biofilm formationSelected from the30Acinetobacter baumannii biofilm formation strongest three Acinetobacter Acinetobacter as the research object, using different concentrations of glucose culture, in the formation of biofilms on coverslips, respectively inoculated12,24,36,48,60and72h remove the slide, using immunofluorescence technique labeled bacteria and polysaccharides,Confocal laser scanning microscopy(CLSM) concept Acinetobacter baumannii dynamic process of biofilm formation and determine the thickness of the biofilm.With CLSM observation showed that when glucose concentration≥1.1mmol/L, forming mature biofilm’s time is short, Acinetobacter baumannii can be formed around24h,advanced24h than without glucose group; Biofilm thickness data by statistical analysis show, the maximum plus glucose group, the thickness of fall in the range of12-36h, and the maximum value of the thickness of the glucose group without glucose group maximum value (p<0.05).This suggests that the high concentration of glucose significantly induced Acinetobacter baumannii biofilm formation, and will shorten the cycle of biofilm formation.