Antibiotic-Resistance-in-Nosocomial.ppt

Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,Knowledge Discovery in Microbiology Data:Analysis of Antibiotic Resistance in Nosocomial Infections,Antibiotic Resistance in Nosocomial Infections,3-40%of patients admitted to hospital acquire an infection during their stay,and that the risk for hospital-acquired infection,or,nosocomial infection,has risen steadily in recent decades.,The frequency depends mostly on the type of conducted operation being greater for“dirty”operations(10-40%),and smaller for“pure”operations(3-7%).E.g.such serious infectious complication as postoperative meningitis is often the result of nosocomial infection.,Antibiotics,are the drugs that are commonly used to fight against infections caused by bacteria.,According to the Center for Disease Control and Prevention(CDC)statistics,more than,70%of the bacteria that cause hospital-acquired infections are,resistant,to at least one of the antibiotics most commonly used to treat infections,.,Analysis of the microbiological data included in,antibiograms,collected in different institutions over different periods of time is considered as one of the most important activities to restrain the spreading of antibiotic resistance and to avoid the negative consequences of this phenomenon.,1,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,How antibiotics work,Inhibition of nucleic acid synthesis,Rifampicin;Chloroquine,Inhibition of protein synthesis,Tetracyclines;Chloramphenicol,Action on cell membrane,Polyenes;Polymyxin,Interference with enzyme system,Sulphamethoxazole,Action on cell wall,Penicillin;Vancomycin,penicillin works by blocking the formation of peptide bonds in the bacterial cell wall and thereby weakens it,leaving the bacterium susceptible to osmotic lysis,2,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,Antibiotic sensitivity of different bacteria,Comparing the antibiotic sensitivity of different bacteria,Jim Deacon,Institute of Cell and Molecular Biology,The University of Edinburgh,3,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,The emergence of antibiotic resistance,Effects of different antibiotics on growth of a,Bacillus,strain.The right-hand image shows a close-up of the novobiocin disk(marked by an arrow on the whole plate).In this case some individual mutant cells in the bacterial population were resistant to the antibiotic and have given rise to small colonies in the zone of inhibition.,Jim Deacon,Institute of Cell and Molecular Biology,The University of Edinburgh,4,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,How Antibiotic Resistance Happens,In spontaneous DNA mutation,bacterial DNA may mutate spontaneously.Drug-resistant tuberculosis arises this way.,In a form of microbial sex called transformation,one bacterium may take up DNA from another bacterium.Pencillin-resistant gonorrhea results from transformation.,Resistance acquired from a small circle of DNA called a plasmid,that can flit from one type of bacterium to another.,A single plasmid can provide a slew of different resistances.,In 1968,12,500 people in Guatemala died in an epidemic of Shigella diarrhea.The microbe harbored a plasmid carrying resistances to four antibiotics!,6,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,How Antibiotic Resistance Happens,Horizontal Gene Transfer,(,Grace Yim and Fan Sozzi),7,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,Mechanisms of Antibiotic Resistance,Grace Yim and Fan Sozzi,8,ISMIS99 Warsaw June 8-11,1999Kaiserslautern,Germany,April 10-13,2005,