Detection and Drug Resistance Analysis of Common Pathogenic Bacteria in Lower Respiratory Tract Infection

[Objective]To understand composition and drug resistance of common pathogenic bacteria in lower respiratory tract infection,provide the experimental basis for rational use of antibiotics in clinic.[Methods]Bacterial culture was conducted on qualified sputum specimen from inpatients and outpatients with lower respiratory tract infection in People's Hospital Affiliated to Inner Mongolian Medical College from January 2009 to May 2010.API-20E identification system of France Biomerieux and routine manual method were adopted to the bacteria identification.Drug sensitivity test was conducted by K-B method.[Results]652 strains of pathogenic bacteria were isolated.There were 523(80.2%) strains of Gram-negative bacilli,which mainly included Klebsiella pneumoniae,Escherichia coli,Pseudomonas aeruginosa,Enterobacter cloacae and Citrobacter freundii.There were 129(19.8%) strains of Gram-positive bacteria,which mainly included Staphylococcus aureus and Candida albicans.The drug sensitivity test showed: except Pseudomonas aeruginosa,the resistance rate of Gram-negative bacilli to imipenem was the lowest(0%),and the resistance rate to ampicillin was the highest(mean value was 84.2%).Among Staphylococcus aureus,the isolation rate of Methicillin-resistant Staphylococcus aureus(MRSA) was high(68.5%),and MRSA showed multi-drug resistance except for vancomycin.[Conclusion]The pathogenic bacteria of lower respiratory tract infection in this hospital are dominated by Gram-negative bacilli,and the sensitivity of different bacteria to same antibiotic is different.The antibiotic should be chosen according to the results of drug sensitivity test,so as to reduce the antibiotic resistance in pathogenic bacteria.