Pathogens distribution and drug resistance in lower respiratory tract infection.

Objective To investigate the pathogenic bacteria and antibiotic resistance in the patients with lower respiratory tract infection to help reasonably utilize antibiotics.Methods By the retrospective methods,we analyzed the pathogens isolated from the sputa of the hospitalized patients with lower respiratory tract infection from September 2007 to September 2008 and their drug resistance.Results There were 201(56.5%)strains of Gram-negative bacilli,99(27.8%)strains of Gram-positive bacteria and 56(15.7%)strains of fungi.The most important Gram-negative pathogens were P.aeruginosa,Escherichia coli,Klebsiella pneumoniae,Acinetobacter baumannii,stenotrophomonas malthilia and Enterobacter cloacae.In view of the resistance,no Staphylococcus species resistant to vancomycin were found,while they were resistant to many other antimicrobial agents.The antibiotic sensitivity tests in vitro showed that sensitive rate of imipenem was the lowest.The resistance rate of ampicillin was the highest,P.aeruginosa and Stenotrophmomas malthilia were resistant to the most antimicrobial agents.Conclusion Gram-negative bacilli are the major pathogens in lower respiratory tract infection and the dominant is conditional pathogen and fungi occupy a fixed ratio.The drug resistance increases constantly.So it is very important to utilize antibiotics reasonably and pay attention to supervising drug resistance.Rational use of antibiotics is important for the containment of bacterial resistance.