Characteristic of Clinical Distribution and Drug Resistance of Pathogenic Bacteria in Lower Respiratory Tract Infection / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To investigate the characteristic of clinical distribution and drug resistance of pathogenic bacteria in lower respiratory tract infection. METHODS Bacterial culture of the lower respiratory tract samples collected from patients who were admitted from Jan to May 2008 was done.The bacteria identification and drug sensitivity tests were done by VITEK bacterium identifying and drug sensitivity analyzing system. RESULTS A total of 502 pathogens were isolated,in which 340 strains of Gram-negative bacteria(67.7%),32 strains of Gram-positive cocci(6.4%)and 130 strains of fungi(25.9%).Of all the 372 strains of bacteria,the most common pathogens in turn were Acinetobacter baumannii,Pseudomonas aeruginosa,Klebsiella pneumoniae and Escherichia coli,respectively.Non-fermenters were the dominant pathogens in intensive care unit(ICU)and the surgery wards,Enterobacteriaceae and fungi were the dominant pathogens in the non-operation wards.Of A.baumannii strains,the antibiotic resistant rates to imipenem and meropenem were 7.5% and 8.8%,respectively,the resistant rates to the other antibiotics were high(53.8%-100.0%,respectively).Of P.aeruginosa strains,the antibiotic resistant rates to imipenem,meropenem,polymyxicn E,ciprofloxacin,amikacin,tobramycin and gentamicin were 11.1%-27.0%,respectively,The resistant rates to the other antibiotics such as penicillins,cephalosporins and the complex antibiotics containing ?-lactamases inhibitor were 38.1%-100.0%.The ESBLs-producing rate of K.pneumoniae strains(71.7%)was higher than that of E.coli strains(29.1%).K.pneumoniae strains and E.coli strains were all sensitive to imipenem and meropenem,and both of their resistant rates against amikacin were the same(10.9%),but against the other antibiotics the resistance of E.coli strains were more serious than that of K.pneumoniae strains. CONCLUSIONS In our area,non-fermenters are mainly isolated from ICU and the surgery wards.Enterobacteriaceae and fungi are mainly isolated from the non-operation wards.The major pathogens show multi-drug resistance except imipenem,meropenem and amikacin.It′s important to prevent hospital acquired lower respiratory tract infection during the clinical therapy,and it is urgent for rational use of antimicrobial agents according to the results of antibiotics susceptibility tests.