ABSTRACT
OBJECTIVE To investigate the bacterial resistance of nonfermentatice gramnegative bacilli(NFGNB) in recent 5 years. METHODS The bacteria identification was done by VITEK Auto Microbe System and antimicrobial susceptibility tests were conducted by Kirby-Bauer method. RESULTS Among the 3069 strains of Gram-negative bacilli,871(28.4%)were Pseudomonas aeruginosa;655(21.4%) were Acinetobacter spp;279(9.1%) were Stenotrophomonas maltophilia.Most of them were isolated from sputum(66.3%),secretion(16.8%) and urine(10.0%),respectively.The antibacterial resistance of P.aeruginosa was as followset imipenem(75.2%),meropenem(78.6%),TMP-SMZ(4.6%),levofloxacin(47.9%),minocycline(33.9%),piperacillin(51.7%),piperacillin/tazobactam(56.0%),ceftazidime(63.6%),cefepime(67.3%),gentamicin(37.2%),ticarcillin-clavulanate(22.8%),aztreonam(29.3%),and ciprofloxacin(63.4%);while the activity against Acinetobacter spp was to aztreonam(12.6%),imipenem(96.9%),meropenem(95.6%),and to other 10 antibiotics(less than 60%),and the activity against S.maltopbnilia was to TMP-SMZ(73.4%),levofloxacin(86.2%),and minocycline(89.8%). CONCLUSIONS Since the isolation and drug resistance rates of NFGNB are high,the combined antibiotics should be used to treat NFGNB infection,such as imipenem,meropenem and others which are sensitive to NFGNB.
ABSTRACT
OBJECTIVE To investigate the incidence of integrons in Pseudomonas aeruginosa strains isolated from blood samples in Peking University People′s Hospital and to analyze the correlation between integrons and drug resistance of P.aeruginosa.METHODS Forty-two strains of clinically isolated P.aeruginosa were collected.The antibiotics susceptibility was tested by K-B methods.Integrase gene of integron was amplified by PCR using degenerate primers.The integrons were classified by restriction fragment length polymorphism(RFLP) analysis of positive PCR products with Hinf Ⅰ restriction enzyme.RESULTS The drug-resistance rates of 42 strains of P.aeruginosa against 20 kinds of antibiotics ranged from 9.5% to 100%.Twenty-three strains were resistant to 12 kinds of antibiotics.Nineteen of the 42 isolates(45.2%) contained integrons,all of which were revealed as class Ⅰ of integrons by RFLP analysis.Neither class Ⅱ nor class Ⅲ of integron was detected.The positive percentage of integrons was increased by years.CONCLUSIONS Class Ⅰ integrons are widespread in isolates from blood samples in our hospital.The presence of integrons is closely associated with multi-drug resistance of P.aeruginosa.