Study On Drug Resistance Of Common Gram-negative Bacilli Isolated From Clinical Spencimens Of Hospitalized Patients And Analysis Of Disinfectant-resistant Gene QacEΔ1-sul1

Objective:To investigate the drug resistance of common gram-negative bacilli to regular antibiotics and detect the disinfectant-resistant genes, providing a scientific basis for clinical treatment of infectious diseases.Methods:All isolated strains were identified by BD Phoenix automated microbiology system (BD Phoenix100). Antibiotic sensitivity analysis of the isolated strains were taken by Kirby-Bauer method, and the disinfectant-resistant gene (qacEΔ1-sull) was detected by polymerase chain reaction (PCR).Results:①208gram-negative bacilli were isolated from clinical specimens, including Escherichia coli (49strains), Klebsiella pnenmoniae(53strains), Enterobacter cloacae(10strains), verdigris Pseudomonca (48strains) and Acinetobacter baumannii(48strains), which were mainly distributed in intensive care unit (ICU), respiratory and neurological department.②Among the commonly used antibiotics in clinical treatments, the drug resistance rates of enterobacteria to Amikacin, Imipenem, Meropenem, Piperacillin/Tazobactam and Cefoperazone/Sulbactam were less than20%, while the rate to Ampicillin was higher than80%.③Among the isolated non-fermentative bacteria, the resistance rates of verdigris Pseudomonca to Amikacin, Tobramycin, Piperacillin/Tazobactam and Cefoperazone/Sulbactam were less than30%. while the resistance rates to Cefazolin, Cefuroxime, Ampicillin. Ampicillin/Sulbactam and Nitrofurantoin were higher than90%. Moreover, drug resistance of Acinetobacter baumannii was strictly high. To Piperacillin/Tazobactam and Cefoperazone/Sulbactam the rates were less than45%, while to Cefazolin, Cefuroxime and Nitrofurantoin, the rates were more than90%.④The104out of208(50%) strains carried qacEΔ1-sull gene detected by PCR. The positive rate of Acinetobacter baumannii carrying qacEA1-sull gene that was the highest (75%). Escherichia coli was69.4%. The positive rate of Acinetobacter baumannii and Escherichia coli carrying qacEAl-sull gene were higher than other bacteria strains(P<0.05).⑤The42strains carrying qacEΔ1-sull gene out of208(71.2%) strains in ICU were identified, which was obviously higher than respiratory and neurological department(P<0.05). Conclusions:①mong all the departments, the distribution of gram-negative bacilli from ICU is the highest, suggesting that patients in ICU with poor immunity, using ventilator or receiving invasive operations like tracheal intubation and taking antibiotics for a long time should be paid more attention to the infection of gram-negative bacilli.②Escherichia coli and Klebsiella pnenmoniae (belonging to enterobacteria) are severely muti-drug resistant, but Imipenem and Meropenem are still the first choice to treat infections of Escherichia coli and Klebsiella pnenmoniae.③Verdigris Pseudomonca and Acinetobacter baumannii (belonging to non-fermentative bacteria) are highly resistant to common antibiotics, while their infections can be effectively treated by Piperacillin/Tazobactam and Cefoperazone/Sulbactam.④Among the isolated gram-negative bacilli, the positive rate of qacEAl-sull gene is high, especially Verdigris Pseudomonca and Escherichia coli, indicating that the usage of antibiotics and disinfectants should be more strictly controlled.