Study On The Mechanism Of Aminoglycosides Resistance In Pseudomnas Aeruginosa

Aims:To study the main mechanism of Aminoglycosides resistance in Pseudomonas aeruginosa isolated in our hospital and epidemiology distribution of the drug resistant strain. Guide the rational use of drug in the clinical, prevent the develop of the drug resistant strain and extensive outbreak.Methods:To select the strains of the multiple resistance to Aminoglycisides, including gentamicin, tobramycin, netilmicin, Amikacin,in our hospital 156 isolates from January,2009 to October,2010 by using K-B method. The drug resistance genes which were in the strains resistanted at least 3 drugs were analyzed by the PCR. The drug resistance genes of the reaction were armA,rmtB,aac(3')-â… b and aac(6')-â…¡.The PCR products were sequenced by the Illumina Hiseq 2000 sequenator, and then use the BLAST program to analyse the sequence alignments and analyses the performs. Contrastive analysis the strains'isolate rate in clinical, which contain different drug resistance genes, and the status of the distribution of the infective patients.Results:1,The clinical isolating rate of the strains of the multiple resistance to Aminog-lycisides in Pseudomonas aeruginosa.There are 30 strains resistance to gentamicin, tobramycin and netilmicin in the 156 isolates during Janary,2009 to October,2010 in our hospital.The isolating rate is 19.2%.And it has 3 strains also resistance to Amikacin.2,The detection of the four drug resistance genes.The results of 30 strains isolated genes for PCR amplification are:there are 3 Pseudomonas aeruginosas expressing the rmtB gene,21 Pseudomonas aeruginosas expressing the aac(3')-â… b gene and 7 Pseudomonas aeruginosas expressing the aac(6')-â…¡gene .The isolating rates are 10%,70%,23.3% respectively.3,The isolating rate of the multiple resistance to Aminoglycisides Pseudomonas aeruginosas in different clinical divisions.There are 19 Pseudomonas aeruginosas isolated in the department of neurosurgery,4 Pseudomonas aeruginosas isolated in the department of Respiratory Medicine,and 3 Pseudomonas aeruginosas isolated in the department of neurology in the 30 strains of the multiple resistance to Aminoglycisides.The isolating rates are 63.4%,13.3%,10% respectively.Conclusion:The isolating rate of the multiple resistance to Aminoglycisides Pseudomonas aeruginosas which are seprated from our hospital in recent two years is lower than other areas in our country. The Pseudomonas aeruginosas are more sensitive to the Amikacin than any other reports. The mainly drug resistance gene which is isolated from the multiple resistance to Aminoglycisides Pseudomonas aeruginosas is aac(3')-â… b;rmtB is the most important kind of the 16S rRNA methylases separated from the multiple resistance to Aminoglycisides Pseudomonas aeruginosas.The drug resistance genes especially the 16S rRNA methylases could cause the resistance spread in the bacterial species through the transposon, the plasmid and the integron. As we know, the multilple resistance strains can be developed through the different mechanisms'joint action. The phenomenon of no reasonable use of the antibiotics can make the Pseudomonas aeruginosas resistance stronger to the Aminoglycosides especially to the Amikacin, causing the fast spread of the 16S rRNA methylases in the bacterial genus.The most important distribution of the multiple resistance to Aminoglycisides Pseudomonas aeruginosas is the department of neurosurgery, and to cut off the transmission way is the key of the research.