Study on the Mechanism of Trimethoprim-Sulfamethoxazole Resistance in Stenotrophomonas Maltophilia / 现代检验医学杂志

Objective Class 1 integrase(intI 1),qacE△1-sul1 and sul2 genes were detected in trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia by PCR to assess the relationship between the antibiotic resistance mechanism for trimethoprim-sulfamethoxazole (TMP-SMZ)and these genes distribution.Methods S.maltophilia isolates were collected from patients treated in Affilitated hospital of Nanjing University of TCM during January to May in 2013,DNA was ab-stracted by boiling method and genes were detected by polymerase chain reaction.Results intI 1 genes were observed posi-tive in 25 of 28 strains resistant for TMP-SMZ,qacE△1-sul1 genes were positive in 21 while sul2 genes positive in 15,the positive rates of intI 1,qacE△1-sul1 and sul2 genes were 89.29%,75% and 53.57%;in 18 trimethoprim-sulfamethoxazole sensitive strains,5 were intI 1 positive,4 were qacE△1-sul1 positive while sul2 were none,the positive rates of intI1 and qacE△1-sul1 were 27.78% and 22.22%.Conclusion Most of stenotrophomonas maltophilia resisted trimethoprim-sulfa-methoxazole had intI 1,qacEΔ1-sul 1 and sul2 genes.

Relationship Between qacE△1-sul1 Gene and IntⅠ1 Gene and Multidrug Resistance in Acinetobacter baumannii Isolates from Children / 中华医院感染学杂志

OBJECTIVE To investigate the disinfectant-sulfanilamide resistance gene(qacE△1-sul1)and integrase gene(IntⅠ1)of Acinetobacter baumannii(ABA)isolated in pediatric clinic and analyze the relationship between these genes and multidrug resistance.METHODS Twenty eight strains of A.baumannii were collected and isolated from the sputum culture in the deep trachea of children with pneumonia during 2006.Identification of bacteria and susceptibility test by VITEK-32 automicroscan using GNI and GNS cards,were undertaken,qacE△1-sul1 gene and IntⅠ1 gene were analyzed by polymerase chain reaction(PCR).RESULTS Three of 28 strains of A.baumannii showed multidrug resistance,the positive rate was 10.71%.A.baumannii 4 strains were resistant to sulfamethoxazole/trimethoprim(SXT)with the positive rate 14.29%.Eleven strains that carrying qacE△1-sul1 genes and 4 strains carrying IntⅠ1 genes were detected,the positive rate was 39.29% and 14.29%,and qacE△1-sul1 and IntⅠ1 genes positive strains of A.baumannii were resistant to SXT,the other 7 qacE△1-sul1 positive strains were sensitive to SXT.CONCLUSIONS The main drug resistance in ABA resistant to SXT is to obtain qacE△1-sul1 gene.It should be paid attention to qacE△1-suⅠ1 positive but sensitive to SXT strains.It indicates that the strain carrying integron Ⅰ may show multidrug resistance.

Genetic Marker of Class Ⅰ Integron and Transposable Element of Acinetobactor baumannii Isolated from ICU / 中华医院感染学杂志

OBJECTIVE To study the existence status of class Ⅰ integron and transposable element of multi-resistant Acinetobactor baumannii isolated form ICU of Yinzhou People′s Hospital in Ningbo. METHODS The samples of 20 A.baumannii isolates were collected from Oct 2007 to Jul 2008.The susceptibility to 32 antibiotics of the isolates was measured.The genetic markers of integron qacE△1-sul1 and transposable element tnpU were analyzed by polymerase chain reaction(PCR).The PCR products of tnpU or qacE△1-sul1 were sequenced for determination. RESULTS In the 20 ABA isolates,the positive rate of class Ⅰ integron qacE△1-sull was 75%,and the positive rate of transposable element tnpU was 55.0%. CONCLUSIONS The positive rate of the integron qacE△1-sul1 and transposable element tnpU for multi-resistant A.baumannii is high in Yinzhou People′s Hospital in Ningbo.It should be reevaluated the preventative role of chlorhexidine for operation.

Detection of qacE△1-sul1 in Acinetobacter baumannii Isolated from Xinjiang and Its Clinical Significance / 中华医院感染学杂志

OBJECTIVE To study the antibiotic resistance gene of qacE△1-sul1 in Acinetobacter baumannii isolated from inpatients in Urumqi and the distribution and difference of qacE△1-sul1 genotype in Xinjiang. METHODS Bacterial strains were identified by system of API and antibiotic susceptibility test was detected by K-B and microdilution methods according CLSI.PCR was used to determine the gene of qacE△1-sul1 and compared with the sequences in GenBank. RESULTS Antibiotic resistance phenotypes showed the resistance rate to cefataxime and tetracycline was the highest(100.0%),but that to cefoperazone/sulbactam was the lowest.The positive rate of qacE△1-sul1 gene in A.baumannii was 52.2%. CONCLUSIONS High resistance in A.baumannii is found in Xinjiang.The positive rate of qacE△1-sul1 is high.Strengthening epidemiology surveillance of resistance carried by integron-carrying gene is important.

Detection of qacE△1-sul1 Gene in Pseudomonas aeruginosa Isolated from Burned Patients and Its Clinical Significance / 中华医院感染学杂志

OBJECTIVE To investigate the disinfectant-resistant gene qacE△1-sul1 in Pseudomonas aeruginosa isolated from burned patients. METHODS GNS-448 and K-B tests were performed to detect the susceptibility of 19 kinds of antimicrobial agents against these strains. Genotype was analyzed by polymerase chain reaction(PCR) and verified by DNA sequencing. RESULTS The 32 strains isolated were all resistant to ampicillin,cefuroxime,cefoxitin,SMZ/TPM. The sensitive rates to amikacin and gentamicin were 68.0%,and 46.9%,respectively,the resistant rates to imipenem and meropenem were 68.8% and 59.4%,respectively. The positive rate of gene qacE△1-sul1 was 50.0%. CONCLUSIONS The resistance of P. aeruginosa isolated from burned patients is a serious issue.There is high positive percentage of qacE△1-sul1 gene in P. aeruginosa isolated from burned patients.