Shahcheraghi F, Akbari Shahmirzadi N, bbasalipour Bashash M, Jabbari H, Amirmozafari N. Detection of blaCTX ,blaTEMbeta-lactamase genes in clinical isolates of Acinetobacterspp. from selected Tehran hospitals. Iran J Med Microbiol 2009; 3 (1) :1-9
URL:
http://ijmm.ir/article-1-135-en.html
1- Department of Microbiology, Pasteur Institute of Iran, Tehran, Iran , shahcheraghifereshteh@yahoo.com
2- Department of Microbiology, Pasteur Institute of Iran, Tehran, Iran
3- Center for Environmental Research(CER), Digestive Diseases Research Center (DDRC), HCV Research Group, Iranian Research Center for HIV/AIDS(IRCHA),Tehran University of Medical Sciences(TUMS), Tehran, Iran
4- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
Abstract: (15745 Views)
Background and Objectives: Due to importance and prevalence of ESBL producing isolates in nosocomial
infections, this study was undertaken with the aims to determine antibiotic susceptibility patterns,
identification of ESBL producing isolates and detection of blaCTX
,blaTEM of Acinetobacterspp in clinical
isolates from selected Tehran hospitals.
Material and Method: Ninety five isolates of Acinetobacter were collected from Tehran’s hospitals.
Susceptibility patterns of various antibiotics and MIC for ceftazidime were determined by disk diffusion and
micro broth dilution methods respectively based on CLSI protocols. The ESBL producers were screened by
phenotypic confirmatory test. PCR was used for detection of blaCTX and blaTEM genes.
Results:The lowest and highest resistance rates to investigated antibiotics were seen against colistin (4.2%)
and cefexime (100%) respectively. By using PCT, 18.9% of the isolates were ESBL positive. About 83.1 %
of Acinetobacter isolates showed MIC ≥64 µg/ml to ceftazidime, however only 18.9% of isolates were
ESBL producer. Based on the results from PCR technique,1.2% and 12.8% of the isolates were TEM and
CTX positive respectively.
Conclusion:The rate of MIC to ceftazidime and presence of blaTEM and blaCTX among ceftazidime resistant
isolates was very noteworthy in present study. Since less than one fifth of the isolates in present study were
ESBL producer, it seems that apart from beta-lactamases,other resistance mechanisms such as efflux pumps
and impermeability of the cell membrane may be responsible for this situation.
As resistance factors are located on mobile elements, identification and detection of strains producing these
enzymes is important in preventing of the expansion of these isolates
Type of Study:
Original Research Article |
Subject:
Antibiotic Resistance Received: 2013/11/17 | Accepted: 2013/11/21 | ePublished: 2013/11/21