| Mohammad Kargar | 2 Articles |
Objectives
The resistance of <i>Streptococcus pneumoniae</i> to the recently available antibiotic treatment has been a growing problem. The aim of the study was to determine the quinolone-resistant strains and detect the presence of mutations in the quinolone resistance-determining regions of the <i>gyrA</i>, <i>parE</i>, and <i>parC</i> genes. Methods In this study, for the first time in Iran, the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was used to investigate the presence of mutations at quinolone resistance-determining regions of topoisomerase IV and DNA gyrase on 82 <i>S. pneumoniae</i> strains, among them 45 clinical samples were from patients and 37 from healthy carriers (control group). Results In clinical samples, 34 (75.56%) strains contained mutations in the <i>parC</i> gene, 31 (68.89%) carried mutations in the <i>gyrA</i> gene, and 14 (31.11%) had <i>parE</i> gene mutations. Antibiotic susceptibility test was performed using the CLSI (Clinical and Laboratory Standards Institute) criteria on three different generations of quinolone family, with nalidixic acid (82.22%) showing the highest resistance and levofloxacin (42.22%) the least resistance. Conclusion Results indicated that there is a significant correlation between quinolone resistance development and mutations in the <i>parE</i> gene as well as in the <i>parC</i> and <i>gyrA</i> genes. Citations
Citations to this article as recorded by
Objectives
Horizontal transfer of integrons is one of the important factors that can contribute to the occurrence of multidrug-resistant (MDR) bacteria. This study aimed to determine the prevalence of integrons among MDR <i>Escherichia coli</i> strains isolated from stool specimens and investigate the associations between the existence of integrons and MDR properties in the southwest of Iran. Methods There were 164 <i>E. coli</i> strains isolated from January 2012 to June 2012. Fecal specimens identified as <i>E. coli</i> by the conventional methods. Subsequently the antibiotic resistance was assessed using Clinical and Laboratory Standard Institute criteria. The presence of class 1–3 integrons and embedded gene cassettes was verified using specific primers by multiplex polymerase chain reaction assay. Results Among a total of 164 studied samples, 69 (42.07%) isolates were multidrug resistant. Class 1 and class 2 integrons were present in 78.26% and 76.81% MDR isolates, respectively. For the first time in Iran, class 3 integron was observed in 26.09% MDR isolates. Significant correlations were identified between: class 1 integron and resistance to amikacin, gentamicin, chloramphenicol, ampicillin, tetracycline, nalidixic acid, and co-trimoxazole; class 2 integron and resistance to aminoglycosides, co-trimoxazole, cefalexin, ampicillin, and chloramphenicol; and class 3 integron and resistance to gentamicin, kanamycin, and streptomycin. Conclusion Our results indicate that integrons are common among MDR isolates and they can be used as a marker for the identification of MDR isolates. Therefore, due to the possibility of a widespread outbreak of MDR isolates, molecular surveillance and sequencing of the integrons in other parts of the country is recommended. Citations
Citations to this article as recorded by
|
|
