فهرست مطالب zahra tahanasab

Extended‑spectrum β‑lactamase (ESBL)‑producing is a significant resistant mechanism to β‑lactams in Enterobacteriaceae, especially in Klebsiella pneumoniae. The main objectives of this study were to genetically characterize urinary clinical isolates of K. pneumoniae through the investigating of blaTEM, blaCTX‑M and using molecular typing by Enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC‑PCR) method. We also determined the frequency of antibiotic resistance of K. pneumoniae strains to characterize the β‑lactamases included.

A cross‑sectional study was carried out to evaluate 98 strains of K. pneumoniae isolated from urine culture of outpatients referred to Al‑Zahra Hospital, Isfahan, Iran. Antibiotic susceptibility testing was performed using Kirby–Bauer’s method. Screening of ESBLs was carried out using double‑disk screening test. PCR technique was performed to detect TEM and CTX‑M genes. The total DNA of each strain was tested by ERIC‑PCR.

In 98 K. pneumoniae studied clinical isolates, 25.5% were ESBL producing and 44.9% multidrug‑resistant (MDR). From 25 ESBL isolates, 23 (92%) cases showed MDR phenotype. In ESBL producing isolates, 23 (92%) were blaCTX‑M and 19 (76%) blaTEM positive. The antimicrobial drug susceptibilities of ESBL isolates indicated high resistant rates for cefotaxime and ceftazidime. All 25 ESBL producing isolates were resistant to cefotaxime. Complex patterns of fingerprints isolates showed that 36% of the isolates were belonged to the cluster no 5.

This study revealed high antimicrobial resistance rates among ESBL isolates which can lead to various health difficulties. Epidemiological data collection from patients is recommended to develop the strategies to manage antibiotic resistance.

Urinary tract infection (UTI) is one of the most frequent infectious diseases and can occur in all age groups. Due to various complications of urinary tract infections, timely and proper treatment seems important. This study aimed to assess the antibiotic resistant pattern in Escherichia coli derived from outpatients and inpatients with urinary tract infections in Alzahra Hospital, Isfahan, Iran
135 isolates of Escherichia coli (from urine) were collected from September to February, 2013, from Alzahra Hospital (Isfahan, Iran). The samples were cultured on nutrient agar, Mac Conkey agar, Blood agar and Eosin methylene blue (EMB) agar. Bacterial susceptibility to antimicrobial agents was determined using Kirby-Bauer disk diffusion method as recommended by the Clinical and Laboratory Standards Institute (CLSI) guidelines.
Findings: Among 135 Escherichia coli isolates, 91 isolates belonged to outpatients and 44 to inpatients. In total, 68% of the participants were women. Antibiotic resistance to ampicillin, ceftazidime, nalidixic acid and trimethoprim/sulfamethoxazole were higher than 50%. The rates of resistance to ceftazidime, ampicillin, trimethoprim/sulfamethoxazole, cefepime, and cefotaxime in outpatients were higher than in inpatients.
Due to excessive use of antibiotics and increasing antibiotic resistance, it is necessary to perform antibiotic resistance tests routinely in laboratories.

This study was to evaluate the prevalence of CTX-Mand TEM type ESBLs-producing K. pneumoniae and determination of MDR, XDR, and PDR phenotypes of these isolates as well as find out the genetic relationship and molecular typing of these isolates using phenotypic and genotypic methods.
Non-repetitive 96 K. pneumonia isolates were isolated from hospitalized patients in Al-Zahra hospital of Isfahan, Iran. The antibiotic susceptibility test was assessed for 20 antibiotics using Kirby-Bauer disk diffusion method. The frequency of ESBL-producing isolates was determined by phenotypic confirmatory test. All ESBLs-producing isolates were assessed for blaTEM and blaCTX-M genes using PCR method. Molecular typing was performed by enterobacterial repetitive intergenic consensus sequence-based PCR (ERIC-PCR).
Among 96 isolates, 58 isolates (60.4%) were ESBL-producers. In this study, 85.7% and 30.3% of ESBL-producing isolates showed MDR and XDR phenotypes, respectively. No PDR isolate was found. PCR amplification on ESBL-producing isolates showed that 47 (81%) isolates were carried blaTEM gene, while blaCTX-M was detected in all isolates (100%). ERIC-PCR typing was characterized the high genetic similarity among ESBL-producing K. pneumonia isolates and revealed 32 band pattern for the isolates.
This study showed high prevalence of important ESBL genes (blaCTX-M and blaTEM genes) among the K. pneumoniae isolated from in-patients. Constant following of ESBLs, also identification of their types, in bacteria isolated from hospitalized patients has an important clinical impact. It can provide valuable information for the choice of appropriate antibacterial therapy and decrease of antibiotic resistance.