Molecular Characterization of Klebsiella pneumoniae Clinical Isolates with Elevated Resistance to Carbapenems

نویسندگان

  • Rasha Barwa
  • Mona Shaaban
چکیده

BACKGROUND Emergence of carbapenems-resistant K. pneumoniae represents a serious challenge for antimicrobial therapy. OBJECTIVE The aim of this research is to determine different mechanisms mediating the emergence of K. pneumoniae isolates with high-level carbapenem resistance. METHOD A total of 80 K. pneumoniae isolates were purified from sputum and urine specimens. The minimum inhibitory concentrations (MICs) of imipenem and meropenem were determined by broth microdilution method. Carbapenemases were detected by Modified Hodge test and PCR. Additionally, the copy numbers of the identified genes (blaVIM-1, blaNDM-1 and blaOXA-48) were quantified by RT-PCR. The outer membrane proteins OmpK35 and OmpK36 of the resistant isolates were analyzed. RESULTS Eight isolates were resistant to carbapenems; six of these isolates possessed elevated MICs to imipenem and meropenem (≥16 µg/ml). Carbapenem resistant isolates harbored blaNDM-1 (n=5), blaVIM-1 (n=4) and blaOXA-48 (n=1) with some isolates had multiple carbapenemases genes. Six isolates with high MICs to imipenem contained multi-copies of the carbapenemases genes along with the lack of OmpK35. Isolates with intermediate resistance to carbapenems (MIC; 4-8 µg/ml) did not exhibit multiple carbapenemases but lacked the OmpK35. Random amplified polymorphic DNA exhibited three different patterns and indicated that five isolates encoded the same pattern P1. CONCLUSION This study elucidated that multiple carbapenemases genes, high copy number of carbapenemases and loss of the porin OmpK35 could collectively contribute to the emergence of K. pneumoniae isolates with high resistance to carbapenems. Hence, more restrictions should be applied on the use of carbapenems to reduce the emergence of the resistant clones.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Investigating the Resistance of Klebsiella Pneumoniae Clinical Isolates Producing Carbapenemase and ESBL Enzymes to Colistin and Fosfomycin Antibiotics

 Introduction: A Klebsiella pneumoniae bacterium, which is the most important species of the Klebsiella genus, mainly causes hospital infections. Moreover, it has a high resistance to most of the available antibiotics, which has caused concern among doctors all over the world. Therefore, the amount of antibiotic resistance and the effect of these antibiotics on Klebsiella pneumoniae isolates pr...

متن کامل

Evaluation of Resistance to Fluoroquinolones and Its Relationship whit parC Gene Mutation in Klebsiella pneumoniae Clinical Isolates

Background & Objective: Klebsiella pneumoniae has received attention due to a wide range of diseases and antibiotic resistance.The resistance to fluoroquinolones in gram-negative bacteria is often due to chromosomal mutations in the gyr and par genes. This research aimed at investigating the pattern of fluoroquinolone resistance and its relation with a mutation in the parC gene among clinical i...

متن کامل

MOLECULAR TYPING AND INVESTIGATING THE PRESENCE OF EFFLUX GENES IN URINARY ISOLATES OF KLEBSIELLA PNEUMONIAE

Background & Aims: The efflux pumps play an important role in the development of drug resistance in Klebsiella pneumoniae. The aim of this study was to investigate the antibiotic resistance, and the presence of efflux genes, as well as molecular typing in clinical isolates of Klebsiella pneumoniae. Materials & Methods: In this cross sectional descriptive study, a total of 100 K. pneumoniae iso...

متن کامل

شناسایی ایزوله ‌های کلبسیلا پنومونیه دارای ژن blaCTX و تعیین مقاومت متقاطع آنها در بیماران بستری در بیمارستان

Background and Aim: Klebsiella pneumoniae is a member of the Enterobacteriaceae family. There is a global emergence of multidrug-resistant (MDR) strains of K. pneumoniae, a Gram-negative enteric bacterium that causes nosocomial and urinary tract infections. The aims of the present study were to identify the Klebsiella pneumoniae infections in hospitalized patients, characterization of blaCTX ge...

متن کامل

Genome Sequences of Five Clinical Isolates of Klebsiella pneumoniae

Klebsiella pneumoniae is a nosocomial pathogen of emerging importance and displays resistance to broad-spectrum antibiotics, such as carbapenems. Here, we report the genome sequences of five clinical K. pneumoniae isolates, four of which are carbapenem resistant. Carbapenem resistance is conferred by hydrolyzing class A β-lactamases found adjacent to transposases.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 11  شماره 

صفحات  -

تاریخ انتشار 2017