Genomic Analysis of Highly Virulent blaCTX-M, blaSHV and blaTEM Genes in Resistant Strains of E.coli and Klebsiella: an emerging threat
Mehwish Saleem, Farzana Rashid, Mariam Faiz
186
ABSTRACT
Background: The term antimicrobial resistance refers to the ability to resists the
effects of drugs formally used to treat them and this term relates only to
bacteria becoming resistant. Microorganisms that are resistant to multiple
drugs are known as multidrug-resistant bacteria.
Aim: To
investigate the prevalence of SHV, TEM and CTXm
genes from E.coli and Klebsiella isolated from patients of
Lahore, Pakistan.
Methods: Patients with prolonged hospital stay
were enrolled in this cross-sectional study with 60 samples comprising Klebsiella pneumoniae and Escherichia coli (Ctx, Cro, Caz
resistant) were identified in clinical specimens. To assess susceptibility, the
disc diffusion method was applied with eight antibiotic panel of cephalosporin
3rd generation. A Double disc, combined disc test was used to
identify the ESBL-producing bacteria. By real - time PCR, The presence of the
genes encoding blaTEM, blaSHV, and blaCTXm was tested in ESBL positive isolates
as well as additional isolates with MICs of less than 4g/mL for ceftazidime,
cefotaxime, ceftriaxone, and aztreonam (PCR).
Results: The
frequency of E. coli and Klebsiella bacteria was found in 59% and
41% of the 60 samples, respectively. According to the data, 23 isolates
(16.37%) were multidrug resistant, and 7(6.89%) were ESBL-positive. At least
one of the antibiotics ceftazidime, ceftriaxone, or cefotaxime was resistant to
30(25.86%) of the isolates. The ESBL genes were sequenced to corroborate the
PCR result.
Conclusions:
Among E. coli and Klebsiella bacteria obtained from
patients, blaTEM-116 was the most frequently isolated ESBL gene, followed by
Shv and Ctxm.
Keywords: Antibiotic Resistance, Beta- Lactamases, E. coli, Klebsiella
pneumonia
ABSTRACT
Background: The term antimicrobial resistance refers to the ability to resists the
effects of drugs formally used to treat them and this term relates only to
bacteria becoming resistant. Microorganisms that are resistant to multiple
drugs are known as multidrug-resistant bacteria.
Aim: To
investigate the prevalence of SHV, TEM and CTXm
genes from E.coli and Klebsiella isolated from patients of
Lahore, Pakistan.
Methods: Patients with prolonged hospital stay
were enrolled in this cross-sectional study with 60 samples comprising Klebsiella pneumoniae and Escherichia coli (Ctx, Cro, Caz
resistant) were identified in clinical specimens. To assess susceptibility, the
disc diffusion method was applied with eight antibiotic panel of cephalosporin
3rd generation. A Double disc, combined disc test was used to
identify the ESBL-producing bacteria. By real - time PCR, The presence of the
genes encoding blaTEM, blaSHV, and blaCTXm was tested in ESBL positive isolates
as well as additional isolates with MICs of less than 4g/mL for ceftazidime,
cefotaxime, ceftriaxone, and aztreonam (PCR).
Results: The
frequency of E. coli and Klebsiella bacteria was found in 59% and
41% of the 60 samples, respectively. According to the data, 23 isolates
(16.37%) were multidrug resistant, and 7(6.89%) were ESBL-positive. At least
one of the antibiotics ceftazidime, ceftriaxone, or cefotaxime was resistant to
30(25.86%) of the isolates. The ESBL genes were sequenced to corroborate the
PCR result.
Conclusions:
Among E. coli and Klebsiella bacteria obtained from
patients, blaTEM-116 was the most frequently isolated ESBL gene, followed by
Shv and Ctxm.
Keywords: Antibiotic Resistance, Beta- Lactamases, E. coli, Klebsiella
pneumonia