Antimicrobial resistance, ESBLs and Carbapenemase producing E. Coli and Klebsiella pneumoniae isolated from positive blood culture samples in Tertiary Care Hospitals Delhi NCR

Author

Narayan Ahirwar, Dr. Asgar Khan


Abstract

 Bacterial antimicrobial resistance (AMR), which arises when changes in bacteria make the drugs used to treat infections less effective, has become one of the major public health threats of the 21st century. Strains of Enterobacteriaceae that produce extended spectrum beta-(β)-lactamase (ESBL) have now become a significant issue among hospitalized patients. Since the 1980s, a dramatic rise in the number of β-lactamases has been reported of the last century, but this rise is attributable almost entirely to class A and D β-lactamases. Among the class A β-lactamases, the extended-spectrum β-lactamases (ESBLs), which can hydrolyze expanded-spectrum cephalosporins (such as cefotaxime, ceftriaxone, cefatazidime, or cefepime) and monobactams (aztreonam), constitute a public health concern. Class A ESBLs primarily comprise TEM, SHV, CTX-M, VEB, and GES enzymes. Of these, the largest number of variants reported in recent years belongs to the CTX-M. This explosive spread of CTX-Ms across the globe has been termed the “CTX-M pandemic” because of their growing description worldwide. Although various updates on CTX-M β-lactamases have been published, new information regarding the dispersion and clonality of CTX-M producing isolates, molecular epidemiology, protein plasticity, evolution and origin of the blaCTX-M genes, the influence of antibiotic use, and patients risk factors, justify this new review. Carbapenems are a class of antibiotics frequently reserved as a last-resort treatment for multidrug-resistant (MDR) Gram-negative bacterial infections. The carbapenemase genes that are reported most often consist of blaNDM-1, blaVIM, blaIMP, bla OXA-48, bla OXA-181, and bla KPC. This is a retrospective, a cohort study involving patients with bacterial bloodstream infection who were admitted to our multi centre tertiary care hospitals Delhi- NCR from January 1, 2023, through December 31, 2025. A total of 41,871 samples were collected during the study period, of which 5,858 (14.0%) were culture positive samples. Escherichia coli was the most frequently isolated organism, accounting for 3,356 cases (57.28%). Klebsiella pneumoniae was the isolated. Resistance was highest to cefuroxime/cefuroxime axetil (89.85%), followed by ceftriaxone (88.59%), nalidixic acid (84.82%), ciprofloxacin (83.52%), and levofloxacin (78.91%).



Keywords

ESBL, Carbapenemase, Antimicrobial Resistant, Blood culture samples



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References


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