Related Experiment Video

Updated: Jun 24, 2026

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli
06:56

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli

Published on: March 24, 2023

Risk factors and clinical features of infections caused by plasmid-mediated AmpC beta-lactamase-producing

Yoon Soo Park1, Sunmi Yoo, Mi-Ran Seo

  • 1Department of Internal Medicine, Gachon University, Gil Medical Center, 1198 Guwol-dong, Namdong-gu, Incheon 405-760, South Korea.

International Journal of Antimicrobial Agents
|March 20, 2009
PubMed

Insights

Infections by plasmid-mediated AmpC beta-lactamase (plasmid AmpC)-producing Enterobacteriaceae are linked to increased treatment failure. Prior use of oxyimino-cephalosporins is a significant risk factor for these infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Clinical Pharmacy

Background:

  • Plasmid-mediated AmpC beta-lactamases (plasmid AmpC) are increasingly recognized in Enterobacteriaceae.
  • Understanding risk factors and clinical features of plasmid AmpC-producing Enterobacteriaceae infections is crucial for effective management.

Purpose of the Study:

  • To analyze risk factors and clinical features of infections caused by plasmid AmpC-producing Enterobacteriaceae.
  • To identify independent risk factors for infection and treatment failure.

Main Methods:

  • A case-control study was conducted in two tertiary care hospitals.
  • Patients infected with plasmid AmpC-producing Enterobacteriaceae were prospectively recruited.
  • Plasmid AmpC enzymes were characterized using isoelectric focusing, enzyme inhibition assays, and polymerase chain reaction.

Main Results:

  • Twenty Klebsiella pneumoniae and ten Escherichia coli isolates were analyzed.
  • CMY-2 and DHA-1 were the most common plasmid AmpC types.
  • Prior oxyimino-cephalosporin use (aOR, 10.8) and urinary catheter use (aOR, 6) were risk factors for infection.
  • Infection with plasmid AmpC-producing Enterobacteriaceae was an independent risk factor for treatment failure at 72 hours (aOR, 9.78).

Conclusions:

  • Infections caused by plasmid AmpC-producing Enterobacteriaceae significantly increase the risk of treatment failure.
  • Prior use of oxyimino-cephalosporins is a significant risk factor for acquiring these infections.

More Related Videos

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes08:58

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes

Published on: March 3, 2023

Related Concept Videos

Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Bacterial Gastroenteritis01:18

Bacterial Gastroenteritis

Bacterial gastroenteritis, characterized by diarrhea, abdominal cramps, and vomiting, is often caused by ingestion of contaminated food or water and is frequently associated with pathogenic Escherichia coli strains. These microbes exploit two principal mechanisms to inflict disease.Shiga toxin–producing E. coli, also referred to as STEC—notably O157:H7—release Shiga toxins that target ribosomes, blocking protein synthesis. The B subunit of the toxin binds the host glycolipid receptor...
Determinants of Bacterial Pathogenicity and Virulence01:20

Determinants of Bacterial Pathogenicity and Virulence

Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
Atypical Pneumonia01:14

Atypical Pneumonia

Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...
Pneumonia I: Introduction01:29

Pneumonia I: Introduction

Pneumonia is an infection of the lower respiratory tract that leads to inflammation of the lung parenchyma, often resulting in the accumulation of inflammatory exudate in the alveoli and airways. Unlike the watery, low-protein fluid exudate in pulmonary edema, the exudate in this case is a thick fluid rich in immune cells, proteins, and debris produced during infection and inflammation.This impairs gas exchange and can lead to consolidation of lung tissue. The infection may be caused by a...