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Rapid and Specific Detection of Acinetobacter baumannii Infections Using a Recombinase Polymerase Amplification/Cas12a-based System
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Rapid and Specific Detection of Acinetobacter baumannii Infections Using a Recombinase Polymerase Amplification/Cas12a-based System

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Epidemic multidrug-resistant Acinetobacter baumannii related to European clonal types I and II in Rome (Italy)

S D'Arezzo1, A Capone, N Petrosillo

  • 1National Institute for Infectious Diseases Lazzaro Spallanzani, I.R.C.C.S., Rome, Italy.

Clinical Microbiology and Infection : the Official Publication of the European Society of Clinical Microbiology and Infectious Diseases
|May 12, 2009
PubMed

Insights

Two main clones of multidrug-resistant Acinetobacter baumannii, linked to European epidemic strains, dominated intensive care units in Rome. Clone type 1, carrying carbapenem resistance genes, showed significant hospital spread potential.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Molecular Epidemiology

Background:

  • Acinetobacter baumannii is a significant cause of hospital-acquired infections, particularly in intensive care units (ICUs).
  • Multidrug resistance (MDR) in A. baumannii poses a major therapeutic challenge.
  • Understanding the molecular epidemiology of MDR strains is crucial for infection control.

Purpose of the Study:

  • To investigate the molecular epidemiology of MDR Acinetobacter baumannii strains in Roman ICUs.
  • To identify the genetic basis of antibiotic resistance in these isolates.
  • To assess the clonal relationships and spread of epidemic strains.

Main Methods:

  • Isolation and characterization of 88 MDR A. baumannii strains from ICU patients.
  • Molecular typing using Random Amplified Polymorphic DNA (RAPD) and macrorestriction analysis.
  • Detection and characterization of integrons and antibiotic resistance genes (e.g., blaOXA-58).

Main Results:

  • Two predominant clonal types, related to European epidemic clones I and II, accounted for 98.9% of isolates.
  • Type 1 clone was found in all surveyed ICUs, indicating widespread presence.
  • Carbapenem resistance in type 1 isolates was linked to the blaOXA-58 gene; class 1 integrons were detected in both types.

Conclusions:

  • The A. baumannii type 1 clone, associated with European epidemic strains, demonstrates a high potential for inter-hospital spread.
  • Genetic elements like integrons and specific resistance genes contribute to the MDR phenotype.
  • Effective infection control strategies are needed to manage the spread of these epidemic clones.

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