Antibiotic Susceptibility Patterns for Carbapenem-Resistant Enterobacteriaceae

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Carbapenem resistance (CR) in Enterobacteriaceae is a growing global health concern.
• Carbapenem-resistant Enterobacteriaceae (CRE) are associated with high mortality rates.
• Urgent need for effective therapeutic options against CRE infections.

Purpose of the Study:

• To determine the antibiotic susceptibility patterns of carbapenem-resistant Enterobacteriaceae (CRE) to various antibiotics.
• To evaluate the efficacy of new and old antibiotics against prevalent CRE species in Iran.
• To identify potential treatment strategies for CRE infections.

Main Methods:

• Collection of bacterial isolates (Klebsiella pneumoniae, E. coli, Enterobacter spp.) from 10 Iranian hospitals over one year.
• Identification of CRE based on resistance to meropenem and/or imipenem.
• Antibiotic susceptibility testing using disk diffusion and MIC methods for fosfomycin, rifampin, metronidazole, tigecycline, aztreonam, and colistin.

Main Results:

• Prevalence of CRE was 4.4% for E. coli, 12% for K. pneumoniae, and 8.2% for Enterobacter spp.
• All CRE strains exhibited resistance to metronidazole and rifampicin.
• Tigecycline showed the highest sensitivity rate against CRE strains, followed by levofloxacin for Enterobacter spp.

Conclusions:

• Tigecycline is a promising therapeutic option for treating infections caused by carbapenem-resistant Enterobacteriaceae.
• Clinicians should consider tigecycline for CRE infections based on its demonstrated effectiveness.
• Continued surveillance of antibiotic resistance patterns is crucial for guiding treatment decisions.