Liofilchem™ MTS™ Imipenem/Imipenem+EDTA IMI/IMD 4-256/1-64, MIC Test strips

The Liofilchem™ MTS™ Imipenem/Imipenem+EDTA MIC Test Strips (IMI/IMD) are advanced diagnostic tools designed for the phenotypic detection of metallo-β-lactamases (MBLs) in Gram-negative bacteria. These dual-gradient MIC strips enable the accurate determination of minimum inhibitory concentrations (MICs) for imipenem alone and imipenem combined with EDTA, a chelating agent that inhibits MBL activity. They are highly effective for identifying resistance mechanisms and guiding antimicrobial therapy.

Key Features

1. Dual-Component MIC Testing:
   • Imipenem: Evaluates baseline carbapenem susceptibility.
   • Imipenem+EDTA: Differentiates MBL-mediated resistance by observing EDTA's inhibitory effects.
2. Broad MIC Range:
   • Imipenem: 4–256 µg/mL.
   • EDTA synergy: 1–64 µg/mL.
3. Targeted Pathogen Coverage:
   • Designed for use on Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii.
4. Standardized Testing:
   • Complies with CLSI and EUCAST guidelines for carbapenem resistance testing.
5. Enhanced Sensitivity:
   • Detects low-level MBL activity not identifiable through standard phenotypic methods.

Applications

• Detection of Metallo-β-Lactamases (MBLs): Includes NDM, VIM, and IMP types.
• Differentiation of Resistance Mechanisms: Differentiates MBLs from serine β-lactamases or efflux pumps.
• Surveillance Programs: Supports antimicrobial resistance (AMR) monitoring efforts.
• Treatment Guidance: Provides data for informed antimicrobial therapy decisions.

Test Procedure

1. Sample Preparation

• Prepare a bacterial suspension equivalent to 0.5 McFarland standard.
• Inoculate a Mueller-Hinton Agar plate evenly with a sterile swab.

2. Strip Placement

• Apply the Imipenem/Imipenem+EDTA MIC strip on the inoculated plate, ensuring proper adherence to the agar surface.

3. Incubation

• Incubate the plate at 35–37°C for 16–20 hours under aerobic conditions.

4. MIC Interpretation

• Read the MICs at the point of complete inhibition where the ellipse intersects the strip.
• Calculate the difference between the MICs of imipenem (IMI) and imipenem+EDTA (IMD):
  • MIC reduction ≥ 3 dilutions (8-fold) indicates MBL production.

Results Interpretation

Control Data

Technical Specifications

Advantages

Comparison with Other Methods

Reference Data

1. CLSI M100 Guidelines: MIC breakpoints and interpretive criteria.
2. EUCAST Recommendations: International standards for MIC testing.
3. Scientific Studies:
   • “Phenotypic Detection of Metallo-β-Lactamases Using Imipenem-EDTA MIC Gradient Strips,” Journal of Clinical Microbiology.
   • “Comparison of Gradient Diffusion and Molecular Methods for Carbapenemase Detection,” Antimicrobial Agents and Chemotherapy.

Conclusion

The Liofilchem™ MTS™ Imipenem/Imipenem+EDTA (IMI/IMD) 4-256/1-64 MIC Test Strips offer a robust, reliable, and sensitive method for detecting metallo-β-lactamases in Gram-negative bacteria. By adhering to international standards and providing accurate phenotypic results, these strips are indispensable tools in clinical microbiology for combating antimicrobial resistance.