MIC Made as Easy as A, B, C, D

MIC Made as Easy as A, B, C, D


  • Post By : Dr. Rahul G. Warke, Director Research and Development, Microbiology HiMedia Laboratories Private Limited

  • Source: Microbioz India

  • Date: 31 Aug,2020

In recent years, there has been a growing interest in researching and developing new antimicrobial agents from various sources to combat microbial resistance. Several factors led to this increase, particularly the selection pressure exerted by overuse & misuse of antimicrobial agents which resulted in the emergence of resistant microorganisms. This, in turn, led to increasing morbidity and mortality and an overall increase in healthcare costs. The dramatic decline in the development of new antibiotics or scaffolds active against these multidrug-resistant pathogens has further complicated the therapeutic dilemma. Hence in the past couple of years, a greater attention has been paid to the antimicrobial activity screening and evaluating methods. Making the antibiotic potency testing part easier and less skill development, would welcome more testing.

An important task of the clinical microbiology laboratory is the performance of antimicrobial susceptibility testing of the bacterial isolates of interest. The goals of testing are to detect possible drug resistance in common pathogens and to right drug of choice for particular infection. The most widely used testing methods include broth microdilution or rapid automated instrument methods that use commercially marketed materials and devices. Manual methods that provide flexibility and possible cost savings include the disk diffusion and gradient diffusion methods. Each method has its strengths and weaknesses, including organisms that may be accurately tested by the method. Some methods provide quantitative results (eg, minimum inhibitory concentration (MIC), and all provide qualitative assessments using the categories susceptible, intermediate, or resistant. In general, current testing methods provide accurate detection of common antimicrobial resistance mechanisms.

Disc Diffusion

Micro Broth Dilution

Agar Dilution

However, newer or emerging mechanisms of resistance require constant vigilance regarding the ability of each test method to accurately detect resistance. MIC can be helpful in establishing the level of resistance, intermediate and sensitivity of a particular bacterial strain and can substantially affect the decision to use certain antimicrobial agents.

MIC values lower than the breakpoints are interpreted as susceptible results and those higher as resistant for treatment guidance. The Clinical Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines are the most popular breakpoint guidelines used in antimicrobial susceptibility testing worldwide.

The broth dilution test is the oldest and accurate antimicrobial susceptibility testing method and involves the preparation of twofold dilutions of antibiotics in a liquid growth medium. In dilution tests, microorganisms are tested for their ability to produce visible growth in broth (broth dilution) containing dilutions of the antimicrobial agent. The lowest concentration of an antimicrobial agent (in mg/L) that, under defined In vitro conditions, prevents the appearance of visible growth of a microorganism within a defined period of time, is known as the MIC. The MIC is a guide for the clinician to the susceptibility of the organism to the antimicrobial agent and aids treatment decisions.

HiMIC™ plate is a breakthrough in MIC detection with ease and accuracy. Seven concentration on a single detachable strip covering breakpoint scale which helps in reliable interpretation for Sensitive, Intermediate and Resistance detection with easy visual inspection, in compliance with CLSI and EUCAST guidelines. It reduces overall time taken for the preparation of tedious micro broth dilution.

HiMIC™ Plate Advantages:

1.A breakthrough in the detection of MIC with ease and accuracy.

2.Easy breakp

3.Point based visual evaluation.

4.Hassel free micro broth dilution.

5.Quantitative analysis as per EUCAST and CLSI guidelines.

6.Reliable interpretation for Sensitive, Intermediate and Resistance detection.

7.7 concentrations in a single strip covering breakpoint scale.

8.12 tests per kit with detachable strips.

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