Performance evaluation of antibiotic-supplemented agar plates in the detection of multidrug-resistant bacteria

Abstract

Objective: To evaluate the performance of agar plates supplemented with antibiotics in the detection of multidrug-resistant bacteria, in order to use this method in microbiological surveillance cultures. Methods: 160 samples of bacterial colonies were selected, containing gram-positive cocci and gram-negative rods, fermenting and non-fermenting, sensitive and multiresistant to antimicrobials, which were seeded in the culture media supplemented with antibiotics and later the presence or absence was evaluated of bacterial growth. Results: The growth of all multidrug-resistant microorganisms on the supplemented agar plates and the absence of growth of antimicrobial-sensitive microorganisms were evidenced, but with less detection time and less cost per analysis. Conclusion: The method under study showed 100% agreement with the previously used reference method. Considering its excellent performance, associated with reduced detection time and reduced cost of the approach, it presents itself as an important solution for use in microbiological surveillance cultures.