Among bacteria with high resistance to antimicrobials, the Gram-negative types, producers of extended-spectrum beta-lactamases (ESBL), have become an extensive problem for public health. ESBL-producing strains are often associated with various infections, such as pneumonia, septicemia, urinary infections, bacteremia, and meningitis. Klebsiella pneumoniae is a Gram-negative bacillus found in the normal microbiota of the human intestine. This microorganism has high rates of ESBL-producing strains that catalyze the hydrolysis of the beta-lactam ring of antimicrobials that have it. The TSDD methodology uses the synergism of the antibiotics diffused in the Muller Hinton agar (MHA) so that the appearance of the phantom area occurs. However, this synergism may present false results in case the distance between the discs containing the drugs is greater than the capacity of antimicrobial diffusion in MHA. ESBL detection is a low-cost technique that has been frequently used in microbiology laboratories because it is easy to perform and provides reliable results, though a consensus as to the standard distances between disks is nonexistent. The objective of this research is to measure how far, considering center to center, this laboratory routine can be used in the double-disc synergism test (TSDD) for phenotypic detection of ESBL. A strain of ESBL-producing K. pneumoniae ATCC ™ 700603 was used to perform this work as recommended by BrCAST. Our results indicate that the variations in distances can bring false-negative results to values ​​greater than 34 mm and smaller than 20 mm.

Author Biography

Alessandra Barrochelli da Silva Ecker, Centro Universitário Ingá
Possui Graduação em FARMÁCIA com Habilitação em ANÁLISES CLÍNICAS pela UNIVERSIDADE ESTADUAL DE MARINGÁ, UEM-PR, Especialização em Farmacologia Oncológica pelo HOSPITAL ERASTO GAERTNER, Curitiba-PR, 2012. Mestrado no programa de pós graduação de Biociências e Fisiopatologia, PBF, da Universidade Estadual de Maringá - PR, 2015. Docente nas disciplinas de Microbiologia clínica e estágio em análises clínicas para o curso de Biomedicina e Farmácia Hospitalar para o curso de Farmácia no centro Universitário Ingá - Uningá
How to Cite
OLIVEIRA, Thais Druscz de; AGUERA, Raul Gomes; ECKER, Alessandra Barrochelli da Silva. EVALUATION OF DISTANCES IN THE PHENOTYPIC DETECTION OF BETALACTAMASE OF SPECTRUM EXTENDED IN ATCCTM Klebsiella pneumoniae. Revista Uningá, [S.l.], v. 57, n. 3, p. 39-49, oct. 2020. ISSN 2318-0579. Available at: <http://revista.uninga.br/index.php/uninga/article/view/2857>. Date accessed: 18 may 2022.