CARACTERIZACIÓN FENOTÍPICAS DE BETALACTAMASAS DE TIPO AMPC EN ESCHERICHIA COLI AISLADAS EN INFECCIONES DEL TRACTO URINARIO EN PACIENTES DEL LABORATORIO CLÍNICO BACTERIOLÓGICO MEDIN–LAB

Abstract

AmpC-type beta-lactamases, enzymes that confer resistance to a variety of β-lactam antibiotics, have shown an increase in prevalence, particularly in pathogens responsible for urinary tract infections (UTIs), such as Escherichia coli. Antimicrobial resistance poses a significant threat to global public health, as it complicates the treatment of common infections and increases the risk of disease spread. The rising resistance of bacteria to antibiotic treatments is associated not only with clinical challenges but also with considerable social and economic consequences. Limiting the spread of resistant microorganisms and reducing associated morbidity is crucial to preserving the effectiveness of antibiotics and preventing public health crises. Research has primarily focused on extended-spectrum beta-lactamases, complicating the establishment of routine reporting protocols in clinical laboratories, making it essential to consider the clinical and epidemiological significance of AmpC betalactamases. The methodology included the identification of Escherichia coli in patients with UTIs and the detection of AmpC beta-lactamases using the disk approximation method. Escherichia coli was the most frequently identified microorganism in UTIs, accounting for 47.61% of the infections in the study. Most patients were female (97.5%), and the most affected age group was 18 to 35 years (36.25%). Thirteen strains were identified as AmpC-positive (16.25%), with most affected being adult women. The positive strains showed resistance to cefoxitin (16.25%), cefotaxime (16.25%), and amoxicillin/clavulanic acid (16.25%). Additionally, the protocol developed for the phenotypic identification of AmpC betalactamases was outlined in a flowchart for laboratory application, enabling control of resistance mechanisms through phenotypic identification methods. These findings underscore the importance of considering bacterial resistance when prescribing antibiotics, especially in cases of UTIs, and highlight the need for prudent antibiotic use to combat emerging resistance.