Introduction:

Infections caused by bacteria resistant to multiple antibiotics are a worldwide problem. The objective of this research was to determine the antimicrobial resistance profile of Escherichia coli and Klebsiella pneumoniae in patients who attended the Hospital del Norte, Cochabamba, Bolivia. Method: The population consisted of 134 patients. Samples of urine, sputum, catheter tip, tracheal aspirate, vaginal secretion, abdominal fluid, abscess, pharyngeal secretion, and scrotal secretion were included, coming from patients of both sexes who were attended between the months of December 2022 and April 2023. Isolation and identification of bacteria were carried out in Agar, blood, Mac Conkey, Eosin Methylene Blue (EMB), biochemical tests and determination of antibiotic resistance and sensitivity in vitro using the agar diffusion disk method. Results: The microorganisms that were isolated with the highest prevalence were Escherichia coli with 93.3%, followed by Klebsiella pneumoniae with 6.7%. Both microorganisms presented extended-spectrum beta-lactamase (ESBL), extended-spectrum beta-lactamase (ESBL) and serine-beta-lactamase (cAMP) resistance mechanisms. Conclusion: The most isolated bacterium was Escherichia coli, which produced ESBL, ESBL and cAMP, more frequently in females. Presenting multi-resistance to the antibiotics cefazolin, nalidixic acid, ciprofloxacin, ampicillin and gentamicin. And K. pneumoniae presented multiresistance to cefazolin, ciprofloxacin, ampicillin, cefotaxime and gentamicin.