Extended-spectrum beta-lactamase phenotype in Klebsiella pneumoniae isolates from Meta Department hospitals, Colombia, 2018–2022: A retrospective analytical cross-sectional study

Abstract

Background Antimicrobial resistance (AMR) is a major global health concern. Klebsiella pneumoniae is a key pathogen in healthcare-associated infections due to the production of extended-spectrum beta-lactamases (ESBLs), which limit therapeutic options. Objective To estimate the prevalence and identify factors associated with the presumptive ESBL phenotype in K. pneumoniae isolates from hospitals in the Meta Department, Colombia, between 2018 and 2022. Methods We conducted a retrospective analytical cross-sectional study using 4,808 non-carbapenem-resistant K. pneumoniae isolates obtained from routine microbiological surveillance. Bivariate analyses (Chi-square and Mann–Whitney U tests) and multivariable logistic regression were performed to evaluate associations between ESBL production and demographic, clinical, and institutional variables. Results A total of 4,808 non-carbapenem-resistant Klebsiella pneumoniae isolates were included after applying exclusion criteria. The overall prevalence of the presumptive ESBL phenotype was 22.9% (n = 1,100). In bivariate analysis, ESBL phenotype was significantly associated with male sex, older age, inpatient care, hospital type, and specimen type, particularly urine and blood samples. In multivariable analysis, male sex, inpatient status, and urine specimens remained independently associated, along with variability across specific hospitals, indicating the influence of institutional factors. The model showed limited discriminative ability (AUC = 0.62) and low explanatory power (pseudo-R² 0.03–0.05). Conclusions The presumptive ESBL phenotype in Klebsiella pneumoniae is highly prevalent and increasing over time. Its association with demographic, clinical, and institutional factors highlights the multifactorial nature of antimicrobial resistance and supports the need for strengthened surveillance and targeted antimicrobial stewardship strategies.