Objective:to identify possible risk factors for acquisition of Enterobacterial strains with a marker for resistance to carbapenems. Methods:exploratory case-control study performed in hospital settings. The study sample consisted of patients with biological specimens that tested positive for carbapenem-resistant Enterobacteriaceae (cases), with the disk diffusion test and Etest, and controls with biological samples testing negative for carbapenem-resistant Enterobacteriaceae. In all, 65 patients were included: 13 (20%) cases and 52 (80%) controls. Results:the microorganisms isolated were Serratia marcescens (6), Klebsiella pneumoniae (4), and Enterobacter cloacae (3). Univariate analysis revealed that length of hospitalization prior to sample collection (p=0.002) and having a surgical procedure (p=0.006) were statistically significant. In the multivariable logistic regression model, both were still significant, with odds ratios of 0.93 (p = 0.009; 95% CI: 0.89 to 0.98) for length of hospitalization prior to sample collection, and 9.28 (p = 0.05; 95% CI: 1.01 to 85.14) for having a surgical procedure. Conclusion:shorter hospitalization times and increased surveillance of patients undergoing surgery could play a decisive role in reducing the spread of carbapenem-resistant microorganisms in hospital settings.