All carbapenem-resistant Gram-negative bacterial isolates obtained in the Costa Rican National Network of Bacteriology Laboratories are routinely referred to the National Reference Center for Bacteriology for national-laboratory for surveillance and characterization of their carbapenem-related-mechanism of resistance. As a result of this healthcare-associated infection surveillance, two bacterial isolates with unknown mechanisms for carbapenem resistance were investigated. The isolates were subjected to taxonomic identification, antimicrobial susceptibility testing, whole-genome characterization, using Illumina and Oxford Nanopore technologies, and bioinformatic analyses. The isolates were identified as Enterobacter roggenkampii and Enterobacter sichuanensis. While the isolates presented different antimicrobial resistance profiles, both were resistant to carbapenems, positive for the modified carbapenem inactivation method (mCIM), and showed inhibition of carbapenem resistance with boronic acid. The full characterization of the isolates' genomes, revealed the presence of the rare chromosomal blaIMI-4 gene inserted within 25-kb integrative mobile elements, closely related to EcloIMEX-2. The limited global distribution of the blaIMI-4 variant, along with its identification in two distinct bacterial species in Costa Rica within integrative mobile elements, underscores the critical need for regular antibiotic resistance surveillance using next-generation sequencing technologies. This study demonstrates that this practice allows timely detection of novel or rare mechanisms of antibiotic resistance.

Objetivo: Describir y caracterizar la microbiología de las osteomielitis de pie diabético en pacientes hospitalizados en el Hospital San Juan de Dios en el año 2018. Métodos: Se consultó la base de datos local de pacientes de la Unidad de Pie Diabético para obtener los datos demográficos de los pacientes hospitalizados con diagnóstico de osteomielitis además del sistema de información de la división de Microbiología del Laboratorio Clínico con el fin de obtener los datos de especies bacterianas y sus perfiles de susceptibilidad a los antimicrobianos aisladas de las respectivas muestras de hueso. Con estos datos se construyó una base de datos para el proyecto y el análisis estadístico descriptivo se realizó en hojas de cálculo de Excel. Resultados: Enterococcus faecalis fue el agente más frecuentemente aislado (21%), seguido de Staphylococcus aureus (14%), de los cuales 70% presentó fenotipo de meticilino resistencia y Escherichia coli como tercer lugar (11%). Otros bacilos Gram negativos ocuparon un cuarto lugar, con Enterobacter cloacae (8%) y Klebsiella pneumoniae (8%) como las principales especies aisladas; cabe destacar que se evidenció la presencia de 24% de cepas portadoras de β-lactamasas de espectro extendido, con K. pneumoniae como la principal especie portadora de este fenotipo de resistencia. Conclusiones: Se reportó por primera vez a E. faecalis como la bacteria más aislada en OPD, lo cual permite concluir que la microbiología de estos cuadros en Costa Rica difiere a lo reportado en la literatura internacional y es necesario actualizar a la comunidad médica costarricense. Además, es importante destacar que a pesar de que el porcentaje obtenido de bacilos Gram negativos portadores de BLEE es inferior a lo reportado en la literatura, el 100% de las cepas de K. pneumoniae fueron portadoras de este fenotipo de resistencia, por lo tanto, es posible considerar a nivel local que el hallazgo preliminar de esta especie debería modificar el espectro terapéutico a utilizar en espera de reportes de PSA.

Background: Antimicrobial consumption (AMC) data in Latin America are scarce and usually spread out across different sources used to make AMC calculations, making it difficult to both standardize and compare regions through similar time frames. The main objective was to analyze AMC trends in Social Security tertiary care hospitals in Costa Rica in the period spanning January 2017 to December 2021, using both the defined daily dose (DDD)/100 bed days and DDD/100 discharges. Methods: This is a retrospective observational study of antimicrobial consumption. Global consumption trends were calculated and expressed as DDD/100 bed days and DDD/100 discharges. Trends in antimicrobial consumption were analyzed using a simple linear regression model to determine potential differences in antimicrobial usage throughout the study’s duration. Results: A statistically significant increase in the consumption expressed in DDD/100 discharges was observed in the following groups: carbapenems, 7.6% (trend: 64.68, p < 0.0001), trimethoprim-sulfamethoxazole: 12.6% (trend: 16.45, p < 0.0001), quinolones 9.4% (trend: 36.80, p = 0.02), vancomycin 2.0% (trend: 16.30, p = 0.03), echinocandins: 6.0% (trend: 15.17, p = 0.01) and azole antifungals: 12.10% (trend: 102.05, p < 0.0001). Additionally, a statistically significant increase of 10.30% in the consumption of azole antifungals expressed in DDD/100 bed days was observed (p = 0.0008). In contrast, a statistically significant decrease in consumption, expressed in DDD/100 discharges, was identified for cephalosporins −6.0% (p < 0.0001) and macrolides −16.5% (p < 0.0001). Macrolides also showed a downward trend in consumption, as expressed in DDD/100 bed days (−14.3%, p < 0.0001). According to World Health Organization (WHO) access, watch and reserve (AWaRe) classification trend analysis, only the reserve group showed a statistically significant upward change of 9.2% (p = 0.016). Conclusions: This five-year analysis demonstrated trends over time in overall antimicrobial consumption measured in DDD/100 bed days and DDD/100 discharge rates that correlate. In general, for all antimicrobials, after the implementation of antimicrobial stewardship programs (ASP), a downward trend is reported; in contrast, during the COVID-19 pandemic the AMC shows a general upward trend. The comparison between DDD/100 bed days and DDD/100 discharges allows for complementary comparisons to be made regarding antimicrobial exposure in a clinical setting.

Background: Antimicrobial consumption data in Latin America is scarce and usually spread out within different sources for AMC calculations, making it difficult to both standardize and compare regions through similar time frames. The main objective was to analyze antimicrobial consumption trends in Social Security tertiary care hospitals in Costa Rica in the period spanning January 2017 to December 2021, using both defined daily doses (DDD)/100 bed days and DDD/100 discharges. Methods: Retrospective observational study of antimicrobial consumption. Global consumption trends were calculated and expressed in DDD/100 bed days and DDD/100 discharges. Trends in antimicrobial consumption were analyzed using a simple linear regression model to determine potential differences in antimicrobial usage throughout the study’s duration. Results: A statistically significant increase in the consumption expressed in DDD/100 discharges was observed in the following groups: carbapenems: 35.62% (p<0.0001), trimethoprim-sulfamethoxazole: 62.50% (p<0.0001), echinocandins: 20.73% (p=0.01) and azole antifungals: 61.58% (p<0.0001). Additionally, a statistically significant increase of 40.43% in the consumption of azole antifungals expressed in DDD/100 bed days was observed (p=0.0008). In contrast, a statistically significant decrease in consumption expressed in DDD/100 discharges was identified for cephalosporins -21.97% (p<0.0001) and macrolides -51.67% (p<0.0001). Conclusions: This five-year analysis demonstrated trends over time in overall antimicrobial consumption measured in DDD/100 bed days do not correlate with trends in DDD/100 discharge rates. Continually, the comparison between DDD/100 bed days and DDD/100 discharges allows for complementary comparisons to be made regarding antimicrobial exposure in a clinical setting.

Background: Exposure to antimicrobials and Proton Pump Inhibitors (PPIs) are modifiable risk factors for nosocomial Clostridiodes difficile infection (CDI). We investigated the association between these agents and nosocomial CDI over five years. Methods: Nosocomial CDI from January 2017 to December 2021 were included. Consumption trends were analyzed using a simple linear regression model. A correlation analysis was performed using Spearman’s test in two ways: without a time interval and with 1-month interval matching. An interrupted time-series method to evaluate the impact of three key temporal breakpoints on CDI incidence rate was performed using the Poisson regression model. Results: A downward trend for cephalexin, ceftriaxone, clindamycin, gentamicin, macrolides, metronidazole, and penicillin sodium was identified. In contrast, an upward trend was recognized for amoxicillin, ceftazidime/avibactam, ertapenem, fluconazole, ketoconazole, levofloxacin, and tigecycline. Among the antimicrobials that showed a positive association between consumption and the incidence of CDI are clindamycin and cephalosporins after immediate consumption. Moreover, macrolides and metronidazole presented a positive correlation, in both immediate and delayed consumption. PPIs consumption did not show changes and was not associated with nosocomial CDI incidence. The interrupted time series analysis showed no changes at the breakpoints selected. Conclusions: Consumption of clindamycin, cephalosporins, and macrolides showed positive association with CDI, despite having a downtrend in consumption. Specific events, such as the COVID-19 pandemic and the implementation of ASP, have had no correlation with CDI. Further analysis is required in Latin America to advance our understanding of risk factors associated with CDI.