Implementation and impact of an antibiotic control program and multidrug-resistant bacterial colonization in a liver transplant unit.

INTRODUCTION: infections by multidrug-resistant bacteria are a major cause of morbidity and mortality in transplant patients. OBJECTIVE: a retrospective single-center study was performed to evaluate the implementation of an Antimicrobial Treatment Optimization Program (PROA) on multidrug-resistant bacteria colonization and infection after liver transplant (LT). METHODS: colonization by multidrug-resistant bacteria and infections during the first year after a liver transplant were analyzed in a group of 76 transplanted patients in two stages, before and after PROA (2016-2019). Clinical variables related to infection, readmissions and survival one year after the liver transplant were analyzed. RESULTS: there was good adherence to the PROA. Infection was the most frequent cause for readmission during the first year after the liver transplant. Incidence of infections was similar during both periods (mean of 1.25 and 1.5 episodes of bacterial infection per patient/year, respectively) with 19 bacterial infectious episodes, six by hospital-acquired multidrug-resistant and extensively drug-resistant (MDR-XDR) bacteria in the pre-PROA stage, and 18 bacterial infectious episodes, five by MDR-XDR in the post-PROA stage. A 37 % decrease of post-TH of rectal colonization by MDR-XDR after liver transplant was observed during 2019. CONCLUSIONS: epidemiological surveillance policies and antibiotic optimization are key to control the increase of colonization and infection by multidrug-resistant bacteria in liver transplant units. Long-term studies are needed to better evaluate the impact of these programs.

Implantación e impacto de un programa de control antibiótico y colonización por bacterias multirresistentes en una unidad de trasplante hepático / Implementation and impact of an antibiotic control program and multidrug-resistant bacterial colonization in a liver transplant unit

Introducción: las infecciones por bacterias multirresistentes constituyen una importante causa de morbimortalidad pre coz en los pacientes trasplantados.Propósito: se presenta un estudio unicéntrico, retrospectivo, con objetivo de evaluar la implantación de un programa de optimización del uso de antibióticos y de control epidemio lógico (PROA) en la colonización e infección por bacterias multirresistentes tras el trasplante hepático (TH).Métodos: se analizaron la colonización por bacterias multi rresistentes y las infecciones en el primer año postrasplante hepático (post-TH) en un grupo de 76 pacientes trasplanta dos en dos etapas, anterior y posterior al PROA, entre los años 2016 y 2019. Se analizaron variables clínicas relacio nadas con infección, reingresos y supervivencia a un año.Resultados: se produjo una buena adherencia al PROA. Las infecciones en el primer año post-TH fueron la causa más fre cuente de reingreso. La incidencia de infecciones fue similar en ambos periodos, con una media de 1,25 y 1,5 episodios de infección bacteriana por paciente/año con 19 episodios infecciosos bacterianos, seis por bacterias multirresistentes y de resistencia extendida (MDR-XDR) en la etapa pre-PROA y 18 episodios infecciosos bacterianos, cinco por MDR-XDR. en la etapa posterior. Se objetivó un descenso del 37 % post TH de colonización rectal por MDR-XDR durante el año 2019.Conclusión: las políticas de vigilancia epidemiológica y optimización de antibióticos son necesarias como estrategia de control del incremento de colonización e infección por bac terias multirresistentes en unidades de trasplante hepático. Son necesarios estudios a largo plazo para evaluar mejor el impacto de estos programas (AU)

Molecular characterization of multidrug resistant Enterobacterales strains isolated from liver and kidney transplant recipients in Spain.

The objective of this study was to analyse the mechanisms of resistance to carbapenems and other extended-spectrum-ß-lactams and to determine the genetic relatedness of multidrug-resistant Enterobacterales (MDR-E) causing colonization or infection in solid-organ transplantation (SOT) recipients. Prospective cohort study in kidney (n = 142), liver (n = 98) or kidney/pancreas (n = 7) transplant recipients between 2014 and 2018 in seven Spanish hospitals. We included 531 MDR-E isolates from rectal swabs obtained before transplantation and weekly for 4-6 weeks after the procedure and 10 MDR-E from clinical samples related to an infection. Overall, 46.2% Escherichia coli, 35.3% Klebsiella pneumoniae, 6.5% Enterobacter cloacae, 6.3% Citrobacter freundii and 5.7% other species were isolated. The number of patients with MDR-E colonization post-transplantation (176; 71.3%) was 2.5-fold the number of patients colonized pre-transplantation (71; 28.7%). Extended-spectrum ß-lactamases (ESBLs) and carbapenemases were detected in 78.0% and 21.1% of MDR-E isolates respectively. In nine of the 247 (3.6%) transplant patients, the microorganism causing an infection was the same strain previously cultured from surveillance rectal swabs. In our study we have observed a low rate of MDR-E infection in colonized patients 4-6 weeks post-transplantation. E. coli producing blaCTX-M-G1 and K. pneumoniae harbouring blaOXA-48 alone or with blaCTX-M-G1 were the most prevalent MDR-E colonization strains in SOT recipients.