RÉSUMÉ
Background: The rise of infections caused by multidrug-resistant Gram negative bacilli (MDR-GNB), added to paucity of newer therapy, have led to increase polymyxin B use, despite adverse renal toxicity profile. Aim: To determine the incidence and risk factors associated to acute kidney injury (AKI) and polymyxin B use, in patients with infections caused by MDR-GNB. Methods: A retrospective cohort, with a nested case-control study of adults who received polymyxin B for more than 48 hours at a tertiary university hospital in Colombia (2011-2015) was performed. AKI was defined by AKIN criteria. Results: Of 139 patients included in our study, 102 were male with median age of 49 years (IQR:28-64). Sixty-one patients (44%) developed AKI. Independent risk factors for development of AKI included: total polymyxin B daily dose (OR = 2.19, 95% CI, 1.04-4.64); length of stay at ICU (OR = 1.03, 95% CI, 1.00-1.06); nosocomial infection (OR = 6.43, 95% CI, 2.12, -19.47); and vasopressor use (OR = 5.38, 95% CI, 2.40-12.07). Mortality was higher among AKI-patients (58.6%) compared with non-AKI patients (25.6%) (p = 0.001). Conclusion: In this study, the rate of AKI associated to polymyxin B use was greater than reported in studies from last decade, and associated with increased mortality. AKI associated to polymyxin B use is likely multifactorial and aggravated by the critically ill state of patients suffering nosocomial infections caused by mdr-gnb.
Introducción: El surgimiento de infecciones graves causadas por bacilos gramnegativos multi-resistentes (BGN-MR), sumado a la carencia de nuevas opciones terapéuticas efectivas, ha llevado a retomar el uso de polimixina B, a pesar de su perfil de nefrotoxicidad. Objetivo: Determinar la incidencia y factores relacionados con el desarrollo de nefrotoxicidad asociada al uso de polimixina B, en pacientes adultos con infecciones causadas por BGN-MR. Materiales y Métodos: Estudio observacional, analítico, tipo cohorte histórica, con un análisis de casos y controles anidado, realizado en un hospital universitario de tercer nivel de Colombia entre 2011 y 2015, en pacientes que recibieron polimixina B intravenosa por más de 48 h. Resultados: De 139 pacientes incluidos en el estudio, 61 (44%) desarrollaron falla renal aguda por criterios AKIN. Los factores de riesgo independientes para nefrotoxicidad fueron: dosis diaria de polimixina B (OR 2,19; IC 95% 1,04-4,64), días de estancia en UCI (OR 1,03; IC 95% 1,00-1,06), presencia de infección nosocomial (OR 6,43; IC 95% 2,12-19,47) y requerimiento de fármacos vasopresores (OR 5,38; IC 95%: 2,40-12,07). Conclusión: La tasa de nefrotoxicidad observada en pacientes que recibieron polimixina B es considerable; su origen probablemente multifactorial y agravada por estado crítico de pacientes con infecciones nosocomiales por BGN-MR.