Introduction:

Acute kidney injury is a complex, multicausal disorder associated with high mortality and chronic dialysis dependence. The evolution of patients who required renal replacement therapy due to acute kidney injury in Argentina is unknown. Methods: Prospective, observational, longitudinal, multicentric study in individuals over 14 years of age admitted to public hospitals (Province of Santa Fe) with a diagnosis of acute kidney injury and need for renal replacement therapy; study duration: two years (2017 and 2018). Results: Total 255 patients. Frequency 164 ppm/year, 1.85/1000 hospitalizations/year, males 70.98%, age 46.66 years, comorbidities present in 71.37%, hospitalization in critical care 89.02%, extra renal involvement 82.52%. Most frequent causes: arterial hypotension 62.35%, infections 52.73%, nephrotoxic 17.65%. Renal replacement therapy: intermittent hemodialysis 74.51%, sustained low-efficiency dialysis 11.76%, continuous: 13.73%. Evolution: alive at 30 days 116 (45.49%), chronic dialysis dependence 12 (10.34%). Mortality: at 30 days 54.51%, progressing to 65.88% at 420 days. No significant difference in mortality at 30 days according to age, sex, renal replacement therapy, comorbidities or creatinine in first dialysis. There was a significant difference (p <0.05) in mortality in isolated acute renal injury extra renal involvement (RR: 1.55), Critical Care Unit vs Ward (RR: 3.31) and arterial hypotension as cause (RR: 1.79). Patients with chronic dialysis dependence presented higher mortality than those who recovered renal function (50% vs 22%, RR: 2.26). Conclusions: This is the first epidemiological study with follow-up of the population that required renal replacement therapy in Argentina. It is composed of young, severe patients with a high proportion of extra renal organ involvement. Mortality is high and continues beyond the onset of renal replacement therapy, chronic dialysis dependence leads to a worse vital prognosis.