Survival and renal recovery after acute kidney injury requiring dialysis outside of intensive care units.

BACKGROUND: The incidence of acute kidney injury requiring dialysis (AKI-D) is increasing globally and it is usually associated to chronic kidney disease (CKD) and high mortality. Literature is lacking in short- and intermediate-term data on recovery of renal function after acute kidney injury (AKI). OBJECTIVES: The objective was to evaluate the overall survival and renal recovery after an episode of AKI requiring dialysis out of intensive care units (ICUs). MATERIALS AND METHODS: Retrospective study including patients admitted in two nephrology units along a period of 2 years. Patients admitted to ICUs and renal transplant patients were excluded. Baseline renal function, mortality and glomerular filtration rate (GFR) improvement were evaluated. RESULTS: 151 consecutive adult patients with AKI requiring renal replacement therapy (RRT) were included. Mean age was 70.5 ± 15.2 years, 60.3% were males. Median baseline creatinine (bCr) and baseline GFR (bGFR) were 1.4 mg/dL and 46 mL/min/1.73 m2, respectively. After 1 year of follow-up, we completed the monitoring of 94 patients: 64.9% had died, 10.6% were alive on dialysis and 24.5% were alive without need for RRT. Patients with bGFR > 60 mL/min/1.73 m2 prior to AKI episode had a slower but sustained GFR improvement through the follow-up in comparison with patients with bGFR < 60 mL/min/1.73 m2 whose recovery was incomplete. CONCLUSIONS: Patients with AKI requiring RRT have high short- and intermediate-term mortality and some require maintenance dialysis. Patients with GFR > 60 mL/min/1.73 m2 prior to AKI had a renal recovery closer to the basal renal function than in patients with a previously diminished GFR.