A rise in cystatin C ≥ by 0.3 mg / L within 48 h after hospitalization (AKIcys) occurred in 35% of patients and resulted in 2 days (p = 0.05) longer hospital stay and was associated with significantly higher in-hospital mortality, odds ratio 9.1 [95% confidence intervals (CI) 3.05 - 32.35, p < 0.001].