Acute kidney injury (AKI) is a common clinical syndrome, especially in the hospital patients. AKI is recognized as an important risk factor for incident chronic kidney disease, accelerated progression to end-stage renal disease,and increased risk of short-term and long-term mortality.This study is to observe the prognosis of hospitalized patients with AKI in China.

Inclusion Criteria:

• clinically diagnosed with acute kidney injury, according to KDIGO criteria

Exclusion Criteria:

• Nephrectomy
• Kidney transplantation
• Peak serum creatinine of less than 53µ mol/L
• Serum creatinine decrease after amputation
• Patients died during hospitalization
• End-stage kidney disease(chronic kidney disease stage 5)
• malnutrition

Hospitalized patients