Acute kidney injury (AKI) has been traditionally defined as an abrupt loss of kidney function leading to a rapid decline in the glomerular filtration rate (GFR), accumulation of waste products such as blood urea nitrogen (BUN) and creatinine, and dysregulation of extracellular volume and electrolyte homeostasis . Acute kidney injury (AKI) is a very common condition, especially among hospitalized patients.

this work aims to study the demographics, etiology, clinical characteristics, and outcome of acute kidney injury in children in Sohag University Hospital - Pediatrics Department.

Inclusion Criteria:

• All children with acute kidney injury with an age range from 1 month to 16 years old

Exclusion Criteria:

1. patients with chronic kidney disease (CKD)
2. Patients with irregular follow up
3. Patients with incomplete data
4. Patients whose medical guardians refuse participation in the study

Acute kidney injury (AKI) will be defined by the presence of an Increase in serum creatinine by 0.3 mg/dL or more within 48 hours, or increase in serum creatinine to 1.5 times or more baseline within the prior seven days, or urine output less than 0.5 mL/kg/h for at least 6 hours . AKI will be classified according to serum creatinine level (SCr) and urine output as in table .