Acute kidney injury (AKI) is a sudden decrease in kidney function, which can occur within hours or days. This condition can lead to the accumulation of waste products in the blood and disrupt the balance of fluids and electrolytes. Common causes of AKI include dehydration, certain medications, and severe infections. Symptoms of AKI may include decreased urine output, swelling in the legs or ankles, and fatigue. Diagnosis typically involves blood tests to measure creatinine levels and urine tests to assess kidney function. Early detection and treatment are crucial to prevent long-term damage to the kidneys.