Acute kidney injury in kids: When do they need dialysis?

Kidneys helps to make sure that our bodies are healthy when they remove waste from the body, balancing fluids and salts, and regulating blood pressure. Sudden failure of the kidneys to operate normally is called Acute Kidney Injury (AKI). In children, AKI may arise over hours or days and be life, threatening if untreated.

Causes AKI in Children:

• Dehydration that is due to severe vomiting and diarrhoea or insufficient fluid intake
• Severe infections or sepsis
• Immunologic injury, like glomerulonephritis or haemolytic uremic syndrome (HUS)
• Certain medications that harm the kidneys
• Obstruction of the urine (for example, by a stone, abnormal structure, or congenital problem)

Symptoms to Watch For:

• Reduced or no urine output
• Facial, feet, or leg swelling
• High blood pressure
• Fatigue, irritability, or poor appetite
• With severe dehydration, a person may experience nausea, vomiting, or confusion

AKI is diagnosed by:

• Blood tests to screen for waste products like creatinine and urea
• Urine tests for protein, blood, or signs of kidney dysfunction
• Ultrasound scans to detect blockages or structural issues

How Is AKI Treated?

Treatment is contingent upon the cause and severity of injury. The aim is to treat the underlying cause and prevent additional kidney injury.

Supportive care includes:

• Medications: These could be used to treat infection, blood pressure issues, or electrolyte imbalance
• Fluid management: giving fluids to dehydrated patients or restricting fluid intake when patient has fluid overload
• Avoiding nephrotoxicity: Some antibiotics or analgesics may contribute to kidney damage and should be avoided

When is dialysis necessary?

Dialysis is necessary when the kidneys can no longer maintain homeostasis, despite medical management. The term "AEIOU" is a terrific way to remember the primary indications for dialysis:
• A - Acidosis: Severely acidic blood that has not improved with medications
• E - Electrolyte Imbalance: Hyperkalemia or elevated potassium
• I - Intoxication: Poisonings that can be removed by dialysis
• O - Overload: Too much fluid with resulting edema, high BP, or difficulty breathing
• U - Uremia: Waste products that have retained and resulted in confusion, vomiting, seizures, or inflammation of the heart.

Dialysis Methods in Children:

1. Peritoneal Dialysis (PD): More conservative approach, fluid is infused into the abdominal cavity so the waste can be absorbed. Best method for an infant and small child.
2. Hemodialysis (HD): Blood pulled through a machine. Quick and effective, but requires more intervention and is reserved for urgent situations.
3. Continuous Renal Replacement Therapy (CRRT): CRRT is performed in the ICU for critically ill children, and is done slowly over 24 hours.
4. Sustained Low-Efficiency Dialysis (SLED): A middle-ground approach when CRRT is unavailable.

Can Children Recover?

Yes, if treated quickly, almost all children can fully recover. Some children may develop chronic kidney problems and require retesting and management for the rest of their lives.

What can Parents do?

• Ensure your child is drinking enough, especially when sick or it is hot
• Make sure you seek medical help fast if your child has vomiting, diarrhoea or few hours (24 hours or more) of decreased urine output
• Do not give over-the-counter medications without checking with your doctor
• Don’t forget to follow up if your child has kidney issues or if he/she was in the ICU

(Dr. Swathi Rao, Consultant - Pediatric Intensivist, KMC Hospital, Mangalore)