This clinical trial will evaluate Renastart formula effectiveness in children with acute kidney injury (AKI) and acute on top of chronic kidney disease (CKD), in maintaining normal serum electrolytes levels without using electrolyte binders,24 patients will be recruited from Pediatric Nephrology Unit (PNU), Children's Hospital, Ain Shams University, they will be assigned randomly in to two arms, arm 1 including patients who will be treated by electrolytes binders, arm 2 including patients who will be treated by Renastart formula, after initial assessment serum electrolyte evaluation will be followed up monthly for 3 months.

Inclusion Criteria:

•Infants and Children with AKI and acute on top of CKD Suffering from hyperkalemia and/or hyperphosphatemia at Pediatric Nephrology Unit (PNU), Children's Hospital, Ain Shams University Hospitals.

Exclusion Criteria:

• Patients are on dialysis.
• Pediatric patients with coexisting another medical problems and different risk factors which can affect serum electrolytes such as: Constipation, high volume blood transfusion and Diabetes medications disrupt potassium balance e.g., ACEI, ARBS and Diuretics.