1- do ABG electrolytes for monitoring the condition
2- correct hyper natremia gradually with special fluid therapy
3- if K is 3.5 to 2.5 correct by oral syrup: 1mg/ kg/ day and follow up the labs
4- do anion gap if any metabolic acidosis if normal: RTA- GE, if high : cosider inborn errors of metabolism
5- do abd Us if any renal nephropathy or organomegaly