Hypokalemia in Children

Definition and Etiology
Hypokalemia is defined as a serum potassium <3.5 mEq/L.

It is a result of potassium losses in excess of replacement. Potassium can be lost through the GI tract as well as the kidneys.

Clinical Presentation and Physical Examination
Symptoms: constipation, fatigue, muscle weakness, and paralysis

Physical examination

• Check for possible irregular heartbeat.
• Evaluate for signs of muscle weakness/paralysis.

Differential Diagnosis

• Decreased intake as a result of low dietary intake or IV fluids without potassium
• Increased GI losses from vomiting, nasogastric suction, or diarrhea
• Increased urinary losses because of loop and thiazide diuretics
• Mineralocorticoid excess
• Liddle syndrome (autosomal dominant with increased sodium resorption)
• Bartter or Gitelman syndromes
• Amphotericin
• Hypomagnesemia

Treatment

• Administer oral or IV potassium supplements.
• Correct hypomagnesemia.
• Stop diuretics and amphotericin if possible.