Recurrent Hypokalemia in A Child

Severe hypokalemia is a medical emergency that could lead to cardiac arrest if untimely recognized.1 Here, we present a practical approach to hypokalemia. A 1-year-6-month-old girl with proper growth and development had recurrent vomiting and hypokalemia in the past 2 months. Laboratory studies demonstrated serum Na+ of 132 mmol/L, K+ of 1.9 mmol/L, Cl− of <80 mmol/L, HCO3− of 42.9 mmol/L, blood urea nitrogen of 22.3 mg/dL, creatinine of 0.33 mg/dL, and osmolality of 271 mOsm/KgH2O. Urine analysis showed K+ of 122.5 mmol/L, creatinine of 61 mg/dL, osmolality of 809 mOsm/KgH2O, and trans-tubular potassium gradient (TTKG) of 22 on admission and Na+ of 64, K+ of 19.6, and Cl− of <15 mmol/L on the second hospital day.