Review of the Pathophysiologic and Clinical Aspects of Hypokalemia in Children and Young Adults: an Update

Abstract

This article examines the regulatory function of the skeletal muscle, renal, and adrenergic systems in potassium homeostasis. The pathophysiologic bases of hypokalemia, systematic approach for an early diagnosis, and therapeutic strategy to avert life-threatening complications are highlighted. By promoting skeletal muscle uptake, intense physical exercise (post), severe trauma, and several toxins produce profound hypokalemia. Hypovolemia due to renal and extra-renal fluid losses and ineffective circulation activate secondary aldosteronism causing urinary potassium wasting. In addition to hypokalemic alkalosis, primary aldosteronism causes low-renin hypertension. Non-aldosterone mineralocorticoid activation leading to low-renin and low-aldosterone hypertension occurs in Liddle’s syndrome and apparent mineralocorticoid excess. Although there is enzymatic inhibition of cortisol synthesis in congenital adrenal hyperplasia, precursors of aldosterone produce low-renin hypokalemic hypertension. In addition to the glucocorticoid effect, hypercortisolism activates mineralocorticoid receptors in Cushing’s syndrome. Genetic mutations involving furosemide-sensitive Na + -K + -2Cl − co-transporters and thiazide-sensitive Na + -Cl − transporters result in (non-hypertensive) salt-wasting nephropathy. Proximal and distal renal tubular acidosis is associated with hypokalemia. Eating disorders causing hypokalemia include bulimia, laxative abuse, and diuretic misuse. Low urinary potassium (<15 mmol/day) and/or low urinary chloride (<20 mol/L) suggest a gastrointestinal pathology. Co-morbidity of hypokalemia with chronic pulmonary and cardiovascular diseases may increase the fatality rate.

Clinical Overview and Treatment of Hypokalemia in Pediatric Patients: A Narrative Literature Review

“…Diarrhea is a common cause of hypokalemia in children. 1,15 Redistribution of potassium occurs when potassium is shifted from the extracellular fluid to the…”

“…Hypokalemia is a condition characterized by a low level of potassium in the blood (less than 3.5 mmol/L) and is a common electrolyte disorder in pediatric and adult patients. 1 Potassium is an important mineral that helps regulate muscle and nerve function, maintain proper fluid balance in the body, and support normal heart function. 2 In children, hypokalemia can be caused by a variety of factors, such as inadequate potassium intake, excessive loss of potassium through vomiting or diarrhea, certain medications, or underlying medical conditions.…”