Liddle syndrome is a rare hereditary disorder involving increased activity of the epithelial sodium channel (ENaC), which causes the kidneys to excrete potassium but retain too much sodium and water, leading to hypertension. Symptoms are of hypertension, fluid retention, and metabolic alkalosis. Diagnosis is through measurement of urinary electrolytes. Potassium-sparing diuretics provide the best treatment.
Liddle syndrome is a rare autosomal dominant disorder of renal epithelial transport that clinically resembles primary aldosteronism, with hypertension and hypokalemic metabolic alkalosis and with low plasma renin and aldosterone levels. The syndrome results from an inherently increased activity of the epithelial sodium channels (ENaC), located on the luminal membrane in the collecting tubule, which accelerates sodium resorption and potassium secretion (underactivity of ENaC causes sodium excretion and potassium retention—see Pseudohypoaldosteronism Type I).
Patients with Liddle syndrome present at age < 35 years. Hypertension and symptoms and signs of hypokalemia and metabolic alkalosis occur.
Diagnosis of Liddle Syndrome
Urine sodium level
Plasma renin and aldosterone levels
Diagnosis is suggested by the presence of hypertension in a young patient, particularly one with a positive family history. Low urine sodium (< 20 mEq, or 20 mmol/L), low plasma renin and aldosterone levels, and response to empiric treatment usually are considered sufficient to confirm the diagnosis. Definitive diagnosis can be achieved through genetic testing (see Gene Tests for more information).
Treatment of Liddle Syndrome
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
GTR: Genetic Testing Registry: This central location for genetic test data includes information on the purpose, validity, and usefulness of those tests, which are grouped by helpful search categories (eg, human tests, microbe tests, conditions/phenotypes).
