Liddle syndrome is a rare hereditary disorder in which the kidneys excrete potassium but retain too much sodium and water, leading to high blood pressure.
The gene that causes Liddle syndrome is dominant, meaning that children of a person with the disorder have a 50% chance of inheriting the defective gene. The disorder does not always cause symptoms. When it does, symptoms such as high blood pressure often begin during childhood or young adulthood. Some people have low levels of potassium in the blood.
In addition to measuring blood pressure, doctors measure the amount of sodium in the urine. They may also do blood tests to detect levels of hormones that help regulate sodium levels in the blood and thus blood pressure (renin and aldosterone). Genetic testing may also be done.
The condition is effectively treated by drugs that increase sodium excretion and lessen potassium excretion, such as triamterene or amiloride. These drugs effectively lower the blood pressure. The prognosis is very good.
Last full review/revision July 2013 by James I. McMillan, MD