Sodium and potassium are important electrolytes involved in many of the body's functions. Sodium is important for fluid balance, while potassium is important for muscle contraction and the heart's rhythm. Several conditions can cause both high sodium and low potassium. The main cause of this electrolyte disturbance is conditions that affect the level of the hormone aldosterone.
Facts about Aldosterone
Aldosterone is a hormone secreted by the adrenals, a pair of triangular shaped glands that sit on top of the kidneys. According to Lab Tests Online, aldosterone stimulates the kidneys to retain sodium and excrete potassium from the urine. Overproduction of aldosterone results in a condition called hyperaldosteronism. According to the National Library of Medicine, primary hyperaldosteronism results from a problem within the adrenal gland that makes it secrete excess aldosterone. Secondary hyperaldosteronism results from excess aldosterone produced somewhere else in the body.
Primary hyperaldosteronism, which is a rare condition, is usually caused by the presence of a benign tumor within the adrenal gland that stimulates the secretion of aldosterone. This usually occurs in people between the ages of thirty and fifty years old. Secondary hyperaldosteronism is related to certain chronic conditions, for example, liver cirrhosis, which is the shrinking and scarring of the liver resulting from chronic alcoholism; heart failure; and nephrotic syndrome, a condition in which the kidneys are damaged and allow proteins to leak out into the urine.
The symptoms of hyperaldosteronism include high blood pressure, fatigue, weakness, headache, and blurry vision. The high sodium content causes increased thirst. Hypernatremia, or high sodium, can cause brain shrinkage, which can result in confusion, seizures and coma. Low potassium, or hypokalemia, causes muscle spasms and cramps, weakness, constipation, and cardiac arrhythmias, or dangerous abnormal heart rhythms.
The treatment of primary hyperaldosteronism depends on its cause. If a tumor is present in the adrenal gland, surgical removal will cause the aldosterone level to normalize. Conditions that cause secondary hyperaldosteronism can be difficult to diagnose and treat, but if controlled, can lead to improvement of the symptoms. High sodium levels need to be corrected slowly, to prevent brain swelling, or edema. Likewise, normalization of severely low potassium levels needs to happen in a closely monitored hospital environment, where slow intravenous infusions of potassium can be administered without the risk of causing cardiac arrhythmias.