PA Differential Diagnoses
Other endocrine and genetic conditions can cause symptoms similar to those associated with primary aldosteronism. When the results of diagnostic testing are inconclusive, it is important to consider these conditions as a possible cause of difficult to control hypertension.
With this condition, the pituitary gland produces too much growth hormone during adulthood, typically around middle age. As a result, the bones in the feet, hands, and face gradually increase in size, making the condition difficult to recognize at first. Hypertension, cardiovascular disease, and diabetes are some of the more common complications.
Apparent Mineralocorticoid Excess (AME)
In this rare autosomal recessive disorder, patients have hypertension, hypokalemia, low renin, and hypoaldosteronism (low plasma aldosterone).
This endocrine disease occurs when the body is exposed to too much cortisol. The most common cause is a small tumor on the pituitary gland. In some instances, the disease may be caused by an adrenal adenoma and coexist with primary aldosteronism which is then called “Connshing Syndrome.” Although the exact prevalence is unknown, some 20 to 30% of adrenal tumors may secrete excess levels of both cortisol and aldosterone.
Patients with Cushing’s often experience unexplained weight gain, high blood pressure, diabetes, muscle weakness, osteoporosis, easy bruising, purple stretch marks, and brain fog. Like primary aldosteronism, since many of these symptoms are found in other conditions, it is common for Cushing’s to go undiagnosed for many years. Saliva, blood, and urine tests are used to assess cortisol levels.
Excessive Licorice Consumption
Although this is not a medical condition, it is important to note that licorice — a popular sweetener used in various foods, sodas, snacks, and herbal medicines — can be toxic when ingested in high quantities. Glycyrrhetic acid, the active ingredient of licorice, causes sodium reabsorption and potassium excretion, and eventually results in hypertension and hypokalemia.
Also called pseudohypoaldosteronism type 2, this rare genetic condition is characterized by low plasma aldosterone and hyperkalemia.
The parathyroid regulates the amount of calcium and phosphorous in the blood. When parathyroid levels are too high, blood levels of calcium rise and this causes hypertension. Patients with primary aldosteronism are prone to secondary hyperparathyroidism. When primary aldosteronism causes too much calcium to be excreted in the urine, parathyroid levels rise in an effort to maintain adequate calcium levels in the blood. This process is usually associated with osteoporosis as calcium is drawn out of the bones.
This genetic disorder causes a defect in the sodium channel leading the kidneys to retain sodium and excrete potassium. Patients usually experience severe hypertension and hypokalemia, but unlike patients with primary aldosteronism, their plasma aldosterone is very low. Severe hypertension typically begins early in life, but some patients may not show symptoms and only be diagnosed in adulthood.
Instead of excess aldosterone, a pheochromocytoma produces excess epinephrine and norepinephrine, two hormones that control heart rate, metabolism, and blood pressure. Like some forms of primary aldosteronism, the disease is caused by a usually benign tumor of the adrenal gland. Patients with a pheochromocytoma may experience periodic and sudden spikes in their blood pressure, tachycardia, heavy sweating, anxiety, headaches, and shortness of breath. Initial tests for the condition include a blood test and a 24-hour urine collection to measure fractionated metanephrines (the chemical byproducts of epinephrine and adrenaline).
While it can have multiple causes, secondary hyperaldosteronism is often due to a restriction of blood flow to the kidneys (i.e., renal arterial stenosis). In this instance, the kidney interprets the lack of blood flow as low blood pressure and raises both renin and aldosterone in an effort to compensate. Ultrasound imaging of the renal arteries usually makes it possible to confirm this condition.
Either too much thyroid hormone (hyperthyroidism) or too little thyroid hormone (hypothyroidism) can lead to hypertension. A simple blood test can determine whether thyroid levels are within range.
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