What are the symptoms of Conn's syndrome (primary hyperaldosteronism)?Symptoms of Conn's syndrome include high blood pressure, headache, tiredness, and excessive urination (often during the night). Also, the level of potassium in the blood may be decreased. Other symptoms may occur because high aldosterone levels in the blood act on the kidney to increase the loss of the mineral potassium in the urine. This in turn may lead to a fall
in blood potassium, resulting in tiredness, muscle weakness and passing of large volumes of urine (polyuria), especially at night (nocturia). However, these symptoms are also found in many other conditions (for example, diabetes mellitus or hypercalcaemia) and do not, by themselves, establish a diagnosis of Conn's syndrome. Also, many patients with proven Conn's syndrome do not have a low blood potassium level.
In hyperaldosteronism, excess aldosterone leads to an inappropriate salt reabsorption, which increases the extracellular fluid volume until the kidneys can respond appropriately. Patients typically have mild to moderate hypertension. Primary hyperaldosteronism can be distinguished from basic hypertension through blood tests. In general, hyperaldosteronism is unresponsive to standard medical therapy used to prevent or reduce high blood pressure.
Mild hypernatremia (high blood sodium), hypokalemia (low blood potassium), hyperkaluria (high urine potassium) and high levels of alkalinity are the electrolyte abnormalities commonly seen with excess aldosterone. These contribute the following symptoms: muscle weakness, frequent urination, nighttime urination, headache, excessive thirst, pins and needles sensation, visual disturbances, temporary paralysis, muscle twitching and cramps. The severity of these symptoms may be highly variable depending on the degree of electrolyte abnormality.