The adrenal glands, small, triangular-shaped organs, sit atop each kidney. These glands are a crucial part of the endocrine system, producing various hormones essential for regulating metabolism, blood pressure, and the body’s stress response. Sometimes, an adrenal nodule can develop on these glands. Adrenal nodules are relatively common, with up to 7% of people having one by age 70.
Understanding Adrenal Nodules
Adrenal nodules are categorized primarily by their hormonal activity. Functional nodules produce excess hormones, while non-functional nodules do not. The majority are non-functional. These growths often emerge due to age-related changes, though their exact causes are frequently unclear.
While most adrenal nodules are benign, a small percentage can be malignant. Benign adrenal adenomas are the most common type of adrenal gland tumor, originating from the outer part of the gland, the adrenal cortex. Certain inherited disorders can increase an individual’s risk.
Symptoms of Hormone Overproduction
When adrenal nodules become functional, they produce an excessive amount of specific hormones, leading to a variety of symptoms. These symptoms depend on which hormone is being overproduced, and they can significantly affect a person’s health. Recognizing these specific signs is important for a timely evaluation.
Cortisol
Excessive production of cortisol, a hormone that helps regulate metabolism and the body’s response to stress, leads to a condition known as Cushing’s Syndrome. Symptoms often include significant weight gain, particularly around the face, neck, and trunk, sometimes described as a “moon face” or a “buffalo hump” between the shoulders. The skin may become thin and bruise easily, with characteristic pink or purple stretch marks appearing on the abdomen, hips, and breasts. Individuals might also experience high blood pressure, elevated blood sugar levels, muscle weakness, and changes in mood such as anxiety or depression. In women, increased facial hair growth and irregular menstrual periods can also occur.
Aldosterone
Aldosterone plays a role in regulating blood pressure by managing sodium and potassium levels. Overproduction of aldosterone, a condition called Conn’s Syndrome or primary aldosteronism, causes high blood pressure. This hypertension is often resistant to conventional medication, requiring multiple drugs for control. Low potassium levels are also common, leading to muscle weakness, fatigue, cramping, and increased urination. Headaches are also frequent.
Catecholamines
The adrenal glands also produce catecholamines, such as adrenaline and noradrenaline, involved in the body’s “fight or flight” response. A nodule that produces too many of these hormones is called a pheochromocytoma. Symptoms often appear as sudden, episodic attacks, including dramatically high blood pressure, rapid heart rate, and palpitations. Profuse sweating, severe headaches, tremors, and feelings of anxiety or panic are also common during these episodes. Though typically benign, pheochromocytomas can cause serious health problems if untreated.
Androgens and Estrogens
In rare instances, adrenal nodules may produce an excess of androgens. In women, this can lead to symptoms such as increased facial and body hair growth, acne, and changes in voice or menstrual cycles. Conversely, excess estrogen production in men might cause breast enlargement or decreased sex drive.
When Nodules Cause No Symptoms
Many adrenal nodules do not produce hormones and cause no noticeable symptoms. These asymptomatic growths are often discovered incidentally during imaging scans, such as CT or MRI, performed for unrelated medical conditions. They are referred to as “adrenal incidentalomas.”
The increased use of advanced imaging technologies has made the incidental discovery of these nodules more common. For instance, a scan for abdominal pain or kidney stones might inadvertently reveal an adrenal nodule. While most incidentalomas are benign, they still warrant careful evaluation to rule out the possibility of malignancy or subtle hormone overproduction.
When to Talk to a Doctor
If you experience any unexplained or concerning symptoms that could be related to hormone imbalances, consult a doctor. This includes persistent or unexplained high blood pressure, particularly if difficult to control. Sudden weight changes, new diabetes, or episodes of rapid heart rate with sweating and headaches also warrant discussion. A medical evaluation is important for diagnosis and management.