Hyperparathyroidism

Hyperparathyroidism is an endocrine disease in which one or more of the four parathyroid glands (located in the neck behind the thyroid gland) produce an excessive amount of parathyroid hormone (PTH).

The main function of PTH is to regulate calcium and phosphorus levels in the blood. Overproduction of PTH leads to extracting too much calcium from the bones and increasing its reabsorption in the kidneys, resulting in high levels of calcium in the blood (hypercalcemia). In most cases (about 85%), the cause is a benign tumor (adenoma) of one of the glands. Less commonly, it may be caused by an enlargement of all four glands or, very rarely, by cancer.

Symptoms

Early hyperparathyroidism often progresses without symptoms and is discovered incidentally during routine blood tests. When symptoms occur, they are usually associated with organ damage caused by high calcium levels and include:

• Bone pain and weakness: Due to loss of calcium from the bones, which can lead to osteoporosis and easy fractures.
• Fatigue and muscle weakness: Chronic fatigue and lethargy.
• Kidney problems: High calcium levels can cause kidney stone formation, leading to pain, nausea, and vomiting.
• Gastrointestinal issues: Constipation, nausea, vomiting, and decreased appetite.
• Mental health issues: Depression, difficulty concentrating, and memory impairment.
• Excessive thirst and frequent urination (polyuria), resulting from the effect of calcium on the kidneys.

Diagnosis

The diagnosis is made through blood tests that show simultaneously elevated calcium levels and elevated or inadequately normal levels of parathyroid hormone (PTH). Vitamin D levels are also measured as its deficiency can affect PTH. After confirming the hormonal and calcium imbalance, imaging studies (such as ultrasound or scintigraphy with Sestamibi) are conducted to locate which parathyroid gland is overactive, as well as tests to assess bone density (osteodensitometry).

Treatment

Treatment depends on the severity of the condition and the presence of symptoms.

Surgical treatment (Parathyroidectomy): This is the only definitive treatment and is highly recommended for all symptomatic patients and those with high calcium levels. During surgery, the overactive gland (usually the adenoma) is removed, which quickly normalizes calcium and PTH levels. The surgery is minimally invasive and usually has a very high success rate.

Observation: In mild cases that are asymptomatic, “active observation” with regular monitoring of calcium levels, bone density, and kidney function may be applied.

Medication treatment: It is mainly used in patients who cannot undergo surgery. Medications like Cinacalcet, which reduce PTH production, and bisphosphonates to protect bones from calcium loss, are administered.

Synonyms: Hyperactivity of the parathyroid glands