Understanding Primary Hyperparathyroidism: Diagnosis and Treatment

Overview

Primary hyperparathyroidism, often abbreviated as hyperparathyroidism, is a condition characterized by excessive secretion of parathyroid hormone (PTH), primarily due to abnormalities within the parathyroid glands themselves. This article provides a comprehensive overview of the diagnosis and treatment of primary hyperparathyroidism, emphasizing its clinical manifestations, diagnostic criteria, and therapeutic approaches.

Diagnosis

Clinical Presentation

Primary hyperparathyroidism typically presents gradually with a wide range of symptoms. Key manifestations include:

• Memory loss, mood instability, apathy, and personality changes.
• Fatigue, weakness, muscle atrophy, hallucinations, and mania, which may progress to coma.
• Reduced appetite, bloating, indigestion, constipation, nausea, and vomiting, which can lead to chronic ulcers, pancreatitis, and joint pain.
• Bone pain, especially in the lumbar, hip, ribs, and limbs, with local tenderness.
• Long-term hypercalcemia may affect renal tubular function, leading to polyuria, nocturia, thirst, kidney stones, and renal failure.
• In severe cases, significant hypercalcemia can occur with marked dehydration.

Laboratory and Imaging Tests

To diagnose primary hyperparathyroidism, healthcare providers look for:

• Serum calcium levels consistently above 2.75 mmol/L.
• Serum phosphorus levels generally low.
• Elevated serum alkaline phosphatase levels.
• Increased blood vitamin D levels and serum albumin levels.
• Increased urine calcium and phosphorus levels, as well as increased urinary hydroxyproline levels, indicating significant bone involvement.
• Increased urinary cAMP levels.
• Serum PTH levels above 10 picomoles/L.
• Radiographic studies, including bone density tests and bone ultrasound velocity assessments, showing bone loss and reduced bone density.
• Diagnostic tests to rule out other conditions such as malignancies, vitamin D intoxication, chronic kidney disease, and osteoporosis.

Treatment

Surgical Intervention

Surgical removal of the affected parathyroid gland(s) is the gold standard treatment for primary hyperparathyroidism. This involves:

• Removal of the adenoma (tumor) in cases of a single adenoma.
• Removal of three glands and partial resection of the fourth in cases of hyperplasia.
• Monitoring and management of postoperative hypocalcemia, which may require dietary adjustments, calcium supplements, or intravenous calcium gluconate.

Medications

• Cimetidine may be used in patients with contraindications to surgery or as part of preoperative preparation and for acute primary hyperparathyroidism crisis.
• Calcium and magnesium supplements may be necessary to manage hypocalcemia.

High Calcium Crisis

In cases of hypercalcemia with serum calcium levels above 3.75 mmol/L, known as a high calcium crisis, immediate medical intervention is necessary. This may include:

• Intravenous fluids to restore hydration.
• Parathyroid hormone (PTH) receptor antagonists.
• Calcimimetics to inhibit PTH secretion.
• Diuretics to promote calcium excretion.
• Calcitonin to lower blood calcium levels.
• Hormonal therapy, such as corticosteroids.
• Hemodialysis or peritoneal dialysis in severe cases.

Conclusion

Primary hyperparathyroidism is a complex condition that requires early diagnosis and appropriate management. Understanding the diagnostic criteria and treatment options can significantly improve outcomes for patients. It is crucial for healthcare providers to be aware of the signs and symptoms of this condition and to implement timely and effective treatment strategies.