What is the management approach for a patient with bilaterally enlarged parathyroid (Parathyroid Hormone) glands on neck ultrasound, normal serum calcium, and normal Parathyroid Hormone (PTH) levels?

From the Guidelines

For a patient with bilaterally enlarged parathyroid glands on neck ultrasound but normal serum calcium and normal PTH levels, the recommended approach is watchful waiting with periodic monitoring rather than immediate intervention. This approach is based on the most recent and highest quality study available, which emphasizes the importance of biochemical abnormalities in determining the need for intervention 1. The patient should undergo follow-up laboratory testing every 6-12 months, including:

• Serum calcium
• PTH
• Vitamin D levels
• Renal function tests Repeat neck ultrasound is typically recommended annually to monitor for changes in gland size or characteristics. This conservative management is appropriate because enlarged parathyroid glands without biochemical abnormalities represent an incidental finding rather than primary hyperparathyroidism or other pathology requiring treatment. The patient should be educated about symptoms of hypercalcemia to report, such as:
• Fatigue
• Bone pain
• Kidney stones
• Cognitive changes Adequate vitamin D intake (800-1000 IU daily) and calcium intake (1000-1200 mg daily from diet and supplements combined) should be maintained. The rationale for this approach is that parathyroid gland enlargement can occur without functional abnormalities, and unnecessary surgery carries risks including hypoparathyroidism, recurrent laryngeal nerve damage, and bleeding. Surgical intervention would only be indicated if the patient develops biochemical evidence of hyperparathyroidism or if imaging suggests malignancy, as supported by the guidelines for parathyroidectomy in patients with chronic kidney disease 1. It is also important to note that the indications for surgical parathyroidectomy are not well defined, and there are no studies to define absolute biochemical criteria which would predict whether medical therapy will not be effective and surgery is required to control the hyperparathyroidism 1. However, the most recent study on the topic provides guidance on the appropriate use of imaging in the diagnosis and treatment of primary hyperparathyroidism, emphasizing the importance of precise preoperative localization of a single parathyroid adenoma to guide the surgical approach 1.

From the Research

Evaluation of Bilaterally Enlarged Parathyroid Gland on Neck Ultrasound

• The management approach for a patient with bilaterally enlarged parathyroid glands on neck ultrasound, normal serum calcium, and normal Parathyroid Hormone (PTH) levels is complex and requires careful consideration of various factors.
• According to 2, primary hyperparathyroidism is a common endocrine disorder of calcium metabolism characterized by hypercalcaemia and elevated or inappropriately normal concentrations of parathyroid hormone.
• However, in this case, the patient has normal serum calcium and PTH levels, which makes the diagnosis of primary hyperparathyroidism less likely.
• The study by 3 suggests that neck ultrasound is a useful tool for differentiating pathologic parathyroid glands from thyroid nodules, and that the morphologic patterns, echoic content, and vascular status of parathyroid glands are different from those of thyroid nodules.
• The management approach for this patient may involve monitoring of serum calcium concentrations and bone density, as recommended by 2 for patients who do not undergo parathyroid surgery.
• Additionally, the study by 4 suggests that preoperative calcium and PTH values are poor predictors of gland volume and multigland disease in primary hyperparathyroidism, which highlights the importance of careful evaluation and consideration of individual patient factors.

Diagnostic Considerations

• The diagnosis of hyperparathyroidism can be made using modern bio-assays that give direct measurements of parathormone (PTH), as stated by 5.
• However, in this case, the patient has normal PTH levels, which makes the diagnosis of hyperparathyroidism less likely.
• The study by 6 suggests that primary hyperparathyroidism may be revealed by biological abnormalities such as hypercalcemia, and can be accompanied by renal complications and/or osteoporosis.
• The differential diagnosis of primary hyperparathyroidism includes familial hypocalciuric hypercalcemia (FHH), a dominant autosomal disease that impairs parathyroid cell sensitivity to calcemia elevation, as discussed by 6.

Imaging and Localization

• Neck ultrasound is a widely used and accessible operator-dependent technique that helps characterize thyroid nodules and pathologic parathyroid glands, as stated by 3.
• The study by 5 suggests that various methods are currently available for pre-operative localization of pathological parathyroid glands, including ultrasound, CT, MRI, and MIBI scintigraphy.
• However, no radiological method is available to localize pathological glands in 100% of cases, and the surgeon is usually satisfied when two different methods are positive and in concordance, as discussed by 5.