The classic mnemonic is stones, bones, groans, and moans: kidney stones, aching bones, abdominal groans (pain), and neuropsychiatric moans. The most common presenting symptoms prior to routine lab testing were nephrolithiasis and pathologic fractures or bone pain. Due to current routine laboratory testing, most patients diagnosed with hypercalcemia are asymptomatic or mildly symptomatic.

Nephrolithiasis in about 8 % of cases (most commonly men under age 60), nephrocalcinosis in <5 % of cases, polyuria, polydipsia, and hypertension related to renal disease.

Constipation, nausea, vomiting, heartburn, and abdominal pain.

Fatigue, depressed mood, difficulty concentrating, impaired memory, anxiety, sleep disturbance, proximal muscle weakness, and psychomotor symptoms. Stupor and coma may be found in cases of extreme hypercalcemia (serum calcium >14 mg/dL) or in the elderly.

Postmenopausal women.

Exposure to low-dose therapeutic ionizing radiation, family history of hyperparathyroidism, and lithium therapy for bipolar disorder.

Hyperparathyroidism occurs in a number of inherited diseases, such as MEN-1, MEN-2A, familial isolated hyperparathyroidism, and hyperparathyroidism-jaw tumor syndrome.

Patients with severe hypercalcemia may present with nausea, vomiting, confusion, and mental status changes. This is a medical emergency, as severe hypercalcemia can lead to cardiac arrhythmias and coma.

Physical exam findings are typically not useful in hyperparathyroidism, as the great majority of enlarged parathyroid glands are soft, less than 2 cm in diameter, and non-palpable. An anterior neck mass in a patient with hyperparathyroidism is most commonly a thyroid nodule but can represent a parathyroid carcinoma.

Facial twitch in response to tapping on the facial nerve, anterior to the external auditory canal. This reflects early tetany and is a sign of hypocalcemia that may arise after parathyroidectomy.

The combination of flexion of the wrist and metacarpophalangeal joints and extension of the digits following inflation of a blood pressure cuff around the arm to greater than systolic blood pressure. Similar to Chvostek’s sign, this marks early tetany due to hypocalcemia.

The T-score is a test of bone density. The T-score refers to the number of standard deviations below the average for a young adult at peak bone density. Normal bone has a T-score better than −1. Patients with osteopenia have scores between −1 and −2.5, whereas those with osteoporosis have a score less than −2.5.

There are four parathyroid glands, two superior and two inferior. The superior parathyroids develop from the 4th pharyngeal pouch and migrate in conjunction with the lateral anlage of the thyroid, which form the tubercle of Zuckerkandl on the posterolateral aspect of the thyroid. The superior parathyroid glands are very consistent in their location, with approximately 95 % being located adjacent to the tubercle of Zuckerkandl, posterior to the terminus of the recurrent laryngeal nerve. The inferior parathyroid glands develop from the 3rd pharyngeal pouch and migrate inferiorly in conjunction with the thymus. The inferior parathyroid glands are more variable in their location. About 65 % are located on the surface of the inferior aspect of the thyroid gland, with most of the remainder being found within the thyrothymic ligament or the thymus.

Ectopic superior parathyroid glands are most commonly found in posterior locations along the esophagus or prevertebral fascia and less commonly in undescended locations near the superior thyroid artery. Ectopic inferior glands may be located in the mediastinum or in the carotid sheath. Intrathyroidal parathyroid glands may be found in 1–4 % of humans. These are classically superior glands, though inferior glands may be partially intrathyroidal. Intrathyroidal parathyroid adenomas may be detected as hypoechoic nodules on ultrasound, and needle aspiration with cytology and/or PTH measurement within the aspirate may aid in the diagnosis. Up to 15 % of people may have more than four parathyroid glands.