In people with an inherited syndrome, a changed (mutated) gene is passed down through the family. You only need to get the gene from one parent to develop the condition.
In MEN I, problems in the parathyroid glands occur, as well as tumors in the pituitary gland and pancreas.
In MEN IIA, overactivity of the parathyroid glands occurs, along with tumors in the adrenal or thyroid gland.
Parathyroid hyperplasia is more likely to occur as an effect of other medical conditions than from a problem of the parathyroid glands. The most common conditions that can cause parathyroid hyperplasia are chronic kidney disease and chronic vitamin D deficiency.
Blood tests will be done to check calcium, phosphorus, magnesium, PTH, and vitamin D levels. A 24-hour urine test may be done to determine how much calcium is being filtered out of the body into the urine.
Bone x-rays and a bone density test (DXA) can help detect fractures, bone loss, and bone softening.
Surgery is the preferred treatment. Usually 3 1/2 glands are removed. The remaining tissue may be implanted in the forearm so a doctor can easily operate on it if symptoms come back. This tissue will also help the body control calcium levels.
Increased calcium levels persist or return about 20% of the time after surgery. Surgery can sometimes cause hypoparathyroidism, which makes the blood calcium too low.
Parathyroid hyperplasia can cause hyperparathyroidism, which leads to an increase in blood calcium levels.
Patients with a family history of the MEN syndromes may want to have genetic screening to check for the defective gene. Those who have the defective gene may have routine screening tests to detect any early symptoms.
Bringhurst FR, Demay MB, Kronenberg HM. Disorders of mineral metabolism. In: Kronenberg HM, Schlomo M, Polansky KS, Larsen PR, eds. Williams Textbook of Endocrinology. 11th ed. St. Louis, MO: WB Saunders; 2008:chap 27.
Wysolmerski JJ, Insogna KL. The parathyroid glands, hypercalcemia, and hypocalcemia. In: Kronenberg HM, Schlomo M, Polansky KS, Larsen PR, eds. Williams Textbook of Endocrinology. 11th ed. St. Louis, MO: WB Saunders; 2008:chap 266.
Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.