Edwards Patton Dilly syndrome
Overview
A rare syndrome characterized mainly by deafness, kidney disease and increased parathyroid activity.
Symptoms
* Deafness * Kidney disease * Hyperparathyroidism * Parathyroid gland abnormalities * High blood calcium levels
Causes
Hyperparathyroidism may be primary or secondary. In primary hyperparathyroidism, one or more of the parathyroid glands enlarges, increasing PTH secretion and elevating serum calcium levels. The most common cause is a single adenoma. Other causes include a genetic disorder or multiple endocrine neoplasia. Primary hyperparathyroidism usually occurs between ages 30 and 50 but can also occur in children and the elderly. It affects two to three times more females than males. It’s a common disorder, affecting 1 in 1,000 people. In secondary hyperparathyroidism, excessive compensatory production of PTH stems from a hypocalcemia-producing abnormality outside the parathyroid gland, which causes a resistance to the metabolic action of PTH. Some hypocalcemia-producing abnormalities are chronic renal failure, renal absorption disorders, vitamin D deficiency (especially in the housebound elderly), or osteomalacia due to phenytoin or laxative abuse.
Treatment
Treatment varies, depending on the cause of the disease. Treatment of primary hyperparathyroidism may include surgery to remove the adenoma or, depending on the extent of hyperplasia, all but half of one gland (the remaining part of the gland is necessary to maintain normal PTH levels). Surgery may relieve bone pain within 3 days. However, renal damage may be irreversible. Preoperatively — or if surgery isn’t feasible or necessary — other treatments can decrease calcium levels. These include forcing fluids; limiting dietary intake of calcium; promoting sodium and calcium excretion through forced diuresis using normal saline solution (up to 6 L in life-threatening circumstances), furosemide, or ethacrynic acid; and administering oral sodium or potassium phosphate, subcutaneous calcitonin, I.V. plicamycin, or I.V. biphosphonates. Therapy for potential postoperative magnesium and phosphate deficiencies includes I.V. administration of magnesium and phosphate, or sodium phosphate solution given orally or by retention enema. In addition, during the first 4 to 5 days after surgery, when serum calcium falls to low normal levels, supplemental calcium may be necessary; vitamin D or calcitriol may also be used to raise serum calcium levels. Treatment of secondary hyperparathyroidism must correct the underlying cause of parathyroid hypertrophy. Vitamin D therapy or, in the patient with renal disease, administration of an oral calcium preparation (calcium acetate, if possible) for hyperphosphatemia, are typically used, although surgical excision may be necessary. In the patient with renal failure, dialysis is necessary to lower calcium levels and may have to continue for the remainder of the patient’s life. In the patient with chronic secondary hyperparathyroidism, the enlarged glands may not revert to normal size and function even after calcium levels have been controlled.