Renal osteodystrophy is often called the “silent crippler” because symptoms do not occur until a patient has been on dialysis for a few years. Typical symptoms can be:
Early indicators of renal osteodystrophy include high phosphorus and/or high PTH levels, red eyes, itching and sores from calcium-phosphorus deposits.
Children with kidney disease can be especially affected by renal osteodystrophy because their bones are still growing.
To diagnose renal osteodystrophy, your doctor may take a sample of your blood to measure levels of calcium, phosphorus, PTH, and calcitriol. The doctor may perform a bone biopsy to see how dense your bones are. A bone biopsy is done under local anesthesia and involves removing a small sample of bone from the hip and analyzing it under a microscope. Determining the cause of renal osteodystrophy helps the doctor decide on a course of treatment.
Controlling PTH levels prevents calcium from being withdrawn from the bones. Usually, overactive parathyroid glands are controllable with a change in diet, dialysis treatment, or medication. The drug cinacalcet hydrochloride (Sensipar), approved by the Food and Drug Administration in 2004, lowers PTH levels by imitating calcium. If PTH levels can't be controlled, the parathyroid glands may need to be removed surgically.
If your kidneys aren't making adequate amounts of calcitriol, you can take synthetic calcitriol as a pill or in an injectable form. Your doctor may prescribe a calcium supplement in addition to calcitriol.
Renal osteodystrophy can also be treated with changes in diet. Reducing dietary intake of phosphorus is one of the most important steps in preventing bone disease. Almost all foods contain phosphorus, but it's especially high in milk, cheese, dried beans, peas, nuts, and peanut butter. Limit drinks such as cocoa, dark sodas, and beer. Often, medications such as calcium carbonate (Tums), calcium acetate (PhosLo), sevelamer hydrochloride (Renagel), or lanthanum carbonate (Fosrenol) are prescribed with meals and snacks to bind phosphorus in the bowel. These decrease the absorption of phosphorus into the blood. Be sure your phosphate binder is aluminum-free because aluminum can be toxic and cause anemia. A renal dietitian can help develop a dietary plan to control phosphorus levels in the blood.
Exercise has been found to increase bone strength in some patients. It's important, however, to consult a doctor or health care professional before beginning any exercise program.
A good treatment program, including proper attention to dialysis, diet, and medications, can improve your body's ability to repair bones damaged by renal osteodystrophy.