What is the treatment?
Secondary hyperparathyroidismSecondary hyperparathyroidism - A condition where a disease outside of the parathyroid glands causes all of the parathyroid glands to become enlarged and hyperactive. Sestamibi scan- Nuclear medicine test where a small amount of radioactive material is injected into a vein and an X-ray is taken. is usually treated with medical therapy, and surgery is only performed if these fail. The improvements in medical therapy have reduced the need for surgery in patients with chronic kidney disease. A new type of drug called calcimimetics (such as cinacalcet or Sensipar) have improved the therapy for this disease. (see Alternatives to Surgery)
Medical therapy: The main treatments are vitamin D analogues, phosphate binders, and calcimimetics. Vitamin D analogues reduce parathyroid hormone (PTH) levels, but may also increase the blood calcium levels and may contribute to calciphylaxisCalciphylaxis - When calcium deposits in places like the fat or skin. This can lead to ulcers and necrosis (when the tissue dies).. Phosphate binders reduce blood phosphorous levels. Aluminum-based compounds are highly effective, but may decrease bone strength and are therefore generally not used. Calcium-containing phosphate binders are less powerful, but can increase the blood calcium levels and may lead to soft tissue, blood vessel and heart calcification. Newer calcium-free polymer agents may not raise the blood calcium levels as much. Calcimimetics are medications that attach to a receptor on parathyroid cells and increase the ability of the cells to recognize high calcium levels in the bloodstream so that less PTH is made. By causing less PTH to be made, calcimimetics decrease the amount of calcium in the bloodstream. Taking cinacalcet will not cure the disease process. It can only decrease parathyroid hormone secretion to a certain extent. Cinacalcet is FDA approved for treatment of secondary hyperparathyroidism. On average, patients with secondary hyperparathyroidism have a decrease in PTH levels by about 50%. Its main side effects are nausea and vomiting.
Medical treatment of secondary hyperparathyroidism fails in up to 25% of patients. Indications (reasons) for parathyroidectomy include high calcium and/or phosphorous levels in the blood which cannot be managed with dialysis or medical therapy, worsening bone density, intractable pruritus (itching), or calciphylaxisCalciphylaxis - When calcium deposits in places like the fat or skin. This can lead to ulcers and necrosis (when the tissue dies).. Since chronically elevated PTH levels may increase the risk of heart and stroke related death, surgery should also be considered for elevated PTH levels above 800 pg/ml (National Kidney Foundation Guidelies). Surgical options for the treatment of secondary hyperparathyroidism include subtotal parathyroidectomy or total parathyroidectomy with autotransplantationAutotransplantation - When a piece of parathyroid tissue is re-implanted in the muscle of the forearm or neck. This is usually done in cases of secondary hyperparathyroidism or re-operative parathyroid surgery..
Subtotal parathyroidectomy (removing 3 1/2 glands) and total parathyroidectomy (removing all four glands) with autotransplantation of parathyroid tissue have about the same rates of recurrent (3-40%) and persistent (5-25%) disease, postoperative hypocalcemia (2-73%), and improvement in symptoms (67-100%). 88-90 (see Special Cases: Re-operative Parathyroid Surgery) Subtotal parathyroidectomy and total parathyroidectomy with autotransplantation both leave behind a small amount of parathyroid tissue. The same process that caused the original parathyroid glands to become abnormal will cause the remaining parathyroid tissue to also become abnormal. Therefore, unless these patients have a kidney transplantation, they are at high risk for recurrent disease (5% to 80%). It is unclear if subtotal parathyroidectomy or total parathyroidectomy with autotransplantation is better for patients. Ultimately, you will decide with your surgeon which operation to have. Surgical skill and experience and proper patient selection appear to be more important to a successful outcome than which operation is performed. The advantages and disadvantages of these two surgical procedures are:
|Subtotal parathyroidectomy||Possible less postoperative hypocalcemia (low calcium levels)||Re-operating in the neck has higher risks (if the patient needs a second operation)|
|Total parathyroidectomy with autotransplantation||Reoperation has fewer risks because the parathyroid autotransplant is usually placed in the forearm and not the neck||Possible prolonged hypocalcemia (low calcium levels) while waiting for the autotransplant to work|