Long-term (3 years) prognosis of parathyroid function in chronic dialysis patients after percutaneous ethanol injection therapy guided by colour Doppler ultrasonography

Abstract

Background. Secondary hyperparathyroidism (2HPT) is one of the most important complications in chronic dialysis (CD) patients. Percutaneous ethanol injection therapy (PEIT) of the parathyroid glands was introduced initially as an alternative treatment to parathyroidectomy and, with the technical progress of parathyroid imaging, it has now become a useful adjunct to medical therapy. The present study examined the possiblity of maintaining parathyroid function in the long term (3 years) after PEIT. Method. PEIT, guided by power-Doppler flow mapping, was performed in 33 CD patients with severe 2HPT, and all glands >5.0 mm in diameter were destroyed. Results. All patients showed a decline in the serum intact parathyroid hormone (i-PTH) concentration, on average from 695.5 to 248.0 pg/ml, after 1 year. After 3 years, the i-PTH concentration was controlled at <300 pg/ml in 85% of patients. The mean serum alkaline phosphatase (ALP) concentration also decreased from 322.7 to 154.4 IU/l after 1 year. In 76% of patients, ALP was maintained within the normal range (between 76 and 260 IU/l) at 3 years. Patients were classified into four groups according to the number of parathyroid glands detected by ultrasonography: one gland in group 1, two in group 2, three in group 3, and four in group 4. At 3 years after PEIT, i-PTH was controlled at <300 pg/ml in 100, 79, 83 and 82% of the patients in groups 1-4, respectively. Conclusions. It was possible to maintain long-term parathyroid function after PEIT in patients with 2HPT by using medical therapy, such as oral calcitriol pulse therapy and additional PEIT.