Parathyroid gland ultrasound patterns and biochemical findings after one-year cinacalcet treatment for advanced secondary hyperparathyroidism.
Cinacalcet efficacy is limited in severe secondary hyperparathyroidism (SHPT) and its effect on parathyroid gland (PTG) volume and morphology have not been sufficiently investigated. We evaluated the effect of cinacalcet treatment for one year on the laboratory parameters of calcium-phosphorus metabolism and PTG ultrasound (US) patterns in hemodialysis (HD) patients with severe SHPT and US results indicative of nodular hyperplasia. Thirteen HD patients with severe SHPT (intact parathyroid hormone >700 pg/mL), US/scintigraphic evidence of at least one PTG with a diameter >7 mm, and high surgical risk or refusal of surgery were included. The patients were treated with cinacalcet. The initial dose of 30 mg was increased up to 180 mg once daily. At baseline and after one year of cinacalcet treatment a neck US was performed, providing data on 22 parathyroid glands in eight patients. The mean diameter at baseline and at one year was 12.6 +/- 5.9 and 13.0 +/- 5.3 mm, respectively (P = 0.46). Similarly, the mean volume at baseline and at one year was 513.4 +/- 416.3 and 556.8 +/- 480.8 mm(3), respectively (P = 0.18). The US structural score remained unchanged in 16 parathyroid glands and increased in 6 (P < 0.03), while the vascular score remained unchanged in 16 parathyroid glands and decreased in 6 (P = 0.25). Thus it can be concluded that cinacalcet treatment for one year in HD patients with severe SHPT is not associated with significant changes in parathyroid gland US patterns.