Hypercalcemia secondary to persistent hyperparathyroidism in kidney transplant patients: analysis after a year with cinacalcet.
BACKGROUND
The most common cause of hypercalcemia in patients with transplanted kidneys is persistent hyperparathyroidism, which presents in 10%-30% of patients with functioning renal grafts. In these patients, the treatment of vitamin D-resistant hyperparathyroidism traditionally required parathyroidectomy. Calcimimetic agents represent a new therapeutic alternative; they inhibit parathyroid hormone (PTH) secretion, increasing the sensitivity of the calcium-sensitive receptor in the parathyroid gland. The objective of this study is to evaluate the efficacy of cinacalcet in renal transplant patients with persistent hyperparathyroidism.


METHODS
Cinacalcet 30 mg/day was prescribed to 17 renal transplant patients (6 women, 11 men) with a mean age of 49 years and hypercalcemia secondary to persistent hyperparathyroidism. The treatment started 58.17 ± 35.16 months posttransplant, with 1 year of follow-up.


RESULTS
Calcium in serum fell from 10.5 ± 0.74 to 9.4 ± 0.84 mg/dL (p<0.001), whereas phosphorous levels were not significantly altered. The fall in PTH was from 204.79 ± 78 to 148.55 ± 56 pg/mL (p<0.011). Kidney function remained stable, and immunosuppressant drug levels remained unchanged. The dose of cinacalcet was increased to 60 mg in 2 patients. No significant adverse effects were described, and none of the patients had to suspend the treatment.


CONCLUSIONS
Calcimimetic agents represent a therapeutic alternative in transplant patients with persistent hyperparathyroidism, as they correct hypercalcemia and reduce PTH levels with no adverse effects on kidney function. Prospective, controlled studies should be designed to evaluate the long-term effects and evolution after suspension of the treatment.
Guerra
Rita
R
Department of Nephrology, Hospital Insular de Gran Canaria, Las Palmas de Gran Canaria, Spain.
Auyanet
Ingrid
I
Fernández
Ernest J
EJ
Pérez
Miguel Ángel
MÁ
Bosch
Elvira
E
Ramírez
Ana
A
Suria
Santiago
S
Checa
María Dolores
MD
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D057966:Calcimimetic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D002118:Calcium / Q000097:blood; D000069449:Cinacalcet; D003404:Creatinine / Q000097:blood; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D006961:Hyperparathyroidism / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009281:Naphthalenes / Q000008:administration & dosage* / Q000009:adverse effects; D010281:Parathyroid Hormone / Q000097:blood; D010758:Phosphorus / Q000097:blood; D011446:Prospective Studies; D013030:Spain; D013997:Time Factors; D016896:Treatment Outcome
D015415:Biomarkers; D057966:Calcimimetic Agents; D007166:Immunosuppressive Agents; D009281:Naphthalenes; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010758:Phosphorus; D003404:Creatinine; D002118:Calcium; D000069449:Cinacalcet