PTH and hyperparathyroidism: Hyperparathyroidism resistant to calcimimetic administrationaSevere refractory hyperphosphatemiaSevere hyperparathyroidism in dialysis without response to medical treatmentCases of calciphylaxis with PTH levels above 500 pg/mL that do not rapidly respond to calcimimeticsComplications derived from SHPTbPrimary hyperparathyroidism in patients with CKD