Clinical significance of parathyroid intervention on CKD-MBD management

The efficacy of cinacalcet combined with conventional therapy on bone and mineral metabolism in dialysis patients with secondary hyperparathyroidism: a meta-analysis

Cinacalcet, the first calcimimetic to be approved for the treatment of secondary hyperparathyroidism (SHPT) in the chronic kidney disease patients, offers a novel therapeutic approach to SHPT. The aim of this meta-analysis is to access the efficacy and safety of cinacalcet on bone and mineral metabolism disorders in the dialysis patients with SHPT. Randomized controlled trials on cinacalcet combined with vitamin D and/or phosphate binders in the dialysis patients with SHPT were identified in Pubmed, Sciencedirect, and the Cochrane library. Data were analyzed with RevMan software. We compared the proportion of patients achieving the biochemical targets recommended by the Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines and the incidence of adverse events between the cinacalcet and control groups. Six trials involving 2,548 patients were included. A greater proportion of patients in the cinacalcet group compared with the conventional group achieved the KDOQI targets. The relative risks (RRs) were parathyroid hormone (PTH) (RR = 3.51, 95 % CI: 2.38-5.17), calcium (RR = 2.04, 95 % CI: 1.76-2.37), phosphorus (RR = 1.15, 95 % CI: 0.83-1.60), and calcium-phosphorus product (Ca × P) (RR = 1.41, 95 % CI: 1.18-1.69), the number of patients simultaneously achieving the KDOQI targets for PTH + Ca × P was also greater (RR = 3.89, 95 % CI: 2.36-6.41), with p < 0.001 for each. The most common adverse events were nausea, vomiting, diarrhea, and hypocalcemia, which had a higher incidence in the cinacalcet group, but were usually mild to moderate in severity and transient. Compared with conventional therapy, treatment with cinacalcet results in more patients achieving KDOQI targets and offers an effective and safety therapeutic option for controlling mineral and bone disorders in the dialysis patients with SHPT.

Use of percutaneous ethanol injection therapy for recurrent secondary hyperparathyroidism after subtotal parathyroidectomy

We evaluated the efficacy of percutaneous ethanol injection therapy (PEIT) as a therapeutic option for recurrence of secondary hyperparathyroidism after subtotal parathyroidectomy in ESRD patients. Six patients underwent PEIT. A mean of 1.3 ± 0.8 ethanol injections was performed. Nodular volume was 1.5 ± 1.7 cm³, and 2.8 ± 2.8 cm³ of ethanol was injected per patient. After ethanol injection PTH decreased significantly (1897 ± 754 to 549 ± 863 pg/mL (P < .01)). There was also a reduction in serum calcium, phosphorus and calcium-phosphorus product. A positive and significant correlation was found between nodular volume with ethanol injected and time from parathyroidectomy. Only one patient required hospitalization due to severe hypocalcaemia. In other two cases, local discomfort and temporary mild dysphonia were registered. PEIT is an effective treatment to control recurrences of secondary hyperparathyroidism postsubtotal parathyroidectomy.

A haemodialysis patient with back pain: brown tumour as a cause of spinal cord compression under cinacalcet therapy

A 43-year-old haemodialysis patient was admitted to hospital because of paroxysmal pain in the upper abdominal region radiating to the back. Laboratory tests showed severe hyperparathyroidism [intact parathyroid hormone (iPTH) 69 pmol/L; reference range: 1.3-6.8 pmol/L], hypercalcaemia (2.79 mmol/L), hyperphosphataemia (1.6 mmol/L) and elevated serum total alkaline phosphatase (200 U/L). After developing a disturbed sensation and paraesthesia in both feet, epidural compression of the spinal cord was suspected. Magnetic resonance imaging showed a tumour that severely compressed the myelum of the thoracic spine. Histological investigation revealed a brown tumour or osteoclastoma, an erosive bony lesion caused by increased osteoclastic activity and peritrabecular fibrosis. A brown tumour is a benign tumour that is a rare complication of severe renal hyperparathyroidism. The brown tumour developed despite a 1-year treatment of the patient with cinacalcet, which, however, did not result in a major decrease in serum iPTH concentration (from 110 to 69 pmol/L: 37% reduction). Urgent decompressive neurosurgery and subtotal parathyroidectomy resulted in a complete recovery.