Multicenter study on parathyroidectomy (PTX) in Italy: preliminary results

Background When medical therapy is unable to achieve biochemical control of secondary hyperparathyroidism, parathyroidectomy (PTX) is indicated, fortunately in a minority of patients. Thus, data on PTX prevalence and biochemical control are limited and, in particular in Italy, date back to 1999. Methods We designed a prospective, observational and multicenter study to collect data from dialysis units distributed throughout the Italian regions. Clinical data were collected with a dedicated data sheet. Results From January to December 2010, 149 Centers serving a total of 12,515 patients provided data on 528 living PTX cases (PTX prevalence = 4.2%). Prevalence was higher in hemo- than in peritoneal dialysis (4.5 vs. 1.9%, X-2 = 21.52; p < 0.001), with non-significant regional differences (range 0.8-7.4%). PTX patients were younger (57.6 +/- 12.5 vs. 67.1 +/- 14.5 years; p < 0.001), more frequently female (56 vs. 38%, X-2 = 68.05, p < 0.001) and had been on dialysis for a longer time (14.63 +/- 8.37 vs. 4.8 +/- 6.0 years, p < 0.001) compared to the 11,987 who did not undergo neck surgery. Median time since surgery was 6.0 years (3.0-9.0; 50%, IQR). The most frequent type of surgery was subtotal PTX (sPTX = 55.0%), significantly higher than total PTX (tPTX = 38.7%) or total PTX plus auto-transplantation (aPTX = 6.3%) (X-2 = 5.18; Bonferroni post-hoc test, sPTX vs. tPTX + aPTX = p < 0.05). As for parathyroid hormone (PTH), calcium and phosphate control, cases targeting the KDOQI ranges were 18, 50.1 and 54.4%, respectively. The most prevalent biochemical condition was low PTH (62.7%). Conclusion PTX prevalence in Italy is stable compared to previous observations, is higher in hemodialysis than in peritoneal dialysis and results in a suboptimal biochemical control.