PTH and Huntington disease: The syndrome of MBD was reflected by the degree of arterial calcification, which was significantly higher in HD than in controls; by significantly higher levels of parathyroid hormone (PTH) and osteocalcin in HD and KTR than in controls; by significantly higher bone ALP isoforms (Table 1) and higher ALP activity (Figure 2A) in HD or EKTR than in controls.