PTH and Marchiafava-Bignami disease: According to the Kidney Disease: Improving Global Outcomes (KDIGO) 2006 guidelines, CKD–MBD is defined as ‘‘a systemic disorder of mineral and bone metabolism due to CKD manifested by either one or a combination of the following: (a) abnormalities of calcium, phosphorus, PTH, or vitamin D metabolism; (b) abnormalities in bone turn-over, mineralization, volume, linear growth, or strength; or (c) vascular or other soft tissue calcification’’ [4].