PTH and hyperphosphatemia: The biochemical markers of SHPT demonstrate distinct patterns after kidney transplantation: PTH levels decrease significantly during the first 3 months and tend to stabilize at elevated levels after 1 year; low calcium levels tend to increase and stabilize at the higher end of the normal range within 6 months; phosphate decreases rapidly after transplant to within or below normal levels (413); and FGF23 levels decrease but appear persistently increased as an adaptive mechanism to hyperphosphatemia due to reduced kidney function (411).