PTH and hyperphosphatemia: However, guidelines set by the Japanese society for dialysis therapy (JSDT) recommend that patients with severe hyperparathyroidism (persistent serum levels of intact PTH >500 pg/mL), accompanied with hypercalcemia (serum calcium >10.0 mg/dL) and/or hyperphosphatemia (serum phosphate >6.0 mg/dL) refractory to medical therapy should receive PTX [8].