His laboratory investigations demonstrated low adjusted calcium (1.57 mmol/L, normal: 2.20-2.60), hyperphosphatemia (1.52 mmol/L, normal: 0.80-1.50), normal magnesium level, mild hypokalemia (3.3mmol/L, normal: 3.5-5.3), normal thyroid function tests, high parathyroid hormone level (129 pg/mL, normal: 15-65), normal 25-hydroxyvitamin D (55ng/mL) and normal serum creatinine. This evidence concerns the gene PTH and hyperphosphatemia.