As expected, PTH postoperative levels were significantly lower in patients with unintentional parathyroidectomy (18.3 ± 18.5 vs. 30.3 ± 21, pg/mL, p < 0.001), with a significant higher incidence of postoperative biochemical hypocalcemia (44.4% vs. 35.5%, p = 0.042), and the PTH ratio was significantly lower in patients with IP, suggesting a greater reduction in PTH levels as a consequence of IP. The gene discussed is PTH; the disease is incontinentia pigmenti.