Four pathologic parathyroids (two patients) were not detected by the three imaging modalities probably due to their small size and weight (less than 10 mm and 0.1 g), an uncommon histological characteristic (one case of oncocytic micro-adenoma), and patient biological profiles (slight PTH increase (83 pg/mL) and subnormal calcemia (2.60 mmol/L) in one case, and moderate PTH increase (102 pg/mL) and vitamin D insufficiency (21 ng/mL) in the other one). This evidence concerns the gene PTH and vitamin D deficiency.