[Disagreement between findings of 99mTc-MIBI and 99mTc-pertechnetate scintigraphy scans in patients with primary...

Sixty-two-year-old man was admitted to hospital for increased serum level of calcium (3.85 mmol/l) and incipient renal failure (urea 7.2 mmol/l, kreatinin 117 mumol/l). The reason of hypercalcaemia was intensive explored. Serum level of intact PTH was 383.6 pg/ml. We performed two-dimensional early and delayed (2 hours) scintigram after intravenous administration of 750 MBq 99mTc-sestamibi, i.e. double-phase technique. There was detected focus (diameter 20 mm) of increased sestamibi uptake with slow wash-out in distal part right thyroid lobe. Planar scintigraphy obtained after intravenous administration of 185 MBq 99mTc-pertechnetate detected focus of increased 99mTc-pertechnetate uptake in the same point too. Patient underwent right thyroid lobectomy. There was colloid nodular goiter. Under right thyroid lobe was detected spherical particle. This particle was ablated (diameter 20 mm, weight 4 gram). It was parathyroid adenoma. One month after ablation of parathyroid adenoma serum level of PTH was 23.1 pg/ml and serum level of calcium was 2.52 mmol/l. There was overlap of scintigraphy image of parathyroid adenoma under distal part of right thyroid lobe on 99mTc-sestamibi two-dimensional scintigram and scintigraphy image of hyperplastic node with increased activity in distal part of right thyroid lobe on 99mTc-pertechnetate two-dimensional scintigram.