Double-phase parathyroid 99mTc-Sestamibi scintigraphy in chronic haemodialysis patients: correlation with biochemical markers of parathyroid function

Abstract

99mTc-Sestamibi identifies the presence of hyperfunctioning autonomous parathyroid glands in patients with secondary hyperparathyroidism (SHP). The objectives of this study were: (i) to evaluate the interdependence between biochemical markers of SHP and 99mTc-Sestamibi uptake; and (ii) to determine whether 99mTc-Sestamibi uptake could be efficiently predicted by any combination of the former variables. Double-phase parathyroid 99mTc-Sestamibi uptake and total serum calcium, phosphorus, intact parathormone, 25-OH vitamin D and 1,25(OH) vitamin D determinations were performed simultaneously in 74 patients (36 female, 38 male) with SHP. Planar images of the neck and upper thorax were obtained in anterior view, 15 min (early phase) and 120 min (delayed phase) after the injection of 740 MBq of 99mTc-Sestamibi. In each patient, a final parathyroid/thyroid (P/T) activity index was obtained by adding the results of the P/T index of all parathyroid lesions. There was a significant correlation between intact parathormone levels and delayed 99mTc-Sestamibi uptake ( r=0.656; P<0.01). Of all the variables, intact parathormone was the only significant predictor of delayed 99Tc-Sestamibi uptake ( r=0.487; P<0.001). Calcium, phosphorus, vitamin D metabolites, age, gender, time spent on haemodialysis and cause of chronic renal failure displayed no significant correlation with 99mTc-Sestamibi uptake. It can be concluded that 99mTc-Sestamibi uptake is a potential predictor of parathyroid function in SHP patients. Hence, 99mTc-Sestamibi scintigraphy could be useful to assess parathyroid function and in the clinical follow-up of these patients.

Role of Preoperative Diagnostic Imaging Procedures in Secondary Hyperparathyroidism

“…However, it should be recognized that the rate of persistent or recurrent disease in this setting is as high as 10-30%, the main cause being incomplete localization of glands, suggesting that more caution is Fig. The study concludes that MIBI uptake accurately reflects PTH levels without external influences [4]. Normal double-phase parathyroid scintigraphy.…”

“…Imaging of the parathyroid glands has been used in the identification of solitary parathyroid adenomas, which is the most common finding in patients with primary HPT [1]. parathyroid scintigraphy [3][4][5][6][7][8][9][10][11][12][13][14][15][16] and ultrasound (US) [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32], have been assayed to establish their possible utility in SHP. Recently, preoperative non-invasive imaging tools, i.e.…”

Failed Switching off in the MIBI-Parathyroid Scintigraphy in a Dialyzed Patient with Secondary Hyperparathyroidism Responsive to Cinacalcet Therapy

“…In recent years, various techniques including ultrasound (US), CT, magnetic resonance and MIBI-scintigraphy have been used to localize better enlarged parathyroid glands in patients with SHPT, although MIBI scintigraphy appears to be the most specific in recurrent/persistent SHPT [3–5]. Calcimimetics have become available for the treatment of dialysis patients with insufficiently controlled SHTP as well as calcium and/or phosphate levels on conventional therapies.…”

“…Piga et al [18] stated that MIBI scans do not simply reveal parathyroid enlargement but rather identify hyperfunctioning parathyroid glands in patients with SHPT. Additional evidence that MIBI shows the functional status of parathyroids is found in the correlation between MIBI uptake and intact PTH in SHPT [19, 20]. Moreover, Torregrosa et al [21] demonstrated that high MIBI uptake is correlated with the G 2 /S (active growth) phase.…”

Dual-phase 99mTc-MIBI scintigraphy to assess calcimimetic effect in patients on haemodialysis with secondary hyperparathyroidism

“…However, the need for imaging in such patients is still debatable because of the low sensitivity in the detection of hyperplastic multiglandular disease. A comparison of morphological and functional data strongly suggests that 99m Tc-MIBI not only reveals parathyroid enlargement but can also identify the presence of hyperfunctioning parathyroid tissue [14]. This radiotracer has shown itself to be highly accurate in reflecting PTH levels without external influences [14], and has proved to be a useful tool in clinical management, allowing the physician to discriminate between patients who will respond to calcitriol treatment and those who will not [15,16].…”