Hyperparathyroidism but a negative sestamibi scan: a clinical dilemma

Usefulness of 99mTc-SESTAMIBI Scintigraphy in Persistent Hyperparathyroidism after Kidney Transplant

Purpose

^99mTc-labeled sestamibi scintigraphy combined with single-photon emission computed tomography (SPECT) has a high positive predictive value for localizing hyperfunctioning parathyroid lesions in primary hyperparathyroidism (pHPT) but relatively low sensitivity and specificity in secondary hyperparathyroidism (sHPT) and tertiary hyperparathyroidism (tHPT). The purpose of this study is to investigate the usefulness of ^99mTc-sestamibi scintigraphy in persistent hyperparathyroidism after kidney transplant (KT).

Methods

Retrospectively evaluated 50 patients who received parathyroidectomy after KT at a single medical center. The parathyroid lesion with the highest sestamibi uptake intensity of a patient was graded from 0 to 3. Uptake intensity was analyzed in correlation with parathyroid hormone (PTH), calcium, ionized calcium, phosphorus, and vitamin D.

Results

Per-patient analysis, 43 patients had hyperplasia, 6 patients had adenomas, and 1 patient had a carcinoma. Only 3 patients with hyperplasia did not demonstrate any sestamibi uptake in the parathyroid scans. Out of the 148 pathologically confirmed parathyroid lesions, SPECT/CT images were able to identify 89 lesions (60%) and planar images of 71 lesions (48%). The average of sestamibi uptake intensity was mild at grade 1.6. Uptake intensity showed a positive correlation with parathyroid hormone (PTH) level but not with phosphorus, calcium, ionized calcium, or vitamin D levels. The largest lesion showed a high positive predictive value, especially in lesions with a diameter over 1.0 cm.

Conclusions

Regardless of relatively low and less discrete uptake in KT patients, it well depicts the largest and the most hyperfunctioning lesion.

Predictors of multiglandular disease in primary hyperparathyroidism

Background

Primary hyperparathyroidism (pHPT) is caused by single- or multiglandular disease (MGD). Patients with MGD have an increased risk of complications at surgery and for persistence and recurrence after surgery. The study evaluated whether preoperative clinical and biochemical characteristics could predict MGD in patients with pHPT.

Methods

We retrospectively evaluated patients operated 1989–2013 for first-time, non-hereditary pHPT. MGD was defined in patients with more than one pathological gland excised at surgery or with persistent hypercalcemia after the excision of a single pathological parathyroid gland, confirmed by histopathology. Clinical and biochemical variables were compared in patients with single- and multiglandular disease. Logistic regression was used to identify variables predicting MGD, yielding odds ratios (OR) with 95% confidence intervals (CI).

Results

There were 707 patients, of which 79 (11%) had MGD. Patients with MGD were more likely to have negative sestamibi scintigraphy than patients with single-gland disease, 15 of 49 (31%) vs. 70 of 402 (17%; p = 0.03), to suffer from diabetes (12 of 74, 16%) vs. 45 out of 626 patients (7.2%; p < 0.01) and had lower preoperative levels of urinary calcium (3.80 vs. 4.44 mmol/L; p = 0.04). Multivariable analysis identified negative scintigraphy (OR 2.42; 95% CI 1.18 to 4.79), diabetes (OR 2.75; 95% CI 1.31 to 4.97) and elevated levels of osteocalcin (OR 3.79, 95% CI: 1.75 to 8.21) as predictors of MGD.

Conclusion

Negative sestamibi scintigraphy, diabetes and elevated osteocalcin levels were predictors of MGD.

Quality of Life After Surgery or Surveillance for Asymptomatic Primary Hyperparathyroidism: A Meta-Analysis of Randomized Controlled Trials

A number of studies have investigated the effects of surgery on symptoms and quality of life in patients with hyperparathyroidism. However, the results are inconsistent. We conducted this meta-analysis to quantitatively assess changes in quality of life among patients with asymptomatic primary hyperparathyroidism. Different databases were searched for randomized controlled trials comparing surgery with surveillance. Quality of life was measured by the Short Form-36 general health survey. The pooled random-effects estimates of standardized mean difference (SMD) and 95% confidence intervals (CIs) were calculated. Three trials involving 294 participants were included. At 1 year, patients undergoing parathyroidectomy had significantly better physical role functioning (SMD, 0.31; 95% CI 0.04-0.57; P = 0.02) and emotional role functioning (SMD, 0.29; 95% CI 0.02-0.55; P = 0.03). At 2 years, the surgery group had significantly better emotional role functioning (SMD, 0.35; 95% CI 0.02-0.67; P = 0.04) than the surveillance group. Furthermore, compared with baseline, emotional role functioning improved after surgery (SMD, 0.31; 95% CI 0.02-0.60; P = 0.04), whereas emotional role functioning tended to get worse in patients assigned to medical surveillance (SMD, -0.27; 95% CI -0.55 to 0.02; P = 0.07). Although Short Form-36 is a generic instrument, our results suggest that parathyroidectomy may be associated with better quality of life, especially in the emotional aspects of well-being.