Treatment strategy of end stage renal disease-related hyperparathyroidism before, during, and after the era of calcimimetics

Intact parathyroid hormone levels localize causative glands in persistent or recurrent renal hyperparathyroidism: A retrospective cohort study

Persistent or recurrent renal hyperparathyroidism may occur after total parathyroidectomy and transcervical thymectomy with forearm autograft under continuous stimulation due to uremia. Parathyroid hormone (PTH) levels may reflect persistent or recurrent renal hyperparathyroidism because of the enlarged autografted parathyroid glands in the forearm or remnant parathyroid glands in the neck or mediastinum. Detailed imaging requires predictive localization of causative parathyroid glands. Casanova and simplified Casanova tests may be convenient. However, these methods require avascularization of the autografted forearm for >10 min with a tourniquet or Esmarch. The heavy pressure during avascularization can be incredibly painful and result in nerve damage. An easier method that minimizes the burden on patients in addition to predicting the localization of causative parathyroid glands was developed in this study. Ninety patients who underwent successful re-parathyroidectomy for persistent or recurrent renal hyperparathyroidism after parathyroidectomy between January 2000 and July 2019 were classified according to the localization of causative parathyroid glands (63 and 27 patients in the autografted forearm and the neck or mediastinum groups, respectively). Preoperatively, intact PTH levels were measured from bilateral forearm blood samples following a 5-min avascularization of the autografted forearm. Cutoff values of the intact PTH ratio (intact PTH level obtained from the non-autografted forearm before re-parathyroidectomy/intact PTH level obtained from the autografted forearm before re-parathyroidectomy) were investigated with receiver operating characteristic curves to localize the causative parathyroid glands. Intact PTH ratios of <0.310 with an area under the curve (AUC) of 0.913 (95% confidence interval [CI]: 0.856–0.970; P < 0.001) and >0.859 with an AUC 0.744 (95% CI: 0.587–0.901; P = 0.013) could predict causative parathyroid glands in the autografted forearm and the neck or mediastinum with diagnostic accuracies of 81.1% and 83.3%, respectively. Therefore, we propose that the intact PTH ratio is useful for predicting the localization of causative parathyroid glands for re-parathyroidectomy.

Being elderly is not a contraindication of parathyroidectomy for renal hyperparathyroidism and chronic kidney disease-mineral and bone disorder

BACKGROUND

Chronic kidney disease-mineral and bone disorder (CKD-MBD) has more influence in the elderly. Parathyroidectomy remains the golden standard for this situation but has tended to be excluded for older patients for many reasons. This study aimed to evaluate the efficacy and safety of the surgery in the elderly population.

METHODS

156 patients were included and arranged into younger (≦65 years of age, n = 139) and elderly (>65 years of age, n = 17) groups. The change of bone mineral density (BMD) data, recovery potential {[(postoperative BMD) - (preoperative BMD)]/(preoperative BMD) ∗ 100%}, surgical successful rate and related complications were collected.

RESULTS

Both groups exhibited significant postoperative improvement on the BMD results. The recovery potential of the elderly was not lower than the younger group. High success rate and none of persistent vocal palsy, hypocalcemia or any sequela were also observed in the elderly.

CONCLUSIONS

Parathyroidectomy is an effective and safe intervention for the CKD-MBD in the elderly.

Long-term outcomes and management considerations after parathyroidectomy in the dialysis patient

Parathyroidectomy (PTX) remains an important intervention for dialysis patients with poorly controlled secondary hyperparathyroidism (SHPT), though there are only retrospective and observational data that show a mortality benefit to this procedure. Potential consequences that we seek to avoid after PTX include persistent or recurrent hyperparathyroidism, and parathyroid insufficiency. There is considerable subjectivity in defining and diagnosing these conditions, given that we poorly understand the optimal PTH targets (particularly post PTX) needed to maintain bone and vascular health. While lowering PTH after PTX decreases bone turnover, long-term changes in bone activity have been poorly explored. High turnover bone disease, usually present at the time a PTX is considered, often swings to a state of low turnover in the setting of sufficiently low PTH levels. It remains unclear if all low bone turnover equate with disease. However, such changes in bone turnover appear to predispose to vascular calcification, with positive calcium balance after PTX being a potential contributor. We know little of how the post-PTX state resets calcium balance, how calcium and VDRA requirements change or what kind of adjustments are needed to avoid calcium loading. The current consensus cautions against excessive reduction of PTH although there is insufficient evidence-based guidance regarding the management of chronic kidney disease - mineral bone disease (CKD-MBD) parameters in the post-PTX state. This article aims to compile existing research, provide an overview of current practice with regard to PTX and post-PTX chronic management. It highlights gaps and controversies and aims to re-orient the focus to clinically relevant contemporary priorities in CKD-MBD management after PTX.