Resolution of Secondary Hyperparathyroidism After Kidney Transplantation and the Effect on Graft Survival

The Effects of Parathyroidectomy vs Medical Treatments for Secondary Hyperparathyroidism in Patients Undergoing Dialysis: A Meta-Analysis

OBJECTIVE

The management of secondary hyperparathyroidism in patients undergoing dialysis is debated, with uncontrolled parathyroid hormone (PTH) levels becoming more common despite the expanded use of medical treatments like cinacalcet. This study examines the clinical benefits of parathyroidectomy vs medical treatment in reducing mortality and managing key laboratory parameters in patients undergoing dialysis.

METHODS

PubMed, Embase, Cochrane, Scopus, and Web of Science databases were searched for cohort studies or randomized controlled trials published before August 18, 2023. We included studies with comparative arms, specifically medical treatment vs surgical intervention. Patients with a history of kidney transplant were excluded. Outcomes were analyzed using hazard ratios (HRs) for mortality and weighted mean differences (WMD) for laboratory parameters.

RESULTS

Twenty-three studies involving 24 398 patients were analyzed. The pooled meta-analysis has shown a significant reduction in all-cause (HR, 0.47; 95% confidence interval [CI], 0.35-0.61) and cardiovascular mortality (HR, 0.58; 95% CI, 0.40-0.84) for parathyroidectomy vs medical treatments. Subgroup analysis showed that parathyroidectomy was associated with a greater reduction in mortality in patients with a PTH level over 585 pg/mL (HR, 0.37; 95% CI, 0.24-0.58). No mortality difference was found when all patients in the medical group received cinacalcet alongside standard medical treatment (HR, 1.02; 95% CI, 0.49-2.11). Parathyroidectomy also led to a larger decrease in PTH (WMD, 1078 pg/mL; 95% CI, 587-1569), calcium (WMD, 0.86 mg/dL; 95% CI, 0.43-1.28), and phosphate (WMD, 0.74 mg/dL; 95% CI, 0.32-1.16).

CONCLUSION

Parathyroidectomy may offer a survival advantage compared to medical management in patients with severe secondary hyperparathyroidism.

Retracting the thyroid matters: Who develops asymptomatic transient thyrotoxicosis after parathyroidectomy

BACKGROUND

Hyperthyroidism after parathyroidectomy is not a well-understood complication. We sought to determine the incidence and risk factors of hyperthyroidism after parathyroidectomy.

MATERIALS AND METHODS

This is a prospective study of 91 patients undergoing parathyroidectomy. Pre- and post-operative thyroid-stimulating hormone(TSH) and free thyroxine(T4) levels at two-week follow-ups were collected. Bivariate analyses were conducted to compare demographics, laboratory results, and intraoperative findings between patients with normal and suppressed post-parathyroidectomy TSH.

RESULTS

Twenty-two(24.2 ​%) patients had suppressed TSH after parathyroidectomy and 2(2.2 ​%) reported symptoms of hyperthyroidism. All hyperthyroidism resolved within 6 weeks. No patients required medical treatment. Compared to the normal TSH group, the suppressed TSH group had significantly more bilateral explorations(91.0 ​% vs. 58.0 ​%, p ​= ​0.006), and superior parathyroid resections(95.5 ​% vs. 65.2 ​%, p ​= ​0.006).

CONCLUSION

Transient hyperthyroidism is common following parathyroidectomy, which is likely associated with intraoperative thyroid manipulation. Gentle retraction of thyroid glands in parathyroidectomy is warranted, especially during superior parathyroid gland resection.

Feasibility of an Online Patient-Driven International Parathyroid Registry

INTRODUCTION

Traditional parathyroid registries are labor-intensive and do not always capture long-term follow-up data. This study aimed to develop a patient-driven international parathyroid registry and leverage community connections to improve patient-centered care for hyperparathyroidism.

METHODS

An anonymous voluntary online survey was developed using Qualtrics and posted in an international patient and advocate-run social media group affiliated with over 11,700 members. The survey was developed from a literature review, expert opinion, and discussion with the social media group managers. It consists of seven sections: patient demographics, past medical history, preoperative symptoms, laboratory evaluation, preoperative imaging studies, operative findings, and operative outcomes.

RESULTS

From July 30, 2022, to October 1, 2022, 89 complete responses were received. Participants were from 12 countries, mostly (82.0%) from the United States across 31 states. Most participants were female (91.4%), White (96.7%) with a mean (±standard deviation) age of 58 ± 12 y. The most common preoperative symptoms were bone or joint pain (84.3%) and neuropsychiatric symptoms: including fatigue (82.0%), brain fog (79.8%), memory loss (79.8%), and difficulty with concentration (75.3%). The median (interquartile range) length from symptom onset to diagnosis was 40.0 (6.8-100.5) mo. Seventy-one percent of participants had elevated preoperative serum calcium, and 73.2% had elevated preoperative parathyroid hormone. All participants obtained preoperative imaging studies (88.4% ultrasound, 86.0% sestabimi scan, and 45.3% computed tomography). Among them, 48.8% of participants received two, and 34.9% had three imaging studies. The median (interquartile range) time from diagnosis to surgical intervention was 3 (2-9) mo. Twenty-two percent of participants traveled to different cities for surgical intervention. Forty-seven percent of participants underwent outpatient parathyroidectomy. Eighty-four percent of participants reported improved symptoms after parathyroidectomy, 12.4% required oral calcium supplementation for more than 6 mo, 32.6% experienced transient hoarseness after parathyroidectomy, and 14.6% required reoperation after initial parathyroidectomy.

CONCLUSIONS

This international online parathyroid registry provides a valuable collection of patient-entered clinical outcomes. The high number of responses over 10 wk demonstrates that participants were willing to be involved in research on their disease. The creation of this registry allows global participation and is feasible for future studies in hyperparathyroidism.

Pre-Transplant Hyperparathyroidism and Graft or Patient Outcomes After Kidney Transplantation

The impact of pre-transplant parathyroid hormone (PTH) levels on early or long-term kidney function after kidney transplantation is subject of debate. We assessed whether severe hyperparathyroidism is associated with delayed graft function (DGF), death-censored graft failure (DCGF), or all-cause mortality. In this single-center cohort study, we studied the relationship between PTH and other parameters related to bone and mineral metabolism, including serum alkaline phosphatase (ALP) at time of transplantation with the subsequent risk of DGF, DCGF and all-cause mortality using multivariable logistic and Cox regression analyses. In 1,576 kidney transplant recipients (51.6 ± 14.0 years, 57.3% male), severe hyperparathyroidism characterized by pre-transplant PTH ≥771 pg/mL (>9 times the upper limit) was present in 121 patients. During 5.2 [0.2-30.0] years follow-up, 278 (15.7%) patients developed DGF, 150 (9.9%) DCGF and 432 (28.6%) died. A higher pre-transplant PTH was not associated with DGF (HR 1.06 [0.90-1.25]), DCGF (HR 0.98 [0.87-1.13]), or all-cause mortality (HR 1.02 [0.93-1.11]). Results were consistent in sensitivity analyses. The same applied to other parameters related to bone and mineral metabolism, including ALP. Severe pre-transplant hyperparathyroidism was not associated with an increased risk of DGF, DCGF or all-cause mortality, not supporting the need of correction before kidney transplantation to improve graft or patient survival.