Challenges and controversies in the surgical management of uremic hyperparathyroidism: A systematic review

Does race impact outcomes after parathyroidectomy for secondary and tertiary hyperparathyroidism?

BACKGROUND

Racial disparities in care exist for diseases with heterogeneous treatment guidelines. The impact of these disparities on outcomes after parathyroidectomy for secondary(2HPT) and tertiary hyperparathyroidism(3HPT) was explored.

METHODS

The 2015-2019 NSQIP datasets were used. Patients who underwent parathyroidectomy for 2HPT and 3HPT were identified and analyzed separately. Patients were stratified by race (white vs. non-white); demographics, comorbidities, and outcomes were compared. Studied outcomes included 30-day morbidity, mortality, unplanned reoperation, readmission, and postoperative length of stay(LOS).

RESULTS

There were 1,150 patients with 2HPT and 262 with 3HPT. For 2HPT, 65.5% were non-white; morbidity, reoperation, and prolonged LOS(>3days) occurred disproportionately more often in non-white patients. Non-white race was independently associated with morbidity; higher ASA class and alkaline phosphatase levels were associated with prolonged LOS. For 3HPT, 53.1% were non-white; a prolonged LOS(>1day) occurred disproportionately more often in non-white patients. Higher alkaline phosphatase levels were independently associated with prolonged LOS.

CONCLUSION

Race and markers of advanced disease negatively impact outcomes after parathyroidectomy for 2HPT and 3HPT. Attention to racial disparities and earlier referral may positively impact outcomes.

18F-Fluorocholine PET/CT Compared with Current Imaging Procedures for Preoperative Localization of Hyperfunctioning Parathyroids in Patients with Chronic Kidney Disease

Hyperparathyroidism (HPT) in patients with chronic kidney disease (CKD) includes secondary (sHPT) and tertiary hyperparathyroidism (tHPT). Considering that the role of preoperative imaging in the clinical setting is controversial, in the present study we have retrospectively compared pre-surgical diagnostic performances of ¹⁸F-Fluorocholine (¹⁸F-FCH) PET/CT, cervical ultrasonography (US), parathyroid scintigraphy, and 4D-CT in a group of 30 patients with CKD and HPT (18/12 sHPT/tHPT), 21 CKD G5 including 18 in dialysis, and 9 kidney transplant recipients. All patients underwent ¹⁸F-FCH, and 22 had cervical US, 12 had parathyroid scintigraphy, and 11 had 4D-CT. Histopathology was the gold standard. Seventy-four parathyroids were removed: 65 hyperplasia, 6 adenomas, and 3 normal glands. In the whole population, in a per gland analysis, ¹⁸F-FCH PET/CT was significantly more sensitive and accurate (72%, 71%) than neck US (25%, 43%), parathyroid scintigraphy (35%, 47%), and 4D-CT (40%, 47%). The specificity of ¹⁸F-FCH PET/CT (69%) was lower than that of neck US (95%) and parathyroid scintigraphy (90%), without, however, achieving significance. ¹⁸F-FCH PET/CT was more accurate than all other diagnostic techniques when sHPT and tHPT patients were considered separately. ¹⁸F-FCH PET/CT sensitivity was significantly higher in tHPT (88%) than in sHPT (66%). Three ectopic hyperfunctioning glands (in three different patients) were all detected by ¹⁸F-FCH PET/CT, two by parathyroid scintigraphy, and none by cervical US and 4D-CT. Our study confirms that ¹⁸F-FCH PET/CT is an effective preoperative imaging option in patients with CKD and HPT. These findings may be of greater importance in patients with tHPT (who could benefit from minimally invasive parathyroidectomy) than in patients with sHPT, who often undergo bilateral cervicotomy. In these cases, preoperative ¹⁸F-FCH PET/CT may be helpful in locating ectopic glands and may guide the surgical choice for gland preservation.

Black patients are more likely to undergo parathyroidectomy for secondary hyperparathyroidism

BACKGROUND

Prior studies have demonstrated racial disparities in the severity of secondary hyperparathyroidism among dialysis patients. Our primary objective was to study the racial and socioeconomic differences in the timing and likelihood of parathyroidectomy in patients with secondary hyperparathyroidism.

METHODS

We used the United States Renal Data System to identify 634,428 adult (age ≥18) patients who were on maintenance dialysis between 2006 and 2016 with Medicare as their primary payor. Adjusted multivariable Cox regression was performed to quantify the differences in parathyroidectomy by race.

RESULTS

Of this cohort, 27.3% (173,267) were of Black race. Compared to 15.4% of White patients, 23.1% of Black patients lived in a neighborhood that was below a predefined poverty level (P < .001). The cumulative incidence of parathyroidectomy at 10 years after dialysis initiation was 8.8% among Black patients compared to 4.3% among White patients (P < .001). On univariable analysis, Black patients were more likely to undergo parathyroidectomy (adjusted hazard ratio = 1.83; 95% confidence interval, 1.74-1.93). This association persisted after adjusting for age, sex, cause of end-stage renal disease, body mass index, comorbidities, dialysis modality, and poverty level (adjusted hazard ratio = 1.35; 95% confidence interval, 1.27-1.43). Therefore, patient characteristics and socioeconomic status explained 26% of the association between race and likelihood of parathyroidectomy.

CONCLUSION

Black patients with secondary hyperparathyroidism due to end-stage renal disease are more likely to undergo parathyroidectomy with shorter intervals between dialysis initiation and parathyroidectomy. This association is only partially explained by patient characteristics and socioeconomic factors.

Parathyroidectomy for dialysis patients in the era of calcimimetics: The surgeons' point of view

Calcimimetics is a new drug for lowering serum parathyroid hormone (PTH), calcium and phosphate in patients with hyperparathyroidism (HPT) on long-term dialysis. It became available on market in 2006. The impact of calcimimetics on the treatment by parathyroidectomy (PTx) was reviewed from the surgeons' point of view. Cure of renal HPT by calcimimetics is not feasible, but calcimimetics can improve preoperative cardiac ventricle ejection fractions by lowering serum PTH. Heart failure is not necessarily a contraindication for PTx. PTx should be done before irreversible organ damage occurs. Limb gangrenes is an ominous sign and should be prevented by frequent checkup for peripheral arterial circulation. The impact of renal osteodystrophy on the quality of life and as indirect cause of mortality deserves more attention in patients with renal HPT. Delayed referral to PTx leads to more complicated patients. A consensus between nephrologists and surgeons about propitious timing for PTx is necessary. Future prospect on the surgical treatment of renal HPT is proposed. Supplemental figure; http://links.lww.com/ASAIO/A782.

Hiperparatiroidismo primario por adenoma paratiroideo doble con glándulas paratiroides eutópica y ectópica

El hiperparatiroidismo primario (HPTP) es una afección producida por el exceso de secreción de hormona paratiroidea a partir de glándulas paratiroides que funcionan autárquicamente. Constituye la causa más común de hipercalcemia en la población. Por su embriología, las paratiroides son glándulas que pueden tener localizaciones ectópicas de forma frecuente. El HPTP se presenta en forma esporádica en el 90% de los casos, resultante en general de un adenoma único con expansiones monoclonales de una estirpe celular única. Menos frecuentemente (2-15%), se asocia con un segundo adenoma funcionante. La forma familiar (10%) se asocia a síndrome de neoplasias endócrinas múltiples (NEM) como NEM 1 y NEM 2A. Se presenta un caso de adenoma paratiroideo doble, con el segundo adenoma paratiroideo localizado en el mediastino, describiéndose los estudios preoperatorios y de localización glandular, así como los hallazgos operatorios.

Pediatric hyperparathyroidism: review and imaging update

Hyperparathyroidism, due to increased secretion of parathyroid hormones, may be primary, secondary or tertiary. Most pediatric patients with sporadic primary hyperparathyroidism will be symptomatic, presenting with either end-organ damage or nonspecific symptoms. In younger patients with primary hyperparathyroidism, there is a higher prevalence of familial hyperparathyroidism including germline inactivating mutations of the calcium-sensing receptor genes that result in either neonatal severe hyperparathyroidism or familial hypocalciuric hypercalcemia. Parathyroid scintigraphy and ultrasound are complementary, first-line imaging modalities for localizing hyperfunctioning parathyroid glands. Second-line imaging modalities are multiphase computed tomography (CT) and magnetic resonance imaging. In pediatrics, multiphase CT protocols should be adjusted to optimize radiation dose. Although, the role of these imaging modalities is better established in preoperative localization of hyperfunctioning parathyroid glands in primary hyperparathyroidism, the same principles apply in secondary and tertiary hyperparathyroidism. In this manuscript, we will review the embryology, anatomy, pathophysiology and preoperative localization of parathyroid glands as well as several subtypes of primary familial hyperparathyroidism. While most of the recent imaging literature centers on adults, we will focus on the issues that are pertinent and applicable to pediatrics.

Decreasing Surgical Management of Secondary Hyperparathyroidism in the United States

BACKGROUND

Secondary hyperparathyroidism (SHPT) commonly occurs in end-stage renal disease (ESRD), leading to vascular calcification and increased mortality. For SHPT refractory to medical management, parathyroidectomy improves symptoms and decreases mortality. Medical management has changed with the release of new guidelines and advent of novel medications. We investigate recent national trends in parathyroidectomy for SHPT.

MATERIALS AND METHODS

We used the National/Nationwide Inpatient Sample from 2004 to 2016 to identify hospitalizations including parathyroidectomy for SHPT and calculated parathyroidectomy rates utilizing data from the United States Renal Data System. Subgroup analysis was conducted by race. Risk factors for in-hospital mortality were identified with purposeful selection and multivariable logistic regression.

RESULTS

From 2004 to 2016, the rate of parathyroidectomies for SHPT per 1000 ESRD patients decreased from 6.07 (95% CI: 4.83-7.32) to 3.67 (95% CI: 3.33-4.00). Black patients underwent parathyroidectomy for SHPT at a 1.8-fold higher rate than white and Hispanic patients (5.59 versus 3.04 and 3.07). Almost all tracked comorbidities increased in prevalence. In-hospital mortality trended lower (1.5% to 0.8%, P = 0.051). Risk factors for in-hospital mortality included weight loss (OR 4.19, 95% CI: 2.00-8.78) and cardiac arrhythmia (OR 3.38, 95% CI: 1.66-6.91), while additional calendar year (OR = 0.87, 95% CI: 0.80-0.95) was protective.

CONCLUSIONS

The etiology of the declining parathyroidectomy rate for SHPT is unclear; possible factors include changing guidelines emphasizing medical management, widespread availability of cinacalcet, changing practice patterns, and inadequate surgical referral.

Re-operative Parathyroidectomy in Patients With Mild Primary Hyperparathyroidism

BACKGROUND

Surgery is the definitive management of primary hyperparathyroidism and the only curative therapy. However, many surgeons are hesitant to operate on individuals with mild primary hyperparathyroidism, with an even greater reluctance to operate on those who underwent a previous parathyroidectomy. We hypothesize that patients with mild primary hyperparathyroidism who undergo a re-operation have equivalent outcomes compared with those who undergo a first-time (FT) operation.

METHODS

We reviewed a prospective database of 459 patients with mild primary hyperparathyroidism who underwent surgery by one endocrine surgeon. Of these patients, 59 had a re-operative (RE-OP) parathyroid surgery. We compared these patients to those with mild primary hyperparathyroidism who had FT surgery (n = 400) using either the Pearson chi-square, Fisher's exact test, or Student's t-test where appropriate.

RESULTS

The mean age of our cohort was 60 ± 14 y, with 86% females. Patients in the RE-OP group had similar preoperative calcium and parathyroid hormone levels compared with those in the FT group. Most patients who underwent a RE-OP surgery had four gland hyperplasia on pathology (49.2%). Patients in the RE-OP and FT groups both had high and similar cure rates (100% versus 99.8%, P = 0.70). RE-OP patients had a higher rate of recurrent hyperparathyroidism (10.3% versus 3.3%, P = 0.025).

CONCLUSIONS

In patients with mild primary hyperparathyroidism, those who undergo RE-OP parathyroidectomy have a high cure rate that is similar to FT surgery. Therefore, we recommend that these patients with recurrence of mild hyperparathyroid disease be considered for parathyroidectomy.

A Nomogram to Predict Hungry Bone Syndrome After Parathyroidectomy in Patients With Secondary Hyperparathyroidism

BACKGROUND

Parathyroidectomy (PTX) has been demonstrated as an effective treatment for patients with secondary hyperparathyroidism (SHPT) of renal origin. However, severe hypocalcemia, called hungry bone syndrome (HBS), is a common complication following PTX in these patients and can lead to poor clinical outcomes, even death. Therefore, exploring risk factors for HBS and establishing a prediction nomogram allow intensive monitoring and prompt treating this postoperative complication, which is the main purpose of this study.

METHODS

From October 2016 to October 2018, PTX with autotransplantation (PTX + AT) procedures were performed in 131 patients with SHPT of renal origin by a surgeon and his team in the Thyroid and Parathyroid Surgery Center, West China Hospital, Sichuan University, China. After applying the inclusion and exclusion criteria, a total of 114 patients were enrolled for analyses in this study. Comprehensive data including preoperative, intraoperative, and postoperative variables were prospectively collected and retrospectively analyzed. The univariate and multivariate logistic regression analyses with internal validation by bootstrapping were used to confirm independent risk factors for postoperative HBS. The nomogram was developed based on the statistical analysis results. Receiver operator characteristic (ROC) curves were drawn to compare the prediction performance among different predictors.

RESULTS

The occurrence of postoperative HBS was 76.3% (87 out of 114 patients) in this study. Univariate analysis showed that preoperative intact parathyroid hormone (iPTH), serum alkaline phosphatase, bone-specific alkaline phosphatase (bone-ALP) were significantly higher in HBS group than those in non-HBS group, while preoperative corrected serum calcium and albumin were significantly lower in HBS group than those in non-HBS group. Total weight of resected parathyroid glands was significantly heavier in HBS group versus non-HBS group. Multivariate logistic regression analysis with internal validation by bootstrapping demonstrated preoperative iPTH, bone-ALP, preoperative corrected serum calcium, and total weight of resected parathyroid glands were independently associated with postoperative HBS. The nomogram including the abovementioned four independent predictors was constructed and showed better prediction performance than the other four predictors in terms of postoperative HBS.

CONCLUSIONS

On the basis of this study, we found higher preoperative iPTH level, higher bone-ALP level, heavier total weight of resected parathyroid glands, and lower preoperative corrected serum calcium level were independent predictors of postoperative HBS in patients with SHPT of renal origin. The nomogram can expediently, accurately, and objectively predict the risk of postoperative HBS in individual patient with SHPT of renal origin.

Influence of Parathyroidectomy on Kidney Graft Function in Secondary and Tertiary Hyperparathyroidism

BACKGROUND

Timing of parathyroidectomy (PTX) remains controversial in candidates for kidney transplant with concomitant renal hyperparathyroidism (HPT). The aim of this retrospective study was to identify the influence of early vs late posttransplant PTX compared to pretransplant PTX on renal graft function and morbidity.

METHODS

This single-center cohort study includes 57 patients with renal HPT and kidney transplantation treated between 2007 and 2017. Ninety-six patients had surgery for renal HPT between 2007 and 2017 as a consecutive sample. Group 1 (n = 30; tertiary HPT), group 2 (n = 66; secondary HPT). Of group 1, 4 patients were excluded for PTX before and after kidney transplantation. In group 2, 20 patients were excluded since they had not undergone kidney transplantation during follow-up. Twelve patients were excluded because of short follow-up (kidney transplantation in 2018), and 3 patients were excluded because of transplant failure within 90 days. Twenty-six patients underwent posttransplant PTX (10 patients within 12 months after transplant), and 31 patients had undergone PTX prior to kidney transplantation. Graft function, serum calcium concentrations, parathyroid hormone (PTH) levels, postoperative morbidity, and 90-day mortality were recorded.

RESULTS

Median age was 53.1 years in group 1 and 49.1 years in group 2. Most patients were male (53.8% in group 1; 54.8% in group 2). Median preoperative PTH levels were significantly different with 331.6 pg/mL in group 1 and 667.5 pg/mL in group 2 (P = .003). Creatinine levels changed little from 1.4 mg/dL (range, 0.8-2.5) to 1.7 mg/dL (range, 0.7-7.3) in group 1, and no difference was seen between early or late PTX after transplantation. In group 2, creatinine levels were 8.5 mg/dL (range, 4.6-11.7) before PTX and 8.7 mg/dL (range, 5.1-11.9) after PTX. We saw no correlation between postoperative PTH and kidney function. Thirty-five patients with postoperative PTH < 15 pg/mL displayed a mean postoperative creatinine of 5.5 mg/dL (range, 4.3-6.8), similar to other patients. Both the 30-day and 90-day mortality rates were zero.

CONCLUSIONS

PTX had no negative effect on graft function, whether performed before or after (early or late) kidney transplantation. Surgical cure of renal HPT should be performed as soon as possible to prevent secondary complications and can also be safely carried out early after transplantation.

The role of 18F-FCH PET/CT in patients with uremic hyperparathyroidism compared with 99mTc-sestaMIBI SPECT/CT and ultrasonography

BACKGROUND

The aim of this study was to evaluate the diagnostic efficacy of ¹⁸F-fluorocholine (¹⁸F-FCH) PET/CT for uremic hyperparathyroidism (uHPT) compared to ^99mTc-sestaMIBI SPECT/CT and ultrasonography (US).

METHODS

A total of 17 uHPT patients with stage 5 chronic kidney disease (CKD) were prospectively enrolled. All patients underwent US, ^99mTc-sestaMIBI SPECT/CT, and ¹⁸F-FCH within 2 months and received surgical treatment. Visual and quantitative methods were used for image analyses. Intraoperative localization and postoperative histological results of the reference standard as well as the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the three modalities were analyzed using Pearson's χ² tests. In addition, the diagnostic efficacy of ¹⁸F-FCH PET/CT for uHPT was evaluated. The relationships between PET parameters and laboratory parameters were assessed using the Spearman correlation coefficient.

RESULTS

A total of 63 parathyroid hyperplasia lesions were resected in 17 uHPT patients, and 53 lesions were detected using ¹⁸F-FCH PET/CT with no false-positive results. The sensitivity, specificity, accuracy, PPV, and NPV were 84.13%, 100%, 86.49%, 100%, and 52.38%, respectively. In comparison, the corresponding values for ^99mTc-sestaMIBI SPECT/CT and US were 63.49%, 90.91%, 67.57%, 97.56%, and 30.30% and 61.90%, 81.82%, 64.86%, 95.12%, and 27.27%, respectively. The volume of hyper-functioning parathyroid glands was significantly different between lesions positive in ¹⁸F-FCH PET/CT and negative in ¹⁸F-FCH PET/CT (mean volume 1.36 ± 0.55 cm³ vs. 0.83 ± 0.26 cm³; P = 0.019). US misidentified intrathyroidal parathyroid hyperplasia as thyroid nodules in three patients, while ¹⁸F-FCH PET correctly identified the anatomy. No significant associations were observed between PET parameters and laboratory parameters in uHPT.

CONCLUSION

¹⁸F-FCH PET/CT was more sensitive and accurate for uHPT than ^99mTc-sestaMIBI SPECT/CT and US, and had better preoperative diagnostic efficacy, particularly for lesions diagnosed as a thyroid nodule by US.