Long-term outcome after total parathyroidectomy for the management of secondary hyperparathyroidism

The refractory secondary hyperparathyroidism presenting with retro-orbital brown tumor: a case report

BACKGROUND

Tertiary hyperparathyroidism describes the autonomous and excessive secretion of parathyroid hormone (PTH) by the parathyroid glands after longstanding secondary hyperparathyroidism in chronic kidney disease. Brown tumors are a sign of uncontrolled hyperparathyroidism. In this case, we have reported a refractory and destructive hyperparathyroidism storm. Also, it presented with atypical onset and unexpected adenoma location.

CASE PRESENTATION

A 37-year-old man was diagnosed with end-stage kidney disease 22 years ago. He has been undergoing dialysis treatment since that time. Recently, he was admitted to the ophthalmology department due to the unilateral anterior bulging of the right eye and drooping of the eyelid. Magnetic resonance imaging exhibited an extraconal mass lesion located in the right orbital posterior superolateral position. Computerized tomography scans considered expansile bone lesion with peripheral calcification and originating from the sphenoid wing. The bone mass lesion was resected via craniotomy due to the compressive effect. The pathological findings were consistent with brown tumors. Plasma intact PTH level was 4557 pg/mL. The patient informed that he underwent parathyroidectomy and two leg fractures operation in a medical query. Parathyroid scintigraphy determined three distinct foci consistent with adenomas and one of them was in mediastenum. Second parathyroidectomy was recommended to the patient but the patient refused surgery. Despite his medication and dialysis regimen being revised, PTH levels were maintained at higher levels in follow-up.

CONCLUSIONS

We presented a hyperparathyroidism case that was resistant to all treatments and exhibited all the severe complications in a long-term dialysis patient. Furthermore, this case has revealed the importance and difficulty of secondary hyperparathyroidism management.

Total Parathyroidectomy Without Autotransplantation for ESRD Patients With Secondary Hyperparathyroidism; an Effective Alternative

BACKGROUND

The most common operations performed for secondary hyperparathyroidism include subtotal parathyroidectomy (STPX) and total parathyroidectomy with autotransplantation (TPX + AT). We present a series of ESRD patients treated with total parathyroidectomy without autotransplantation (TPX).

METHODS

This is a retrospective cohort analysis of ESRD patients, age 18 years or older, with three or more glands resected on final pathology and follow-up parathyroid hormone levels obtained up to 1.5 years postoperatively. The primary endpoint was recurrence of hyperparathyroidism (defined as PTH > 500 pg/mL).

RESULTS

The incidence of recurrent hyperparathyroidism at 1.5 years was 5.9% (2/34). The incidence of persistent hyperparathyroidism at 1.5 years was 11.8% (4/34). In this series, no patients were hospitalized for symptomatic hypocalcemia or experienced pathologic bone fractures.

CONCLUSIONS

Recurrence rates are low with TPX. The most common cause of recurrent and persistent disease is resection of three rather than four glands. The known complications of TPX, pathologic fractures, and severe hypocalcemia, were not seen in this study.

Predictive value of characteristics of resected parathyroid glands for persistent secondary hyperparathyroidism during parathyroidectomy

BACKGROUND

Parathyroidectomy (PTX), an effective treatment for refractory secondary hyperparathyroidism (SHPT) in chronic kidney disease (CKD) patients, still has a high persistent rate. This study aimed to analyze the predictive value of characteristics of resected parathyroid glands for postoperative persistent SHPT.

METHODS

The clinical data of patients with persistent SHPT and successful PTX controls who had or underwent total parathyroidectomy with forearm autotransplantation (TPTX + AT) was retrospectively collected. The characteristics including the number, minimum weight, maximum weight and total weight of resected parathyroid glands from each patient were recorded. Characteristics and cutoff value of resected parathyroid glands for the prediction of persistent SHPT were analyzed.

RESULTS

A total of 227 patients (62 persistent SHPT patients and 165 successful PTX controls) were enrolled in the study. Forty-one (66%) persistent SHPT cases related to supernumerary parathyroid and the remaining 21 (34%) cases related to residual undetected parathyroid. In addition, ectopic parathyroid was found in 8 patients (13%) before PTX. The average number of resected glands in the persistent SHPT group and successful PTX group was 3.53 ± 0.72 and 3.93 ± 0.25 respectively (p < 0.001). There was significance in the number of patients with different resected parathyroid glands between two groups (p < 0.001). When the resected gland number was 4, minimum weight of the parathyroid was noted to be heavier in the persistent SHPT group than that in the successful PTX group (0.52 ± 0.31 g vs. 0.38 ± 0.19 g, p < 0.001). For persistent SHPT prediction, cutoff value of minimum weight was 0.535 g, with sensitivity of 46% and specificity of 82% (AUC = 0.611; p = 0.029).

CONCLUSIONS

Major reason for the persistent SHPT is the existence of supernumerary parathyroid glands or resection of less than 4 glands. When 4 glands were resected, a minimum total parathyroid gland weight heavier than 0.535 g implied the potential presence of a missed supernumerary parathyroid gland, which also contributed to the persistent SHPT.

Recurrent renal secondary hyperparathyroidism caused by supernumerary mediastinal parathyroid gland and parathyromatosis: A case report

Background

Surgical parathyroidectomy (PTX) is necessary for patients with severe and progressive secondary hyperparathyroidism (SHPT) refractory to medical treatment. Recurrence of SHPT after PTX is a serious clinical problem. Both supernumerary mediastinal parathyroid gland and parathyromatosis are the rare causes of recurrent renal SHPT. We report a rare case of recurrent renal SHPT due to supernumerary mediastinal parathyroid gland and parathyromatosis.

Case presentation

A 53-year-old man underwent total parathyroidectomy with autotransplantation due to the drug-refractory SHPT 17 years ago. In the last 11 months, the patient experienced symptoms including bone pain and skin itch, and the serum intact parathyroid hormone (iPTH) level elevated to 1,587 pg/ml. Ultrasound detected two hypoechoic lesions located at the dorsal area of right lobe of the thyroid gland, and both lesions presented as characteristics of hyperparathyroidism in contrast-enhanced ultrasound. ^99mTc-MIBI/SPECT detected a nodule in the mediastinum. A reoperation involved a cervicotomy for excising parathyromatosis lesions and the surrounding tissue and a thoracoscopic surgery for resecting a mediastinal parathyroid gland. According to a histological examination, two lesions behind the right thyroid lobe and one lesion in the central region had been defined as parathyromatosis. A nodule in the mediastinum was consistent with hyperplastic parathyroid. The patient remained well for 10 months with alleviated symptoms and stabilized iPTH levels in the range of 123-201 pg/ml.

Conclusion

Although rare, recurrent SHPT may be caused by a coexistence of both supernumerary parathyroid glands and parathyromatosis, which should receive more attention. The combination of imaging modalities is important for reoperative locations of parathyroid lesions. To successfully treat parathyromatosis, all the lesions and the surrounding tissue must be excised. Thoracoscopic surgery is a reliable and safe approach for the resection of ectopic mediastinal parathyroid glands.

Use of fluorescence imaging and indocyanine green during thyroid and parathyroid surgery: Results of an intercontinental, multidisciplinary Delphi survey

BACKGROUND

In recent years, fluorescence imaging-relying both on parathyroid gland autofluorescence under near-infrared light and angiography using the fluorescent dye indocyanine green-has been used to reduce risk of iatrogenic parathyroid injury during thyroid and parathyroid resections, but no published guidelines exist regarding its use. In this study, orchestrated by the International Society for Fluorescence Guided Surgery, areas of consensus and nonconsensus were examined among international experts to facilitate future drafting of such guidelines.

METHODS

A 2-round, online Delphi survey was conducted of 10 international experts in fluorescence imaging use during endocrine surgery, asking them to vote on 75 statements divided into 5 modules: 1 = patient preparation and contraindications to fluorescence imaging (n = 11 statements); 2 = technical logistics (n = 16); 3 = indications (n = 21); 4 = potential advantages and disadvantages of fluorescence imaging (n = 20); and 5 = training and research (n = 7). Several methodological steps were taken to minimize voter bias.

RESULTS

Overall, parathyroid autofluorescence was considered better than indocyanine green angiography for localizing parathyroid glands, whereas indocyanine green angiography was deemed superior assessing parathyroid perfusion. Additional surgical scenarios where indocyanine green angiography was thought to facilitate surgery are (1) when >1 parathyroid gland requires resection; (2) during redo surgeries, (3) facilitating parathyroid autoimplantation; and (4) for the predissection visualization of abnormal glands. Both parathyroid autofluorescence and indocyanine green angiography can be used during the same procedure and employing the same imaging equipment. However, further research is needed to optimize the dose and timing of indocyanine green administration.

CONCLUSION

Though further research remains necessary, using fluorescence imaging appears to have uses during thyroid and parathyroid surgery.

Effect of total parathyroidectomy in patients with secondary hyperparathyroidism: a retrospective study

Purpose

To investigate the therapeutic efficacy, feasibility, and safety of total parathyroidectomy (tPTX) in the treatment of secondary hyperparathyroidism (SHPT).

Methods

The clinical data of 34 SHPT patients admitted to the Department of Nephrology, Yuxi People’s Hospital, from January 2018 to January 2021 who had received tPTX, were retrospectively analyzed. The indications for tPTX were severe SHPT that did not respond to medical treatment and was ineligible for kidney transplantation. tPTX without autotransplantation was adopted to compare the level of symptom relief and changes in serum intact parathyroid hormone (iPTH), blood calcium, and blood phosphorus pre- and postoperatively.

Results

In 34 patients, 142 parathyroid glands were removed, including 21 ectopic parathyroid glands (14.78%). Six patients (17.64%, 6/34) had supernumerary parathyroid glands. At 6 h postoperatively, arthralgia and bone pain were significantly reduced to almost zero in 94.12% (32/34) of patients. At 24 h postoperatively, relief of bone pain and improvement of limb movement were observed in 100% (34/34) of patients, and pruritus almost disappeared in 86.36% (19/22) of patients. There were significant differences in iPTH (χ2 = 134.93, P < 0.05), calcium (χ2 = 23.02, P < 0.05), and phosphorus (χ2 = 102.11, P < 0.05) levels preoperatively and 40 min, 24 h, 1 week, half a year, and last available (> 1 year) postoperatively.

The patients were followed up for 15–47 months (median 33 months). Hypoparathyroidism was observed in three patients, who underwent neck dissection or partial thymotomy concurrently for different reasons. No intractable hypocalcemia or adynamic bone disease occurred during the follow-up period.

Conclusion

In SHPT patients who were ineligible for renal transplantation, tPTX was effective, safe, and reliable, with a low recurrence rate. However, when tPTX was performed alone without autologous transplantation, bilateral neck exploration was sufficient, and central neck dissection and thymic resection were inadvisable.

Single-Center Experience of Parathyroidectomy Using Intraoperative Parathyroid Hormone Monitoring

Background and Objectives: Hyperparathyroidism (HPT) is a rare endocrine disease associated with the elevated metabolism of calcium, vitamin D, and phosphate by the hyperfunctioning of the parathyroid glands. Here, we report our experience of parathyroidectomy using intraoperative parathyroid hormone (IOPTH) monitoring in a single tertiary hospital. Materials and Methods: From October 2018 to January 2022, a total of 47 patients underwent parathyroidectomy for HPT. We classified the patients into two groups—primary HPT (PHPT, n = 37) and renal HPT (RHPT, n = 10)—and then reviewed the patients’ data, including their general characteristics, laboratory results, and perioperative complications. Results: Thirty-five of the thirty-seven patients in the PHPT group underwent focused parathyroidectomy, while all ten patients in the RHPT group underwent subtotal parathyroidectomy. IOPTH monitoring based on the Milan criteria was used in all cases. Preoperative and 2-week, 6-month, and 12-month postoperative parathyroid hormone (PTH) levels were within the normal range in the PHPT group, whereas they were higher than normal in the RHPT group. Transient hypocalcemia occurred only in the RHPT group, with calcium levels returning to normal levels 12 months after surgery. Conclusions: Parathyroidectomy with IOPTH monitoring in our hospital showed favorable clinical outcomes. However, owing to the small number of patients due to the low frequency of parathyroid disease, long-term, prospective studies are needed in the future.

Efficacy and safety of radiofrequency ablation for primary and secondary hyperparathyroidism with or without previous parathyroidectomy: a retrospective study

INTRODUCTION

This study aimed to investigate and compare the therapeutic efficacy and safety of ultrasound-guided radiofrequency ablation (RFA), between primary hyperparathyroidism (PHPT) and secondary hyperparathyroidism (SHPT) patients, with or without previous parathyroidectomy (PTX).

SUBJECTS AND METHODS

A total of 21 patients (7 PHPT, 14 SHPT) underwent RFA for hyperparathyroidism (HPT) at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Five of the 14 SHPT patients had previously received PTX. The laboratory data, volume change of each parathyroid nodule, symptomatic scores, and complications were analyzed and compared between all groups at 1 and 7 days, and at 1, 3, 6, and 12 months after RFA.

RESULTS

After RFA, the volume reduction ratio (VRR) for all patients at the last follow-up was 93.76%, and clinical symptoms significantly improved. At 12 months, all PHPT patients achieved successful treatment of intact PTH (iPTH). In SHPT patients, the mean iPTH value significantly decreased 1-day post-RFA, subsequently exhibiting a transient rebound which proceeded to decrease, with 57.1% reaching successful treatment standards. SHPT patients with PTX showed a lower complication score, shorter ablation time, higher iPTH baseline and outcomes, and lower VRR, compared to patients without PTX. The serum calcium level significantly decreased to normal range in 85.7% of all patients at 12 months. Severe hypocalcemia occurred in 23.8% at 1 week, and all were corrected with calcium supplements.

CONCLUSIONS

RFA demonstrates a therapeutic efficacy similar to PTX. It can thus be considered an effective alternative treatment for PHPT, SHPT, or post-PTX patients who are unsuitable for another PTX.

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.

Hyperkalemia Following Parathyroidectomy in Patients with Renal Hyperparathyroidism-New Thresholds for Urgent Perioperative Dialysis

Parathyroidectomy (PTX) is a mainstay of treating secondary hyperparathyroidism (SHPT) in patients with kidney failure in order to reduce the incidence of cardiovascular events (CVE), increase overall survival and improve quality of life. Perioperative hyperkalemia may lead to devastating cardiac complications. Distinct preoperative thresholds for serum potassium levels (SPL) were defined, but neither their usefulness nor consecutive risks are understood. This study compared the results and efficacy of different clinical procedures in preventing or treating perioperative hyperkalemia, including postoperative urgent hemodialysis (UHD). Methods: Patients from Charité-Universitätsmedizin Berlin and Rheinland Klinikum Lukaskrankenhaus, Neuss, undergoing PTX due to SHPT between 2008 and 2018 were analyzed retrospectively with regard to demographic parameters, surgery specific conditions and perioperative laboratory results. Comparisons of patient values from both centers with focus on perioperative hyperkalemia and the need for UHD were performed. Results: A total of 251 patients undergoing PTX for SHPT were included (Neuss: n = 121 (48%); Berlin: n = 130 (52%)). Perioperative hyperkalemia (SPL ≥ 5.5 mmol/L) was noted in 134 patients (53%). UHD on the day of surgery was performed especially in patients with intraoperative hyperkalemia, in females (n = 40 (16%) vs. n = 27 (11%); p = 0.023), in obese patients (n = 27 (40%) vs. n = 50 (28%), p = 0.040) and more often in patients treated in Neuss (n = 42 (35%) vs. 25 (19%); p = 0.006). For patients treated in Neuss, the intraoperative hyperkalemia cut-off level above 5.75 mmol/L was the most predictive factor for UHD (n = 30 (71%) vs. n = 8 (10%); p < 0.001). Concerning secondary effects of hyperkalemia or UHD, no patient died within the postoperative period, and only three patients suffered from acute CVE, with SPL > 5.5 mmol/L measured in only one patient. Conclusion: Perioperative values could not predict postoperative hyperkalemia with the need for UHD. Previously defined cut-off levels for SPL should be reconsidered, especially for patients undergoing PTX. Early postoperative dialysis in patients with postoperative hyperkalemia can be performed with a low risk for complications and may be indicated for all patients with increased perioperative SPL.

[Risk factors affecting graft survival after parathyroidectomy and parathyroid autotransplantation in patients on maintenance hemodialysis]

OBJECTIVE

To investigate the risk factors affecting the survival of parathyroid autograft following total parathyroidectomy combined with autologous sternocleidomastoid muscle transplantation (TPTX + AT) in patients on maintenance hemodialysis (MHD) complicated with secondary hyperparathyroidism (SHPT).

OBJECTIVE

This retrospective study was conducted among the patients on maintenance hemodialysis with SHPT, who underwent successful parathyroidectomy and autotransplantation from January, 2010 to February, 2020 in our hospital. The clinical data and serum levels of calcium, phosphorus, intact parathyroid hormone, hemoglobin, and alkaline phosphatase (ALP) of the patients were collected. The enrolled patients were divided into survival group with bilateral forearm parathyroid hormone (iPTH) ratio > 1.5 and death group with a ratio < 1.5 at 2 weeks after surgery for comparison of the clinical data and perioperative indicators. The risk factors of postoperative parathyroid autograft survival were analyzed using logistic regression analysis.

OBJECTIVE

A total of 87 patients were included in the study, among whom the graft survival rate after parathyroid transplantation was 78.16%. In both groups, serum levels of calcium, phosphorus, iPTH and ALP decreased and hemoglobin level increased significantly at 1 week and 1, 2, 3, 6 and 12 months after surgery (P < 0.01). Logistic regression analysis showed that serum ALP level was an independent risk factor for graft survival following parathyroid autotransplantation [OR=1.003, 95% CI: 1.001-1.005, P=0.004].

OBJECTIVE

TPTX+AT is a safe and effective treatment for SHPT, and parathyroid autografts are less likely to survive following parathyroid transplantation in patients with high preoperative level of ALP.

Diagnostic Values of Intraoperative (1-84) Parathyroid Hormone Levels are Superior to Intact Parathyroid Hormone for Successful Parathyroidectomy in Patients With Chronic Kidney Disease

OBJECTIVE

Persistent secondary hyperparathyroidism (SHPT) may occur because of residual cervicothoracic parathyroids in parathyroidectomy (PTX) patients with chronic kidney disease. We prospectively compared the predictive values of intraoperative plasma (1-84) parathyroid hormone (PTH) and intact PTH (iPTH) levels to improve the safety and efficacy of PTX.

METHODS

We included 100 healthy controls, 162 stage 5 chronic kidney disease patients without SHPT, and 214 patients who underwent PTX because of SHPT. Plasma iPTH and (1-84) PTH levels were measured before incision (io-iPTH0 and io-[1-84]PTH0, respectively) and 10 minutes (io-iPTH10 and io-[1-84]PTH10, respectively) and 20 minutes (io-iPTH20 and io-[1-84]PTH20, respectively) after removing all parathyroids. The percentage reduction of iPTH and (1-84) PTH at 10 minutes (io-iPTH10% and io-[1-84]PTH10%, respectively) and 20 minutes (io-iPTH20%, and io-[1-84]PTH20%, respectively) was calculated. iPTH and (1-84) PTH were measured using second- and third-generation PTH assays, respectively.

RESULTS

Compared with the controls and non-PTX patients, the PTX group had more obvious mineral metabolism disorders. There were 187 successful PTXs, 19 patients with persistent SHPT, and 8 patients lost to follow-up. The receiver operating characteristic curves revealed that io-(1-84)PTH10% >86.6% and io-(1-84)PTH20% >87.5% suggested successful PTX. The sensitivity of io-iPTH20% and io-(1-84)PTH20% were higher than those at the timepoint of 10 minutes. Moreover, the specificity and sensitivity of the (1-84) PTH reduction percentage were superior to that of iPTH.

CONCLUSION

Intraoperative reduction percentages of plasma (1-84) PTH levels are superior to iPTH for accurately predicting successful PTX, especially at 20 minutes after all cervicothoracic parathyroids had been resected.

Surgical Management of Secondary Hyperparathyroidism

Secondary hyperparathyroidism (SHPT) affects a majority of patients with chronic kidney disease (CKD) of stage 3 or worse. Despite the development of calcimimetics and their effectiveness in treating SHPT, many patients continue to fail medical management and should be referred to a parathyroid surgeon. In this narrative review, we summarize the indications for surgical referral, preoperative planning, intraoperative strategies to guide resection, and postoperative management. In the absence of universal guidelines, it can be difficult to determine when it is appropriate to make this referral. The majority of studies evaluating parathyroidectomy (PTX) for SHPT use the criteria of parathyroid hormone level (PTH) >800 pg/ml with hypercalcemia and/or hyperphosphatemia, which may be accompanied by symptoms such as bone pain and pruritis that can improve after surgery. Although the reported utility of the various imaging modalities (i.e., 99m-technetium-sestamibi scintigraphy with computed tomography [SPECT/CT], CT, or ultrasound) is highly variable in SHPT, SPECT/CT appears to be the most sensitive. Intraoperatively, PTH monitoring is effective in predicting long-term cure of SHPT but not in predicting hypoparathyroidism. Ectopic and supernumerary parathyroid glands are common in these patients and are often implicated in persistent or recurrent disease. Postoperatively, patients are at risk of severe hypocalcemia and hungry bone syndrome requiring close monitoring and replenishment.

Surgical Outcomes of Subtotal Parathyroidectomy for Renal Hyperparathyroidism

OBJECTIVES

The aim of this study was to evaluate the effectiveness of subtotal parathyroidectomy for patients with renal hyperparathyroidism.

METHODS

We studied 25 patients with renal hyperparathyroidism who underwent subtotal parathyroidectomy from October 2002 to October 2017. We analyzed serum intact parathyroid hormone (iPTH), calcium, and inorganic phosphorus levels before and at multiple time points following surgery, and evaluated the surgical outcomes and complications.

RESULTS

Of the 25 patients, 13 (52%) were male and 12 (48%) were female, and the mean age was 53.4±9.3 years. The mean duration of dialysis before parathyroidectomy was 156.8±79.5 months. Mean preoperative serum iPTH and calcium levels were 1,199.0±571.3 pg/mL and 10.5±1.0 mg/dL, respectively. At 6 months postoperatively, the mean iPTH and calcium levels decreased to 49.2±47.6 pg/mL (P<0.01) and 8.0±1.0 mg/dL (P<0.01), respectively. Recurrent hyperparathyroidism occurred in two patients: one subsequently underwent kidney transplantation and the other continued hemodialysis and maintained normal calcium levels. One patient developed postoperative permanent hypoparathyroidism.

CONCLUSION

Subtotal parathyroidectomy is a safe and effective surgical treatment for renal hyperparathyroidism.

99mTc-MIBI SPECT/CT imaging had high sensitivity in accurate localization of parathyroids before parathyroidectomy for patients with secondary hyperparathyroidism

Purpose: Accurate preoperative parathyroid localization is important for successful parathyroidectomy (PTX). The aim of our study was to investigate whether SPECT/CT has enhanced effect in preoperative localization of parathyroids. Methods: In our retrospective cohort study, we evaluated the effects of technetium-99m methoxyisobutylisonitrile-single-photon emission computed tomography/computed tomography (^99mTc-MIBI SPECT/CT) on preoperative parathyroid localization for 645 secondary hyperparathyroidism (SHPT) patients. Among them, 569 successful PTX patients were divided into group A (received ^99mTc-MIBI scintigraphy, n = 175) and group B (received ^99mTc-MIBI scintigraphy and SPECT/CT imaging, n = 394). Sensitivity, specificity, and consistency of two imaging methods in preoperative localization of parathyroids were compared. Results: Overall sensitivity and consistency were higher in group B, while there was no difference in specificity between the two groups. In group A, the sensitivity of ^99mTc-MIBI was 50.00%, 77.11%, 61.76%, and 76.54% in the right upper gland (RU), right lower gland (RL), left upper gland (LU), and left lower gland (LL) subgroups, while the consistency was 52.00%, 76.57%, 61.71%, and 75.43%, respectively. In group B, the sensitivity of ^99mTc-MIBI with SPECT/CT was 69.39%, 90.03%, 78.07%, and 84.27%, and the consistency was 69.54%, 88.32%, 78.43%, and 84.26%, respectively. The sensitivity and consistency in lower glands were higher than in upper glands in both groups. Sensitivity for eutopic parathyroid was higher in group B, while there was no difference for ectopic parathyroid. Conclusions: ^99mTc-MIBI SPECT/CT can increase the sensitivity and consistency of preoperative localization of eutopic parathyroid glands, and it can accurately locate ectopic parathyroid without sensitivity improvement.

Trauma-induced primary hypoparathyroidism following severe bite wound injury to the neck in a dog

OBJECTIVE

To describe the clinical presentation and outcome of a dog with primary hypoparathyroidism secondary to cervical bite wounds.

CASE SUMMARY

A 3-year-old male intact Chihuahua presented after being attacked by a large breed dog. The dog sustained severe cervical lacerations, exposing the trachea and jugular veins. A portion of the right thyroid gland was missing. The dog was stabilized before wound debridement and closure. Ionized calcium concentrations were within reference range at the time of presentation. Forty-eight hours after the initial trauma, the dog was presented in lateral recumbency with signs of hypovolemic shock, muscle tremors, and hyperthermia. Bloodwork showed severe ionized hypocalcemia with low normal parathyroid hormone concentration consistent with acute primary hypoparathyroidism. The dog was managed initially with IV calcium gluconate and calcitriol, then long-term oral calcium carbonate and vitamin D3. After 6 months, the dog was successfully weaned off calcium supplementation.

NEW OR UNIQUE INFORMATION PROVIDED

This is the first described case of traumatic primary hypoparathyroidism after a bite injury to the neck in a dog.

Predictors of early postoperative hypocalcemia after total parathyroidectomy in renal hyperparathyroidism

Purpose

Patients with secondary hyperparathyroidism are at high risk for developing postoperative hypocalcemia. However, there are limited data regarding predictors of postoperative hypocalcemia in renal failure patient with secondary hyperparathyroidism. This study aimed to determine the clinical presentations of renal hyperparathyroidism and the predictors of early postoperative hypocalcemia after total parathyroidectomy.

Methods

Data of patients with renal hyperparathyroidism who underwent total parathyroidectomy between January 2007 to December 2014 were reviewed retrospectively. Patients were divided into 2 cohort groups according to their serum calcium levels within 24 hours of parathyroidectomy: the hypocalcemia group (calcium levels of 2 mmol/L or less), and the normocalcemia group (calcium levels more than 2 mmol/L). With the use of multivariable logistic regression analyses, the predictors of early postoperative hypocalcemia after total parathyroidectomy in patients with renal hyperparathyroidism were investigated.

Results

Among 68 patients, 56 patients (82.4%) were symptomatic preoperatively. Fifty patients (73.5%) presented with bone pain and 14 patients (20.6%) had muscle weakness. Early postoperative hypocalcemia occurred in 25 patients (36.8%). Preoperative alkaline phosphatase level was the predictor of early postoperative hypocalcemia (adjusted odds ratio, 1.004; 95% confidence interval, 1.001–1.006; P = 0.002).

Conclusion

Results from our study show that most of the patients with renal hyperparathyroidism were symptomatic preoperatively and the most common clinical presentations were bone pain and muscle weakness. The significant predictor of early postoperative hypocalcemia after total parathyroidectomy was the preoperative alkaline phosphatase levels.

Parathyroid Hormone Fragments: New Targets for the Diagnosis and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder

As a common disorder, chronic kidney disease (CKD) poses a great threat to human health. Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a complication of CKD characterized by disturbances in the levels of calcium, phosphorus, parathyroid hormone (PTH), and vitamin D; abnormal bone formation affecting the mineralization and linear growth of bone; and vascular and soft tissue calcification. PTH reflects the function of the parathyroid gland and also takes part in the metabolism of minerals. The accurate measurement of PTH plays a vital role in the clinical diagnosis, treatment, and prognosis of patients with secondary hyperparathyroidism (SHPT). Previous studies have shown that there are different fragments of PTH in the body's circulation, causing antagonistic effects on bone and the kidney. Here we review the metabolism of PTH fragments; the progress being made in PTH measurement assays; the effects of PTH fragments on bone, kidney, and the cardiovascular system in CKD; and the predictive value of PTH measurement in assessing the effectiveness of parathyroidectomy (PTX). We hope that this review will help to clarify the value of accurate PTH measurements in CKD-MBD and promote the further development of multidisciplinary diagnosis and treatment.

Interrelated role of Klotho and calcium-sensing receptor in parathyroid hormone synthesis and parathyroid hyperplasia

The pathogenesis of parathyroid gland hyperplasia is poorly understood, and a better understanding is essential if there is to be improvement over the current strategies for prevention and treatment of secondary hyperparathyroidism. Here we investigate the specific role of Klotho expressed in the parathyroid glands (PTGs) in mediating parathyroid hormone (PTH) and serum calcium homeostasis, as well as the potential interaction between calcium-sensing receptor (CaSR) and Klotho. We generated mouse strains with PTG-specific deletion of Klotho and CaSR and dual deletion of both genes. We show that ablating CaSR in the PTGs increases PTH synthesis, that Klotho has a pivotal role in suppressing PTH in the absence of CaSR, and that CaSR together with Klotho regulates PTH biosynthesis and PTG growth. We utilized the tdTomato gene in our mice to visualize and collect PTGs to reveal an inhibitory function of Klotho on PTG cell proliferation. Chronic hypocalcemia and ex vivo PTG culture demonstrated an independent role for Klotho in mediating PTH secretion. Moreover, we identify an interaction between PTG-expressed CaSR and Klotho. These findings reveal essential and interrelated functions for CaSR and Klotho during parathyroid hyperplasia.

Clinical predictor of postoperative hyperkalemia after parathyroidectomy in patients with hemodialysis

OBJECTIVE

Hyperkalaemia is one of the most common reasons for patients requiring emergency treatment. This study is to investigate the risk factors of postoperative hyperkalemia in renal failure patients undergoing parathyroidectomy with autotransplantation (PTXa).

METHODS

One hundred and eight patients [ 54 men and 54 women; age, 45.1 ± 11.1 years (mean ± SD)] with secondary hyperparathyroidism undergoing parathyroidectomy with autotransplantation were involved in this study. Laboratory chemistries (hemoglobin, fasting blood glucose, serum calcium level, alkaline phosphatase, phosphorus, parathyroid hormone) were measured before surgery. Serum potassium level was obtained before surgery and at 0 h after surgery.

RESULTS

Serum potassium level increased in 108 patients after surgery (P < 0.05). Sixteen patients (14.8%) potassium levels rose more than 6.0 mmol/L after parathyroidectomy with autotransplantation. Age and preoperative serum potassium level were significantly negative correlated with postoperative serum potassium level. Correlation analysis and receiver operating characteristic curve method confirmed that use of the preoperative serum potassium level was the primary predictor of postoperative hyperkalemia. The cutoff point for preoperative serum potassium level was 4.40 mmol/L, according to the Youden index of the receiver operating characteristic curve.

CONCLUSIONS

Preoperative serum potassium increased after parathyroidectomy with autotransplantation in patients with secondary hyperparathyroidism. The preoperative serum potassium level could help the surgeon to predict postoperative hyperkalemia in case of emergency dialysis following surgery.

Lesion based diagnostic performance of dual phase 99mTc-MIBI SPECT/CT imaging and ultrasonography in patients with secondary hyperparathyroidism

Background

We aimed to evaluate the diagnostic performance of ^99mTc-MIBI SPECT/CT and ultrasonography in patients with secondary hyperparathyroidism (SHPT), and explored the factors that affect the diagnostic performance.

Methods

^99mTc-MIBI SPECT/CT and ultrasonography were performed in 50 patients with SHPT within 1 month before they underwent surgery. Imaging results were confirmed by the pathology. Pearson correlation analysis was used to determine the correlation of PTH level with clinical data. The optimal cutoff value for predicting positive ^99mTc-MIBI results was evaluated by ROC analysis in lesions diameter.

Results

Forty-nine patients had a positive ^99mTc-MIBI imaging results and 39 patients had positive ultrasonography results. The sensitivities of ^99mTc-MIBI and ultrasonography were 98.00% and 78.00%, respectively. A total of 199 lesions were resected in 50 patients. Among them, 183 lesions were proved to be parathyroid hyperplasia. On per-lesion basis analysis, the sensitivity and specificity of ^99mTc-MIBI and ultrasonography were 59.34% and 75.00% vs 46.24% and 80.00%, respectively. The Pearson correlation analysis showed that the serum AKP and PTH level had a significant linear association (r = 0.699, P < 0.001). The lesion diameter was a statistically significant predictive factor in predicting positive ^99mTc-MIBI SPECT/CT. The optimal cutoff value for predicting positive ^99mTc-MIBI results evaluated by ROC analysis in lesions diameter was 8.05 mm.

Conclusion

Dual phase ^99mTc-MIBI SPECT/CT imaging had a higher sensitivity in patients with SHPT than ultrasonography. Therefore, using ^99mTc-MIBI positioning the lesion could be an effective method pre-surgical in patients with SHPT.

Intraoperative Parathyroid Localization with Near-Infrared Fluorescence Imaging Using Indocyanine Green during Total Parathyroidectomy for Secondary Hyperparathyroidism

The detection of all glands during total parathyroidectomy (TPTX) in secondary hyperparathyroidism (SHPT) patients is often difficult due to their variability in number and location. The objective of this study was to evaluate the feasibility of near-infrared fluorescence (NIRF) imaging using indocyanine green (ICG) for intraoperative parathyroid gland (PTG) localization in SHPT patients. Twenty-nine patients with SHPT were divided into two groups with or without intraoperative NIRF imaging. ICG was administered in patients undergoing intraoperative imaging, and the fluorescence of PTGs was assessed. Clinical and histopathologic variables were analyzed to determine factors associated with ICG uptake. Comparisons between NIRF and preoperative imaging, as well as differences between groups with or without NIRF imaging, were carried out to evaluate the efficacy of this technique. Most PTGs could be clearly identified, including one ectopic gland. The sensitivity of NIRF imaging is 91.1% in contrast to 81.82% for ultrasonography (US), 62.34% for ^99mTc-MIBI and 85.71% for computed tomography (CT). In addition, intraoperative NIRF imaging can reduce the operation time and improve the complete resection rate compared with the group not using it. Intraoperative NIRF imaging using ICG during TPTX is technically feasible and reliable for assisting surgeons in detecting and confirming PTGs.

To assess the effects of parathyroidectomy (TPTX versus TPTX+AT) for Secondary Hyperparathyroidism in chronic renal failure: A Systematic Review and Meta-Analysis

BACKGROUND

Secondary Hyperparathyroidism (SHPT) requiring parathyroidectomy (PTX) occurs more commonly in patients with progressive chronic kidney disease and in those on long-term lithium therapy. Successful PTX often results in a dramatic drop of parathyroid hormone level, relieves the patient from clinical symptoms, and reduces mortality. However, there is an ongoing debate on the optimal surgical treatment of SHPT. Currently, no clinical guidelines or trials have definitely answered the question of whether Total Parathyroidectomy (TPTX) is superior or equal to Total Parathyroidectomy with Autotransplantation (TPTX + AT).

OBJECTIVE

The aims of the study were to compare the efficacy of two different surgical procedures and to develop evidence-based practice guidelines for the treatment of SHPT.

METHODS

Citations were identified in the Medline, Cochrane, EMBASE, and Chinese Biomedical Literature databases through November 2016. The Newcastle-Ottawa Scale (NOS) score was used to assess the methodological quality of the studies included. All data were analyzed using Review Manager 5.3.

RESULTS

A total of nine cohort studies and one Randomized Controlled Trials (RCT), comprising 1283 patients, were identified. The NOS score of all the studies included was 5 or above. Compared with TPTX + AT, patients in the TPTX group had lower rates of "recurrence" (OR = 0.20; 95%CI, 0.11-0.38; P < 0.01), "recurrence or persistence" (OR = 0.18; 95%CI, 0.10-0.33; P < 0.01), "reoperation due to recurrence or persistence" (OR = 0.17; 95%CI, 0.06-0.54; P = 0.002), and shorter "operative time" (WMD = -17.30; 95%CI, -30.53 to -4.06; P < 0.05), except for a higher risk of "hypoparathyroidism" (OR = 2.97; 95%CI, 1.09-8.08; P = 0.01). However, none of the patients had developed permanent hypocalcemia or adynamic bone disease. No significant difference was found for "symptomatic improvement", "complications", "drug requirements", and "hospital stay" (P > 0.05).

CONCLUSION

The findings indicate that TPTX is superior to TPTX + AT, while referring to the rate of recurrent SHPT. However, this conclusion needs to be tested in large-scale confirmatory trials. TPTX seems to be a feasible alternative therapeutic option for the surgical treatment of refractory SHPT.

Diagnostic Accuracy Study of Intraoperative and Perioperative Serum Intact PTH Level for Successful Parathyroidectomy in 501 Secondary Hyperparathyroidism Patients

Parathyroidectomy (PTX) is an effective treatment for severe secondary hyperparathyroidism (SHPT); however, persistent SHPT may occur because of supernumerary and ectopic parathyroids. Here a diagnostic accuracy study of intraoperative and perioperative serum intact parathyroid hormone (iPTH) was performed to predict successful surgery in 501 patients, who received total PTX + autotransplantation without thymectomy. Serum iPTH values before incision (io-iPTH0), 10 and 20 min after removing the last parathyroid (io-iPTH10, io-iPTH20), and the first and fourth day after PTX (D1-iPTH, D4-iPTH) were recoded. Patients whose serum iPTH was >50 pg/mL at the first postoperative week were followed up within six months. Successful PTX was defined if iPTH was <300 pg/mL, on the contrary, persistent SHPT was regarded. There were 86.4% patients underwent successful PTX, 9.8% remained as persistent SHPT and 3.8% were undetermined. Intraoperative serum iPTH demonstrated no significant differences in two subgroups with or without chronic hepatitis. Receiver operating characteristic (ROC) curves showed that >88.9% of io-iPTH20% could predict successful PTX (area under the curve [AUC] 0.909, sensitivity 78.6%, specificity 88.5%), thereby avoiding unnecessary exploration to reduce operative complications. D4-iPTH >147.4 pg/mL could predict persistent SHPT (AUC 0.998, sensitivity 100%, specificity 99.5%), so that medical intervention or reoperation start timely.

Surgical management of secondary hyperparathyroidism: how to effectively reduce recurrence at the time of primary surgery

BACKGROUND

Successful parathyroidectomy (PTX) often results in a dramatic drop in the parathyroid hormone (PTH) levels, relieves the patient from clinical symptoms, and reduces mortality. Although PTX is generally a successful treatment for progressive secondary hyperparathyroidism (SHPT) patients subjected to surgery, a significant proportion develops recurrent SHPT following PTX.

KEY MESSAGE

SHPT requiring PTX occurs more commonly in progressive chronic kidney disease and in long-term lithium therapy. Operative approaches include subtotal PTX, total PTX with or without autotransplantation, and possible thymectomy. Each approach has its proponents, advantages, and disadvantages. Although PTX offers the highest percentage cure for SHPT, compared to all other medical and surgical treatment, recurrent hyperparathyroidism can be observed in some patients dependent on follow-up time. A literature review and analysis of recent data regarding how to reduce recurrence of SHPT at the time of primary surgery was performed. The current literature and our own experience in the field have confirmed that pre-operative imaging, thymectomy, stereo magnifier, and surgical procedure may effectively reduce recurrence of SHPT at the time of primary surgery.

Intra-operative parathyroid hormone monitoring through central laboratory is accurate in renal secondary hyperparathyroidism

OBJECTIVE

The usefulness, the methods and the criteria of intra-operative monitoring of the parathyroid hormone (ioPTH) during parathyroidectomy (PTX) for renal secondary hyperparathyroidism (rSHPT) in patients on chronic hemodialysis remain still matter of debate. The present study aimed to evaluate the ability of a low cost central-laboratory second generation PTH assay to predict an incomplete resection of parathyroid glands (PTG).

METHODS

The ioPTH decay was determined In 42 consecutive patients undergoing PTX (15 subtotal and 27 total without auto-transplant of PTG) for rSHPT. The ioPTH monitoring included five samples: pre-intubation, post-manipulation of PTG and at 10, 20 and 30min post-PTG excision. The patients with PTH exceeding the normal value (65pg/ml) at the first postoperative week, 6 and 12months were classified as persistent rSHPT.

RESULTS

The concentrations of ioPTH declined significantly over time in patients who received total or subtotal PTX; however, no difference was found between the two types of PTX. Irrespective of the type of PTX and the number of PTG removed, combining the absolute and percentage of ioPTH decay at 30min after PTG excision, we found high sensitivity (100%), specificity (92%), negative predictive value (100%) and accuracy (93%) in predicting the persistence of rSHPT.

CONCLUSIONS

The monitoring of the ioPTH decline by a low cost central-laboratory second generation assay is extremely accurate in predicting the persistence of disease in patients on maintenance hemodialysis undergoing surgery for rSHPT.

Safety and efficiency of microwave ablation for recurrent and persistent secondary hyperparathyroidism after parathyroidectomy: A retrospective pilot study

BACKGROUND

Recurrent and persistent secondary hyperparathyroidism (SHPT) nodules have an incidence of 10-70% after surgery. The treatment of recurrent and persistent SHPT nodules is a challenge, and surgical resection of difficult-to-reach or post-operative adhesions often fails.

PURPOSE

The aim of this research was to study the safety and effectiveness of microwave ablation (MWA) for recurrent and persistent SHPT.

MATERIALS AND METHODS

This was a retrospective study of 11 patients enrolled with a total of 16 nodules, and MWA was employed to manage SHPT. The laboratory test results, including the intact parathyroid hormone (iPTH), serum calcium, phosphorus and alkaline phosphatase (ALP) levels, improvement of SHPT-related symptoms after ablation, and complications during and after MWA were recorded and analysed.

RESULTS

After ablation the value of iPTH was markedly decreased from 1570 ± 1765 pg/mL to 287 ± 239 pg/mL 1 day after MWA (p < 0.05). The levels of serum calcium and phosphorus decreased from 2.51 ± 0.23 mmol/L to 2.06 ± 0.27 mmol/L (p < 0.001) and 1.80 ± 0.43 mmol/L to 1.48 ± 0.32 mmol/L (p < 0.05), respectively, 1 day after MWA. There was no significant difference in the ALP value before and after MWA (p > 0.05). The clinical symptoms, including ostalgia, pruritus, disability, and restless legs, improved after MWA. Minor complications and side effects encountered during or after MWA include haematoma (1/11, 9%), transient hoarseness (2/11, 18.2%), hypocalcemia (6/11, 54.5%). No major complication occurred.

CONCLUSION

MWA may be safe and effective to manage recurrent and persistent SHPT nodules; a definite conclusion needs to expand the sample size with a longer follow-up time.

Predicting postoperative total calcium requirements after parathyroidectomy in secondary hyperparathyroidism

BACKGROUND/AIMS

To prevent hypocalcemia after parathyroidectomy (PTX), parenteral calcium is required in addition to oral calcitriol and calcium. After switching to oral calcium, patients can be discharged from the hospital. The aim of this study was to analyze the clinical characteristics and outcomes of PTX performed at a single Korean center and to investigate the associated laboratory factors used to analyze the total amount of postoperative calcium required.

METHODS

We enrolled 91 hemodialysis patients undergoing PTX from November 2003 to December 2011. We collected clinical and laboratory data preoperatively, 12 and 48 hours postoperatively, at discharge, and 3 and 6 months postoperatively.

RESULTS

In total, 59 patients underwent PTX with autotransplantation (AT), 6 underwent total PTX without AT, 11 underwent subtotal PTX, and 15 underwent limited PTX. Total PTX without AT showed the lowest recurrence rate. At all postoperative time points, the mean levels of serum calcium, phosphorus, and intact parathyroid hormone (iPTH) decreased significantly, compared with preoperative levels; however, alkaline phosphatase (ALP) increased significantly from 48 hours postoperatively to discharge (p < 0.001). On multiple linear regression analysis, the total amount of injected calcium during hospitalization showed a significant correlation with preoperative ALP (p < 0.001), preoperative iPTH (p = 0.037), and Δphosphorus at 48 hours (p < 0.001). We developed an equation for estimating the total calcium requirement after PTX.

CONCLUSIONS

Preoperative ALP, preoperative iPTH, and Δphosphorus at 48 hours may be significant factors in estimating the postoperative calcium requirement. The formula for postoperative calcium requirement after PTX may help to predict the duration of postoperative hospitalization.

Outcomes of Total Parathyroidectomy with Autotransplantation versus Subtotal Parathyroidectomy with Routine Addition of Thymectomy to both Groups: Single Center Experience of Secondary Hyperparathyroidism

BACKGROUND

Secondary hyperparathyroidism is a common acquired disorder seen in chronic renal failure. It may result in potentially serious complications including metabolic bone diseases, severe atherosclerosis and undesirable cardiovascular events. Parathyroidectomy is required in about 20% of patients after 3-10 years of dialysis and in up to 40% after 20 years.

AIMS

The aim of the current study was to evaluate the short-term and long-term outcomes of patients with secondary hyperparathyroidism who had undergone total parathyroidectomy with autotransplantation and thymectomy or subtotal parathyroidectomy with thymectomy by the same surgical team during the study period.

STUDY DESIGN

Retrospective comparative study.

METHODS

Clinical data of 50 patients who underwent parathyroid surgery for secondary hyperparathyroidism between 2003 and 2011 were reviewed retrospectively. Patients were divided into two subgroups of total parathyroidectomy with autotransplantation or subtotal parathyroidectomy. Thymectomy was routinely performed for both groups. Short term outcome parameters included intact parathyroid hormone, ionized calcium and alkaline phosphatase levels. Bone pain, bone fractures, persistent or recurrent disease were included in long term outcome parameters.

RESULTS

The mean duration of dialysis was eight years. The mean ionized calcium levels dropped significantly in the total parathyroidectomy with autotransplantation group (p=0.016). No serious postoperative complications were observed. Postoperative intravenous calcium supplementation was required in four patients in the total parathyroidectomy with autotransplantation group (total PTX+AT) and in three patients in the subtotal parathyroidectomy group (subtotal PTX). Postoperatively, all patients received oral calcium carbonate and calcitriol. The length of average hospital stay was 5 (3-10) days. Including nine patients who underwent successful renal transplantation pre-operative bone symptoms, hypercalcemia, hyperphosphatemia, and an increased alkaline phosphatase levels were improved or resolved in all patients. After a mean follow-up of 65 months, three patients (6%) had persistent and one (2%) had recurrent disease.

CONCLUSION

Total parathroidectomy with autotransplantation is a beneficial and safe surgical procedure for patients on chronic dialysis with otherwise uncontrollable secondary hyperparathroidism and even in patients who have undergone renal transplantation after parathyroidectomy. Careful cervical exploration and routine thymectomy should be considered as a routine part of the surgical approach regardless of the preferred technique.

Healthcare use and costs before and after parathyroidectomy in patients on dialysis

BACKGROUND

Parathyroidectomy (PTX) is often performed in dialysis patients when medical treatment fails to control secondary hyperparathyroidism (SHPT). PTX is viewed by many as a cost-containing measure for patients who have been treated with vitamin D analogs and calcimimetics. Yet, information about health resource utilization and costs before and after PTX is limited.

METHODS

This retrospective cohort study used professional service and pharmacy claims to identify subjects on dialysis undergoing PTX from 1/1/2008-12/31/2010. Only subjects with at least six months of information before and after PTX were considered. Subjects with primary hyperparathyroidism or kidney transplant were excluded. Prescription use, physician encounters, and surgical complications were compared during the six months immediately before and after PTX.

RESULTS

The mean (SD) age of the 181 study subjects was 51 (15) years; 59% female; and 80% insured by Medicare. Overall, the percentage of patients receiving medications to manage altered mineral metabolism increased from 67% before to 79% after PTX. Specifically, oral vitamin D use increased, while the utilization of cinacalcet decreased resulting in mean (SD) monthly medication charges decreasing from $486 (507) to $226 (288) (p < 0.01). The mean (SD) number of physician encounters rose from 15 (14) before to 21 (22) per 6 months after PTX (p < 0.01) resulting in the corresponding increase in mean (SD) monthly charges from $1531 (2150) to $1965 (3317) (p = 0.08). Hypocalcemia was the predominant diagnosis recorded for post-surgical physician encounters occurring in 31% of all subjects; 84% of hypocalcemic episodes were managed in acute care facilities.

CONCLUSIONS

The cost of medications to manage SHPT decreased after PTX largely due to reduction in cinacalcet use, whereas vitamin D use increased likely to manage hypocalcemia. The frequency and cost of physician encounters, especially in acute care settings, were higher in the 6 months after PTX attributable largely to episodes of severe hypocalcemia. Overall, the reduction in prescription costs during the 6 months after PTX is outweighed by the higher costs associated with physician care.

Efficacy of intraoperative parathyroid hormone monitoring to predict success of parathyroidectomy for secondary hyperparathyroidism

Purpose

In secondary hyperparathyroidism (sHPT), it is unclear which criterion for intraoperative parathyroid hormone (ioPTH) decline performs best and whether ioPTH monitoring is sufficiently efficacious in predicting postoperative surgical cure by retrospective review.

Methods

In 80 parathyroidectomies for sHPT, patients with ioPTH monitoring and follow-up PTH assay were categorized into physiologically accepted and failed groups. Receiver operating characteristic (ROC) curves were used to identify the criterion with the best performance and to determine the regression equation for prediction of surgical success.

Results

There was a statistically significant difference in the percentage reduction of ioPTHs between the two groups (P < 0.05). With our criterion, cure was predicted with a sensitivity of 86% and specificity that could be improved to 60% using an 85% ioPTH decrease as cut-off level when this value was compared to the Miami Criterion. There was a slightly negative correlation between the natural logarithm of percentage reduction of ioPTH and percentage reduction of PTH at follow-up (R² = 0.109, P = 0.003).

Conclusion

ioPTH measurements are a useful tool for improvement of the cure rate of operations for sHPT. Because this study aimed at 40 minutes (ioPTH3) as an optimal process in the operation, we recommend using a criterion of more than 85% ioPTH decline at 40 minutes by use of the ROC curve, and the use of the presently calculated regression equation may enable prediction of success.

Frequency of ectopic and supernumerary intrathymic parathyroid glands in patients with renal hyperparathyroidism: analysis of 461 patients undergoing initial parathyroidectomy with bilateral cervical thymectomy

BACKGROUND

The frequency of intrathymic parathyroid glands (IPGs) in patients undergoing parathyroidectomy for renal hyperparathyroidism (rHPT) varies considerably between 14.8% and 45.3%. Total parathyroidectomy with autotransplantation and subtotal parathyroidectomy are the most accepted surgical procedures to treat patients with rHPT. However, routine bilateral cervical thymectomy (BCT) is still discussed, although controversially.

METHODS

From a prospective database of patients who underwent parathyroid surgery for rHPT between 1975 and 2009, patients with routine BCT at initial PTX were further analyzed regarding the frequency of ectopic and supernumerary IPGs. Duration of hemodialysis and stage of chronic kidney disease were correlated with the frequency of supernumerary IPGs to elucidate a potential role of long-standing proliferation stimuli to any surplus parathyroid tissue.

RESULTS

Initial parathyroidectomy with BCT was performed in 461 patients. IPGs were resected in 205 of them (44.5%). They were ectopic in 181 (39.3%) and supernumerary in 30 patients (6.5%). The frequency of supernumerary IPGs in patients on permanent hemodialysis was 7.4% (29/392), 3.9% (1/26) in predialysis patients, and 0% (0/43) in patients after successful kidney transplantation. This differences reached no statistical significance.

CONCLUSIONS

BCT is essential in patients with fewer than four parathyroid glands identified at typical positions. Because of the low frequency of supernumerary IPGs and a suspected low proliferation stimulus, the relevance of BCT after resection of four glands in predialysis patients and those after successful kidney transplantation must be questioned. Nevertheless, routine BCT seems to be acceptable and can be recommended in patients on permanent hemodialysis not awaiting kidney transplantation until proven otherwise by prospective trials.

[Surgical treatment of secondary hyperparathyroidism in patients with chronic renal failure]

OBJECTIVE

To identify the indications for subtotal parathyroidectomy (PTX) in secondary hyperparathyroidism (SHPT) and report postoperative, early and late complications of PTX.

PATIENTS AND METHODS

We conducted a retrospective study of subjects with chronic renal failure operated in Tunisian hospitals who received subtotal PTX over 10 years from January 1997 to December 2007. We analyzed the clinical, biological and radiological parameters pre- and postoperatively.

RESULTS

We included 70 patients with average age of 39.4 years, 55.7% men and 44.3% in dialysis for 7.75 ± 4.8 years before PTX. The initial nephropathy was interstitial in 50% of cases. No cases of diabetic nephropathy have been reported. The clinical signs were bone pain (88.6%), muscle pain (85.6%), pruritus (81.4%). Radiological signs of osteitis fibrosa were observed in the majority of patients mainly resorption of extremities (92.9%), thinning of cortical (85.7%) and osteosclerosis (87.1%). The most common indication of PTX (85.7% of cases) was the persistence of serum PTH of more than 800 pg/ml associated with hypercalcemia and/or hyperphosphatemia refractory to medical treatment. A subtotal PTX (3/4 or 7/8) was performed after ultrasound and scintigraphy in the majority of cases. The histology of the parathyroid glands showed diffuse hyperplasia (51.4%), nodular hyperplasia (45.7%) and adenoma (2.8%). The postoperative evolution was marked by an improvement of the clinical and radiological criteria in 80% of cases. A PTH level of less than 15 pg/ml was rarely observed (10% of cases), and a PTH level of more than 300 pg/ml concerned 13% of patients. We noted a low morbidity and mortality (no cases laryngeal paralysis or cervical hematoma).

CONCLUSION

Surgical treatment of SHPT in Tunisia is very effective in our experience. The biological results are comparable to treatment with calcimimetics, not available in Tunisia and whose price is higher. An early treatment of disorders of bone and mineral metabolism should reduce the incidence of SHPT.

Cryopreservation of parathyroid glands

The risk of permanent hypoparathyroidism following thyroid and parathyroid surgery is around 1% in the hands of experienced endocrine surgeons. Although this complication is rare, rendering a patient permanently aparathyroid has significant consequences on the health and quality of life of the patient. Immediate autotransplantation of parathyroid glands that are injured or unintentionally removed offers the best possibility of graft viability and functionality. However, since the majority of cases of hypoparathyroidism are transient, immediate autotransplantation can complicate postoperative surveillance in certain patients, especially those with primary hyperparathyroidism. Cryopreservation of parathyroid tissue is an alternate technique that was developed to treat patients with permanent hypoparathyroidism. This method allows for parathyroid tissue to be stored and then autotransplanted in a delayed fashion once permanent hypoparathyroidism is confirmed. This article provides a contemporary review on cryopreservation of parathyroid tissue and its current role in thyroid and parathyroid surgery.