Primärer Hyperparathyreoidismus

Introduction

Normocalcemic hyperparathyrinemia, i.e. elevated parathyroid hormone (PTH) levels after parathyroidectomy in patients with primary hyperparathyroidism (pHPT) may occur in the course of postoperative recovery without the development of persistence or relapse.

Materials, methods and results

Intraoperative and long-term (7 year) postoperative PTH and calcium levels after curative parathyroidectomy are demonstrated on the basis of a case report of a 62-year-old female patient with severe pHPT and pronounced osseous and renal manifestations. The intraoperative PTH gradient displayed a decrease from 1072 pg/ml to 13 pg/ml (normal range 11–67 pg/ml) followed by an increase of up to 287pg/ml. The hyperparathyoid values decline to subnormal levels on administration of calcium and vitamin D and increase again after tapering these medications. The inverse calcium/PTH correlation in the course of the 7-year observation period suggests an intact feed-back mechanism. Preoperative PTH screening was performed in 316 consecutive normocalcemic thyroid patients to evaluate the rate of incidental hyperparathyroidism in patients with normal serum calcium levels. Of these patients 31 (9.8%) with normocalcemia (average 2.28 mmol/l, normal range 2.1–2.7 mmol/l) exhibited increased PTH levels averaging 84.2 pg/ml. A parathyroid adenoma was found intraoperatively as the cause for normocalcemic pHPT in only 1 of these 31 patients.

Discussion and conclusions

A review of the literature revealed that late postoperative elevated parathyroid hormone levels after successful pHPT surgery occur in 21.5%. Multiple causes are discussed, e.g. reactive hyperparathyroidism in cases of relative hypocalcemia, hungry bone syndrome, vitamin D deficiency, renal dysfunction and ethnic or lifestyle differences. In mild cases of postoperative hyperparathyrinemia observation of the patient may be sufficient. In cases of reactive hyperparathyroidism due to hypocalcemia, administration of calcium is indicated, in symptomatic patients, additional administration of vitamin D or calcitriol is necessary. Vitamin D deficiency per se needs adequate substitution. In cases of ongoing hyperparathyrinemia an interdisciplinary diagnostic and therapeutic approach is required.     

Intraoperative Secretion of Intact Parathyroid Hormone and Amino-Terminal Parathyroid Hormone Fragments from Normal Parathyroid Glands Associated with Solitary Parathyroid Adenoma

p < 0.05 for both). Because the reduction was more pronounced for i-PTH than for N-PTH, the N/i ratio increased from 0.54 ± 0.33 to 3.76 ± 1.62 ( p < 0.05). Furthermore, the levels of i-PTH and N-PTH were higher centrally than peripherally both before and after adenoma excision ( p < 0.05). The results therefore suggest that the secretion of i-PTH and N-PTH in the remaining normal-size parathyroid glands is not completely suppressed. Furthermore, in these parathyroid glands the secretion of amino-terminal PTH fragments is relatively predominant when compared to the release of the intact PTH. The findings underscore the importance of the N-terminal PTH fragment for maintaining calcium homeostasis during the early postoperative period after surgery for pHPT and may explain the rarity of prolonged hypocalcemia after parathyroidectomy.     

Primary hyperparathyroidism after radioactive iodine therapy: Is it a distinct clinical entity?

BackgroundRadioactive iodine (RAI) treatment is considered a rare cause of primary hyperparathyroidism (pHPT).MethodA multi-institutional retrospective review of patients with pHPT who underwent parathyroidectomy from 1990 to 2020 was completed to evaluate the prevalence and latency time for development of RAI-associated pHPT and determine clinical differences in pHPT patients with or without prior RAI treatment.Results1929 patients with sporadic pHPT underwent parathyroidectomy; 48 (2.5%) had prior RAI treatment and 1881 (97.5%) did not. RAI treatment was for thyrotoxicosis in 43 (90%) patients. Average latency was 24 years (3–59 years) and inversely correlated with age. Patients with prior RAI treatment had lower preoperative calcium and PTH levels (p < 0.0001). No significant differences were observed in age, symptoms, pathology, ectopic glands and cure rate.ConclusionRAI is a potential causative factor for pHPT, accounting for 2.5% of sporadic pHPT. RAI-associated pHPT may be a less severe form of sporadic pHPT and latency inversely correlates with age.     

Incremento de la densidad mineral ósea en pacientes con hiperparatiroidismo terciario tras paratiroidectomía total y autotrasplante de glándula paratiroides

IntroductionChanges in bone metabolism and bone mineral density are observed in renal transplant patients with tertiary hyperparathyroidism. The objective of this work was to analyse the increase in bone mineral density, as well the laboratory results, after total parathyroidectomy and autotransplantation in renal transplant patients with tertiary hyperparathyroidism.Material and methodsA retrospective study was conducted in which the bone mineral density values at femoral and lumbar level were analysed, together with the serum levels of calcium, phosphorous, parathyroid hormone (PTH), and alkaline phosphatase in 13 renal transplant patients with tertiary hyperparathyroidism before and after total parathyroidectomy and autotransplantation of the parathyroid glands.ResultsParathyroidectomy is associated with an increase in bone mineral density at femoral and lumbar level, with an increase of 8.6 ± 6.7% at lumbar level, and 4 ± 16.1% at femoral level. The decrease in calcium after the parathyroidectomy was 2.8 mg/dL (95% CI; 1.9-4). The decrease in PTH was 172 pg/mL (95% CI; 98-354) and the decrease in alkaline phosphatase was 229 U/L (95% CI; 70-371).ConclusionsTotal parathyroidectomy and autotransplantation of the parathyroid glands in renal transplant patients with tertiary hyperparathyroidism increases the bone mineral density. Furthermore, the calcium, PTH and alkaline phosphatase returned to normal in the long-term.     

Utility of Intraoperative Parathyroid Hormone Monitoring in Patients with Multiple Endocrine Neoplasia Type 1-Associated Primary Hyperparathyroidism Undergoing Initial Parathyroidectomy

Background

Intraoperative parathyroid hormone monitoring (IOPTH) is a widely used adjunct for primary hyperparathyroidism (pHPT). However, the benefit of IOPTH in familial pHPT, such as in multiple endocrine neoplasia type I (MEN1), remains unclear.

Methods

We performed a retrospective analysis of 52 patients with MEN1-associated pHPT undergoing initial parathyroidectomy with IOPTH monitoring at our institution. Parathyroid hormone (PTH) levels were measured before skin incision and 10 min after resection of the last parathyroid gland. Variables analyzed included percent drop of PTH from baseline and the final PTH level compared to the normal reference range (RR).

Results

A total of 52 patients underwent initial subtotal parathyroidectomy with IOPTH. An IOPTH decrease cutoff of ≥75 % from baseline had the highest biochemical cure rate (87 %). In the remaining 13 % who met this cutoff, all had persistent pHPT, with ≥90 % drop of PTH from baseline. The remaining patients, who did not meet the ≥75 % cutoff, were cured. Follow-up was available for three of four patients with final IOPTH levels above the RR: one had persistent pHPT, two had hypoparathyroidism (50 %). When a postresection PTH level was within the RR, 88 % of patients were cured. While considered cured from pHPT, 7 % of patients in this group developed permanent hypoparathyroidism. When the final PTH level dropped below the RR, 28 % developed permanent hypoparathyroidism.

Conclusions

A cutoff in IOPTH decrease of ≥75 % from baseline has the highest biochemically cure rate in patients with pHPT associated with MEN1. However, a 75 % cutoff in IOPTH decrease does not exclude persistent pHPT. The absolute IOPTH value does not accurately predict postoperative hypoparathyroidism.     

Hypercalcemia with a parathyroid hormone level of ≤50 pg/mL: Is this primary hyperparathyroidism?

BackgroundPrimary hyperparathyroidism is characterized by hypercalcemia with inappropriately normal or elevated parathyroid hormone. However, the absolute parathyroid hormone value that is defined as inappropriately normal is unclear. We reviewed our experience with parathyroidectomy in patients with hypercalcemia and parathyroid hormone of ≤50.0 pg/mL (normal range 12.0–88.0 pg/mL).MethodsA total of 2,349 patients underwent parathyroidectomy for primary hyperparathyroidism between 2000 and 2021. Of these, 149 patients had preoperative parathyroid hormone ≤50.0 pg/mL (parathyroid hormone ≤50). The biology and outcomes were compared to patients with parathyroid hormone >50.0 pg/mL (parathyroid hormone >50).ResultsOf the parathyroid hormone ≤50 patients, the median parathyroid hormone was 40.0 pg/mL (range 11.6–50.0 pg/mL). All patients were found to have abnormal hypercellular parathyroid glands with a cure rate of 96.7%. When compared to the parathyroid hormone >50 group, the parathyroid hormone ≤50 group was younger (56 ± 15 vs 60 ± 14 years, P < .001) with a lower body mass index (28.7 ± 7.0 kg/m² vs 31.2 ± 7.9 kg/m², P < .001), higher rate of fatigue (73.2% vs 63.0%, P = .033), and higher rate of multiglandular disease (58.9% vs 31.9%, P < .001). There was no difference between the groups with respect to patient demographics, rate of previous parathyroidectomy, surgical cure, or postoperative complications (persistent or recurrent hyperparathyroidism and hypocalcemia).ConclusionPatients with hypercalcemia and parathyroid hormone ≤50 pg/mL have a similar clinical presentation and rate of surgical cure to other primary hyperparathyroidism patients and should be considered for parathyroidectomy. Most of these patients have multiglandular disease and thus should be considered for bilateral parathyroid exploration.     

Dynamics of Parathyroid Hormone Secretion After Total Parathyroidectomy and Autotransplantation

Background  Secondary hyperparathyroidism is a common complication in uremic patients. Total parathyroidectomy combined with partial autotransplantation into brachioradialis muscle has been the preference among the options for surgical treatment. This study was designed to evaluate the reserve and ability of suppression of autotransplanted parathyroid tissue using dynamics tests. Methods  We studied, prospectively, 12 patients in recent (RP) and late (LP) postoperative of total parathyroidectomy with autotransplantation. For analysis of the secretory reserve capacity, we induced hypocalcemia by ethylenediaminetetraacetic acid (EDTA) infusion. Furthermore, for analysis of the ability for parathyroid hormone (PTH) suppression, the hypercalcemia test was used, by intravenous administration of calcium in LP. Results  In RP, there was a decrease in the average serum levels of PTH, phosphorus, and alkaline phosphatase, which ranged from 13 to 231 (87 ± 65) pg/ml, 2.3 to 6.2 (3.3 ± 1.1) mg/dl, and 77 to 504 (250 ± 135) U/L, respectively, similar to that observed in LP. The analysis of the average curve of variations in PTH during testing of the stimulus with EDTA showed lack of secretion in RP and partial response in LP. Impaired suppression ability of the graft in LP was observed in the test with intravenous calcium. Conclusions  Total parathyroidectomy followed by partial autotransplantation was effective in reducing PTH serum levels in patients with terminal kidney disease. The elevation of serum calcium during the suppression test was not able to inhibit the autograft gland secretion of PTH. The assessment of parathyroid graft function demonstrated an inability to respond to the stimulus of hypocalcemia induced by EDTA, although there was a partial recovery, in late postoperative period.     

Hiperparatiroidismo primario y crisis hipercalcémica aguda tóxica

ObjectivesTo describe the clinical characteristics and surgical treatment of patients with acute hypercalcaemia due to primary hyperparathyroidism (PHPT) and compare them with other patients with PHPT without associated acute hypercalcaemia.Material and methodsA prospective, observational study (1998-2010) was conducted on 158 patients with PHPT treated by parathyroidectomy. Those with acute hypercalcaemia (>14 mg/dl -3.5 mmol/L- or >3 mmol/L with symptoms of calcium toxicity) were evaluated by recording their clinical and treatment characteristics, and comparing them, using the Mann-Whitney U test and the Fisher test, with the 146 PHPT patients without hypercalcaemic crisis.ResultsTwelve patients (7.6%) had acute hypercalcaemia with symptoms of calcium toxicity and other symptoms of chronicity. The preoperative calcium and PTH values were 14.5 ± 1.3 mg/dL and 648.2 ± 542 pg/dL, respectively. There were 10 adenomas, 1 hyperplasia and 1 carcinoma. The mean weight of the surgical pieces was 4.075 ± 2.918 mg, with a diameter greater than 27 ± 14 mm. The gradients of PTH at 10 and 25 minutes were 79 ± 18% and 92 ± 6%, respectively. Post-operative calcium values on discharge and at 6 months were 8.2 ± 0.7 mg/dL and 9.1 ± 0.9 mg/dL, respectively. The plasma concentrations of calcium, PTH, and the size of the surgical pieces were higher in patients with hypercalcaemic crisis (P<0.001). There were no differences in the other parameters studied or in the cure rate.ConclusionsHypercalcaemic crises were caused by larger and heavier tumours that led to higher plasma Ca and PTH plasma concentrations. All patients had long-standing symptoms and parathyroidectomy led to cure of the disease.     

Sporadic and MEN1‐Related Primary Hyperparathyroidism: Differences in Clinical Expression and Severity

Primary hyperparathyroidism (PHPT) is a common endocrine disease that is associated with multiple endocrine neoplasia type 1 (MEN1) in ～2% of PHPT cases. Lack of a family history and other specific expressions may lead to underestimated MEN1 prevalence in PHPT. The aim of this study was to identify clinical or biochemical features predictive of MEN1 and to compare the severity of the disease in MEN1‐related versus sporadic PHPT (sPHPT). We performed a 36‐mo cross‐sectional observational study in three tertiary referral centers on an outpatient basis on 469 consecutive patients with sporadic PHPT and 64 with MEN1‐related PHPT. Serum calcium, phosphate, PTH, 25(OH)D₃, and creatinine clearance were measured, and ultrasound examination of the urinary tract/urography was performed in all patients. In 432 patients, BMD was measured at the lumbar spine (LS) and femoral neck (FN). MEN1 patients showed lower BMD Z‐scores at the LS (?1.33 ± 1.23 versus ?0.74 ± 1.4, p = 0.008) and FN (?1.13 ± 0.96 versus ?0.6 ± 1.07, p = 0.002) and lower phosphate (2.38 ± 0.52 versus 2.56 ± 0.45 mg/dl, p = 0.003) and PTH (113.8 ± 69.5 versus 173.7 ± 135 pg/ml, p = 0.001) levels than sPHPT patients. Considering probands only, the presence of MEN1 was more frequently associated with PTH values in the normal range (OR, 3.01; 95% CI, 1.07–8.50; p = 0.037) and younger age (OR, 1.61; 95% CI, 1.28–2.02; p = 0.0001). A combination of PTH values in the normal range plus age <50 yr was strongly associated with MEN1 presence (OR, 13.51; 95% CI, 3.62–50.00; p = 0.0001). In conclusion, MEN1‐related PHPT patients show more severe bone but similar kidney involvement despite a milder biochemical presentation compared with their sPHPT counterparts. Normal PTH levels and young age are associated with MEN1 presence.     

原发性甲状旁腺功能亢进症的外科治疗

目的　总结原发性甲状旁腺功能亢进症的外科治疗经验。方法　回顾性分析 1985～2 0 0 2年在我科行外科手术治疗的 5 5例原发性甲状旁腺功能亢进症患者的临床资料。全组病例均行甲状旁腺切除术。结果　 5 5例患者中无症状者 8例 ,骨、关节病变 2 4例 ,泌尿系结石病变 10例 ,骨和泌尿系结石病变 13例 ,病理性骨折 16例。全组血钙均升高 ,在 2 7～ 3 9mmol/L之间 ,平均 (3 1± 0 4 )mmol/L。 5 0例患者术前测定甲状旁腺激素升高在 10 2～ 2 0 0 0pg/ml之间 ,平均 (489 2±6 9 2 ) pg/ml。联合B超、CT、核素扫描术前定位诊断率达 90 9%。术后全组均随访 6个月～ 2年 ,术后临床表现缓解 ,骨质疏松改善 ,骨折愈合 ,有 39例患者出现短期低血钙 ,37例出现面部、手足麻木 ,10例出现手足抽搐。术后有 15例患者血钙正常 ,1例略高于正常值 ,低血钙者经骨化三醇和钙剂治疗 1～ 3周均可改善 ,血钙恢复正常。术后 4 7例患者甲状旁腺激素均在 2个月内恢复到正常 ,3例略高于正常值。结论　甲状旁腺切除术是治疗原发性甲状旁腺功能亢进症的有效方法。经术前影像学定位后行小范围、小创伤的甲状旁腺切除术是可行的手术方法。及时将原发性甲状旁腺功能亢进症患者转入内分泌外科治疗可达到早期治疗、减少骨关节和泌     

Outcomes of Parathyroid Autotransplantation During Total Thyroidectomy: A Comparison with Age- and Sex-Matched Controls

Purpose: To determine the effect of parathyroid autotransplantation (PA) on postoperative hypocalcemia in cases of total thyroidectomy. Materials and Methods: Cases undergoing total thyroidectomy and PA were compared with age and sex-matched controls who had not undergone PA. The postoperative percentage changes (PC) of parathyroid hormone (PTH) and calcium (Ca+2) in the first 12–24 hours (12–24hr→preop), between the 1st-3rd weeks (1-3wk→preop) and at the 6th month (6mo→preop), the rates of hypocalcemia (Ca+2< 8mg/dL) and low PTH level (PTH< 15 pg/mL), permanent hypocalcemia, inadvertent parathyroidectomy in both groups were compared. Results: The number of patients with PTH12-24hr<15 pg/mL was significantly higher (n:34,(55.7%)) than the number of patients in the control group (n:16(26.2%)), (p=0.001). The rate of decrease in the blood Ca+2 median PC (6mo→preop) was significantly higher in the PA group (4.2%) than the control group (1.1%), (p=0.008). There was no significant difference between the 2 groups in terms of the postoperative frequency of hypocalcemia (p>0.05). In the PA&age≤50 group, the rate of inadvertent parathyroidectomy was higher than that of cases over age 50 (p=0.029). Conclusion: In spite of the presence of an increased postoperative hypocalcemia trend in cases requiring PA during total thyroidectomy, the rates of transient and permanent hypocalcemia were not different to the control cases. But the frequency of cases with low PTH level in cases undergoing PA was higher than that of the control cases. In cases of 50 years of age and under, who had undergone PA, the possibility of inadvertent parathyroidectomy increased.     

Class 3 obesity is not associated with same-day admission in obese patients undergoing parathyroidectomy

ImportanceRising rates of obesity and outpatient performance of parathyroidectomies are making it increasingly crucial to investigate the association of obesity with post-operative complications.ObjectiveTo determine whether Class 3 obesity is associated with increased same-day admission compared to lower obesity classes following outpatient parathyroidectomy.DesignRetrospective cohort study.SettingOutpatient surgery.Patients12,973 patients ≥18 years old who underwent outpatient parathyroidectomy between 2014 and 2016, per the American College of Surgeons National Surgical Quality Improvement Program registry.InterventionsPrimary exposure variable: body mass index (BMI), with patients assigned to one of six cohorts.MeasurementsPrimary outcome measure: same-day admission. Secondary outcome measure: 30-day readmission. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI).Main resultsThere was a final sample size of 12,973 adult patients who underwent parathyroidectomy from 2014 to 2016. The admission rate for BMI ≥30 and < 40 kg/m² (reference cohort) was 42.6%. The admission rates for Class 3 obesity categories were 46.2%, 56.2%, and 52.6% for those in the BMI range of ≥40 kg/m² and < 50 kg/m², ≥50 kg/m² and < 60 kg/m², and ≥ 60 kg/m², respectively. On multivariable logistic regression, there were no difference in the odds of 30-day hospital admission or readmission rate with any of the BMI cohorts when compared to the reference group.ConclusionsThere is no significant difference in rates of same-day admission or 30-day readmission between any Class 3 (BMI ≥40 kg/m²) obesity cohort and the Class 1 and 2 (BMI ≥30 and < 40 kg/m²) reference cohort following outpatient parathyroidectomy. This corroborates the notion that BMI classes cannot be used in a vacuum to determine eligibility for outpatient parathyroidectomy – a concept that can guide safe and cost-effective institutional practices.     

Fibroblast Growth Factor–23 Levels Are Associated With Uric Acid But Not Carotid Intima Media Thickness in Renal Transplant Recipients

IntroductionCardiovascular disease (CVD) is the leading cause of mortality in chronic kidney disease (CKD) patients. Fibroblast growth factor–23 (FGF-23) is associated with atherosclerosis and cardiovascular mortality in CKD patients and healthy subjects. However, data in renal transplant recipients (RTR) are scarce. We aimed to determine factors associated with FGF-23 and to explore its relationship to atherosclerosis.MethodsForty-six patients and 44 controls were included. FGF-23 was measured from plasma. Carotid intima media thickness (CIMT) was evaluated ultrasonographically.ResultsPatients had higher waist circumference (WC; 92.2 ± 14.9 vs 85.3 ± 11.0 cm; P < .05), glucose (99.8 ± 17.2 vs 90.3 ± 6.5 mg/dL; P < .01), creatinine (1.43 ± 0.6 vs 0.86 ± 0.1 mg/dL; P < .01), triglyceride (160.4 ± 58.9 vs 135.6 ± 59.8 mg/dL; P < .05), white blood cells (WBC; 7938.6 ± 2105.2 vs 6715.7 ± 1807.5 WBC/mm³; P < .01), ferritin (217.0 ± 255.8 vs 108.3 ± 142.4 ng/mL; P < .05), uric acid (6.5 ± 1.6 vs 4.7 ± 1.3 mg/dL; P < .01), C-reactive protein (CRP; 8.2 ± 18.2 vs 5.3 ± 7.9 mg/L; P < .01), parathyroid hormone (PTH; 89.7 ± 59.2 vs 44.1 ± 16.7 pg/mL; P < .01), and alkaline phosphatase (ALP; 162.5 ± 86.6 vs 74.2 ± 21.9 U/L; P < .01). FGF-23 was higher in patients (11.7 ± 7.2 vs 9.6 ± 6.8 pg/mL; P < .05). CIMT was similar (0.58 ± 0.09 vs 0.57 ± 0.1 mm; P > .05). WC, creatinine, and uric acid were positively correlated with FGF-23, whereas albumin showed negative correlation. On multivariate analysis only creatinine and uric acid were determinants of FGF-23.ConclusionFGF-23 levels are associated with uric acid in RTR. Larger studies are needed to confirm this finding.     

Preoperative localizing studies for initial parathyroidectomy in MEN1 syndrome: is there any benefit?

Background  

The objective of the present study was to evaluate the utility of preoperative localizing studies in patients with MEN1 undergoing initial bilateral neck exploration (BNE) and parathyroidectomy for pHPT.     

Surgical Treatment of Patients with Mildly Elevated Parathormone and Calcium Levels

Background

Patients with mildly elevated parathormone (PTH) and calcium levels consistent for primary hyperparathyroidism (pHPT) may present with more underlying multiglandular disease (MGD) and higher operative failure and recurrence rates than those with conventional, or “classic” pHPT. This study compared the clinical characteristics and surgical outcomes of patients with biochemically mild versus conventional pHPT.

Methods

A series of 707 consecutive patients underwent initial targeted parathyroidectomy with intraoperative parathormone monitoring (IPM) at a single institution. Biochemically mild (BM) pHPT was defined as PTH > 65 and <100 pg/ml with serum calcium >10.4 and <11 mg/dl. Conventional pHPT was defined as calcium ≥11 mg/dl and PTH ≥ 100 pg/ml. Prospectively collected data for all patients, including operative indication, preoperative laboratory values, imaging, IPM dynamics, and postoperative laboratory values were retrospectively reviewed. Additional assessments included presence of MGD, bilateral neck exploration (BNE), single-gland volume, and operative failure or success, and recurrence.

Results

Of 60 patients with BM-pHPT, 46 reported preoperative bone pain, kidney stones, fatigue, and/or mental disturbances. The remaining 14 BM-pHPT patients underwent parathyroidectomy based on published asymptomatic guidelines. Patients with BM-pHPT had significantly more kidney stones, MGD, and BNE. Average single-gland volume and postoperative PTH levels were significantly lower in BM-pHPT patients. There were no significant differences between groups regarding preoperative localization accuracy, IPM dynamics, or operative success/failure, recurrence rates.

Conclusions

BM-pHPT patients had more MGD requiring BNE but achieved operative success rates similar to those of patients with conventional disease. IPM successfully identifies MGD in BM-pHPT patients, who should be counseled regarding more extensive operations than limited parathyroidectomy.     

Effect of Cinacalcet in Kidney Transplant Patients With Hyperparathyroidism

ObjectiveIn dialysis patients, cinacalcet could be an effective alternative to parathyroidectomy for treating hyperparathyroidism. In the present study, we aimed to determine the characteristics of subjects with persistent hyperparathyroidism who require parathyroidectomy despite the use of cinacalcet.MethodsNine kidney transplant patients (7 men, 2 women; mean age 53.2 [SD, 8.9] years) who had tertiary hyperparathyroidism were reviewed in a single center. Pre- and postcinacalcet levels of calcium, phosphorous, intact parathyroid hormone (iPTH), and renal function were analyzed to evaluate the effect of cinacalcet treatment in these patients. The baseline parameters before cinacalcet treatment were compared in patients who did and did not undergo parathyroidectomy.ResultsCinacalcet reduced serum calcium levels in all patients (11.48 [SD, 0.73] mg/dL to 10.20 [0.70] mg/dL; P = .008). Serum phosphorous levels significantly increased from 2.28 (SD, 0.77) mg/dL to 3.02 (SD, 0.65) mg/dL (P = .03). The iPTH levels in 7 patients decreased, while the mean level remained unchanged in total subjects. The iPTH levels increased even with cinacalcet treatment in 2 patients. In 3 patients, serum calcium levels abruptly increased after cinacalcet withdrawal. Five patients who showed persistent hypercalcemia due to hyperparathyroidism underwent parathyroidectomy. These 5 patients had significantly different characteristics compared with 4 patients who did not undergo parathyroidectomy: hypercalcemia (11.92 [SD, 0.68] mg/dL vs 10.93 [SD, 0.26] mg/dL; P = .02), hypophosphatemia (1.74 [SD, 0.36] mg/dL vs 2.95 [SD, 0.58] mg/dL; P = .03), and hyperparathyroidism (252.2 [SD, 131.4] pg/dL vs 101.5 [SD, 18.4] pg/dL; P = .02).ConclusionCinacalcet reduced hypercalcemia due to hyperparathyroidism in the transplant patients. However, patients who had pre-existing higher iPTH, hypercalcemia, and hypophosphatemia needed parathyroidectomy. Therefore, cinacalcet could be considered an alternative to parathyroidectomy in selected patients.     

Incidental parathyroidectomy in thyroidectomy and central neck dissection

BackgroundAlthough higher thyroidectomy volume has been linked with lower complication rates, its association with incidental parathyroidectomy remains less studied. The volume relationship is even less clear for central neck dissection, where individual parathyroid glands are at greater risk.MethodsPatients undergoing thyroidectomy with or without central neck dissection were evaluated for incidental parathyroidectomy, hypoparathyroidism, and hypocalcemia. Univariate and multivariable analyses were performed using binary logistic regression.ResultsOverall, 1,114 thyroidectomies and 396 concurrent central neck dissections were performed across 7 surgeons. Incidental parathyroidectomy occurred in 22.4% of surgeries (range, 16.9%–43.6%), affecting 7.1% of parathyroids at risk (range, 5.8%–14.5%). When stratified by surgeon, lower incidental parathyroidectomy rates were associated with higher thyroidectomy volumes (R² = 0.77, P = .008) and higher central neck dissection volumes (R² = 0.93, P < .001). On multivariable analysis, low-volume surgeon (odds ratio 2.94, 95% confidence interval 2.06–4.19, P < .001), extrathyroidal extension (odds ratio 3.13, 95% confidence interval 1.24–7.87, P = .016), prophylactic central neck dissection (odds ratio 2.68, 95% confidence interval 1.65–4.35, P <.001), and therapeutic central neck dissection (odds ratio 4.44, 95% confidence interval 1.98–9.96, P < .001) were the most significant factors associated with incidental parathyroidectomy. In addition, incidental parathyroidectomy was associated with a higher likelihood of temporary hypoparathyroidism (odds ratio 2.79, 95% confidence interval 1.45–5.38, P = .002) and permanent hypoparathyroidism (odds ratio 4.62, 95% confidence interval 1.41–5.96, P = .025), but not permanent hypocalcemia (odds ratio 1.27, 95% confidence interval 0.48–3.35, P = .63). Higher lymph node yield in central neck dissection was not associated with higher incidental parathyroidectomy rates (odds ratio 1.13, 95% confidence interval 0.85–8.81, P = .82).ConclusionHigher surgical volume conferred a lower rate of incidental parathyroidectomy. Nonetheless, greater lymph node yield in central neck dissections did not result in greater parathyroid-related morbidity. Such findings support the value of leveraging surgical volume to both optimize oncologic resection and minimize complication rates.     

Serum Magnesium Measurements After Parathyroidectomy for Primary Hyperparathyroidism: Should It be Routine?

Background

Parathyroidectomy is the treatment of choice in primary hyperparathyroidism (PHPT). Following surgery, significant changes in bone and mineral metabolism may follow, but routine magnesium monitoring is not standard practice. The occurrence of significant clinical events linked to hypomagnesaemia in 3 patients after parathyroidectomy led to our evaluation of magnesium levels after surgery for PHPT.

Methods

Serum magnesium levels before and after parathyroidectomy for PHPT were prospectively evaluated in a single centre over a year. The incidence and severity of hypomagnesaemia and its correlation with other biochemical variables were assessed.

Results

A total of 138 patients underwent parathyroidectomy for PHPT. Pre-operative and day 1 post-operative serum magnesium levels were available in 57/138 (41.3%) and 99/138 (71.7%) patients, respectively. Serum magnesium decreased significantly after surgery (mean ± SD of 0.85 ± 0.08 and 0.75 ± 0.11 mmol/L, respectively, p < 0.001). On the day after parathyroidectomy, 31/99 (31.3%) patients had hypomagnesaemia (<0.70 mmol/L); in 3 of whom it was severe (<0.50 mmol/L). Patients with hypomagnesaemia had lower pre-operative magnesium (mean ± SD of 0.78 ± 0.06 and 0.87 ± 0.07 mmol/L, p < 0.001), higher pre-operative calcium [median (IQR) of 2.83 (2.71–2.99) and 2.71 (2.63–2.80) mmol/L, p = 0.001] and higher post-operative calcium [median (IQR) of 2.41 (2.30–2.51) and 2.35 (2.28–2.43) mmol/L, p = 0.046] compared to those with normomagnesaemia. In addition, these patients demonstrated higher drop in calcium levels after surgery (0.44 ± 0.20 and 0.35 ± 0.18 mmol/L, p = 0.033). Magnesium levels after surgery correlated positively with pre-operative magnesium (r = 0.561, p < 0.001) and post-operative PTH (r = 0.210, p = 0.037) and negatively with pre-operative adjusted calcium (r = − 0.389, p < 0.001).

Conclusions

Serum magnesium decreased significantly following parathyroidectomy for PHPT and nearly a third of patients developed post-operative, mostly mild hypomagnesaemia. Whilst routine serum magnesium measurements could facilitate prompt recognition and treatment of this electrolyte disturbance, further research needs to establish the clinical importance of mild hypomagnesaemia in these clinical settings and, if indicated, to devise optimal treatment strategies.

     

A patient undergoing chronic dialysis whose renal anemia was successfully corrected by treatment with cinacalcet

A 62-year-old female dialysis patient with chronic glomerulonephritis had been receiving hemodialysis therapy for 32 years. In 1985 she underwent a parathyroidectomy for secondary hyperparathyroidism (HPT); however, her parathyroid hormone (PTH) levels gradually increased. Her serum calcium level ranged from 9.0 to 10.0 mg/dL, which caused difficulties in performing vitamin D injection therapy. No parathyroid glands were seen by echography or scintigraphy. On 31 March 2008 her intact PTH (iPTH) level was 895 pg/mL so treatment with cinacalcet 25 mg/day was started. After 3 months her iPTH level decreased to 269 pg/mL and her hemoglobin level increased from 9.3 to 12.9 g/dL. In some cases of severe HPT, anemia improves after parathyroidectomy; however, in this case, cinacalcet improved not only secondary HPT but also anemia.     

Persistent Hypocalcemia with Elevated Parathyroid Hormone Levels After Long-Term Primary Hyperparathyroidism: Report of a Case

We report herein the case of a 48-year-old man with long-term persistent primary hyperparathyroidism (pHPT) despite undergoing a parathyroidectomy in 1976, followed by a reoperation in 1978, for whom resection of a parathyroid adenoma in the upper mediastinum was eventually performed. His postoperative course was complicated by recurrent hypocalcemia refractory to oral calcium substitution and significantly elevated levels of parathyroid hormone (PTH). The radiological findings are presented, and we discuss the possible reasons for the coincidence of severe hypocalcemia with increased PTH levels in association with pHPT. Received: October 18, 1999 / Accepted: May 30, 2000