Determinants of hyperparathyroidism in children after kidney transplantation.

INTRODUCTION: Hyperparathyroidism (HPT) can contribute to metabolic bone disease following kidney transplantation. We evaluated post-transplant trends in intact parathyroid hormone (iPTH) and determined predictors of HPT in pediatric kidney transplant (KTx) recipients. METHODS: In this single-center study, retrospective data were collected on 88 children from 2013 to 2019. Data collected included dialysis vintage, biochemical parameters, post-transplant trends in iPTH, 25(OH)Vitamin D levels and estimated glomerular filtration rate (eGFR ml/min/1.73 m2 ). Pre-transplant treatment for HPT was quantified with a Treatment Burden score (TB, score range: 0-100). After log-transforming skewed variables (iPTH and eGFR), multivariable linear regression was performed to determine predictors of log {iPTH} at 6 and 36 months (mo) post-transplant. RESULTS: Median age was 12.8 (range: 1.9-20.5) years, and dialysis vintage was 11.2 (range: 0.0-112.9) months. The majority were of Hispanic and African Ancestry (77.3%). Median post-transplant iPTH was 69.5 (range: 1.8-306.8) pg/ml at 6 mo with a gradual downward trend to 59.0 (range: 28.0-445.0) pg/ml at 36 mo. Significant multivariable predictors of higher log {iPTH} post-transplant included longer dialysis vintage, higher TB, and lower log{eGFR} at 6 mo, and higher TB, lower log{eGFR}, and deceased donor transplant at 36 mo. CONCLUSIONS: Recognition of risk factors for HPT and monitoring iPTH post-transplant may facilitate timely interventions to mitigate cardiovascular and bone disease in pediatric KTx recipients. KEY MESSAGE: Describe serial trends in intact PTH after kidney transplantation. Pre- and post-transplant factors that contribute to persistence or re-occurrence of hyperparathyroidism after kidney transplantation in children include longer dialysis vintage, high pre-transplant treatment burden and decreased post-transplant GFR. Recognition of these factors, and monitoring intact PTH after kidney transplantation, could facilitate timely interventions to mitigate cardiovascular and bone disease in children.

Impact of hyperparathyroidism on allograft histology and function after kidney transplantation: Rethinking its causal role in graft dysfunction.

INTRODUCTION: The causal relationship between hyperparathyroidism and kidney graft dysfunction remains inconclusive. Applying Bradford-Hill's temporality and consistency causation principles, we assessed the effect of parathyroid hormone (iPTH) on graft histology and eGFR trajectory on kidney transplant recipients (KTRs) with normal time-zero graft biopsies. METHODS: Retrospective cohort study evaluating the effect of hyperparathyroidism on interstitial fibrosis and tubular atrophy (IF/TA) development in 1232 graft biopsies. Pre-transplant hyperparathyroidism was categorized by KDIGO or KDOQI criteria, and post-transplant hyperparathyroidism by iPTH >1× and >2× the URL 1 year after transplantation. RESULTS: We included 325 KTRs (56% female, age 38 ± 13 years, follow-up 4.2 years [IQR: 2.7-5.8]). Based on pre-transplant iPTH levels, 26% and 66% exceeded the KDIGO and KDOQI targets, respectively. There were no significant differences in the development of >25% IF/TA between KTRs with pre-transplant iPTH levels above and within target range according to KDIGO (53% vs. 62%, P = .16, HR.94 [95% CI:.67-1.32]) and KDOQI (60% vs. 60%, P = 1.0, HR 1.19 [95% CI:.88-1.60]) criteria. Similarly, there were no differences when using 1 year post-transplant iPTH cut-offs > 88 pg/mL (58% vs. 64%, P = .33) and > 176 pg/mL (55% vs. 62%, P = .19). After adjusting for confounders, no significant differences were observed in eGFR trajectories among the iPTH strata. CONCLUSION: In young KTRs who received a healthy graft, no association was found between increased pre- and post-transplant iPTH levels and graft dysfunction, as assessed histologically and through eGFR trajectory. The concept of hyperparathyroidism as a risk factor for graft dysfunction in recipients at low risk requires reevaluation.

Pre-Transplant Calcimimetic Use and Dose Information Improves the Accuracy of Prediction of Tertiary Hyperparathyroidism after Kidney Transplantation: A Retrospective Cohort Study.

Tertiary hyperparathyroidism (THPT) is characterized by elevated parathyroid hormone and serum calcium levels after kidney transplantation (KTx). To ascertain whether pre-transplant calcimimetic use and dose information would improve THPT prediction accuracy, this retrospective cohort study evaluated patients who underwent KTx between 2010 and 2022. The primary outcome was the development of clinically relevant THPT. Logistic regression analysis was used to evaluate pre-transplant calcimimetic use as a determinant of THPT development. Participants were categorized into four groups according to calcimimetic dose, developing two THPT prediction models (with or without calcimimetic information). Continuous net reclassification improvement (CNRI) and integrated discrimination improvement (IDI) were calculated to assess ability to reclassify the degree of THPT risk by adding pre-transplant calcimimetic information. Of the 554 patients, 87 (15.7%) developed THPT, whereas 139 (25.1%) received pre-transplant calcimimetic treatment. Multivariate logistic regression analysis revealed that pre-transplant calcimimetic use was significantly associated with THPT development. Pre-transplant calcimimetic information significantly improved the predicted probability accuracy of THPT (CNRI and IDI were 0.91 [p < 0.001], and 0.09 [p < 0.001], respectively). The THPT prediction model including pre-transplant calcimimetic information as a predictive factor can contribute to the prevention and early treatment of THPT in the era of calcimimetics.

A retrospective study of mineral and bone disorder in kidney transplant recipients: Single-center experience.

BACKGROUND: The status of mineral and bone disorder (MBD) after kidney transplantation is not fully understood, and the assessment of abnormal mineral and bone metabolism in kidney transplant recipients (KTRs) has not been standardized. MATERIALS AND METHODS: We performed a retrospective analysis of 292 KTRs in our center. The levels of biochemical markers of bone metabolism and bone mineral density (BMD) were assessed. We evaluated the influencing factors of BMD using linear regression analysis. And correlation test was used for the correlation analysis between bone metabolism indicators and other indicators. RESULTS: Postoperative MBD mainly manifested as hypercalcemia (8.9%), hypophosphatemia (27.1%), low levels of 25-hydroxyvitamin D(25(OH)vitD) (67.0%), hyperparathyroidism (50.6%), and high levels of bone turnover markers (BTMs). The prevalence of osteopenia/osteoporosis in the femoral neck (FN) and lumbar spine (LS) was 20.1%/2.8% and 26.1%/3.6%, respectively. Multivariate analysis indicated that FN BMD was positively associated with body mass index (BMI) and negatively associated with acute rejection history (p < 0.05); while LS BMD was positively associated with BMI, and negatively associated with intact parathyroid hormone (iPTH) (p < 0.05). Biochemical markers of bone metabolism were affected by age, sex, preoperative dialysis mode and time, postoperative time, transplanted kidney function, and iPTH levels. LS BMD was negatively correlated with iPTH and BTMs (p < 0.05). CONCLUSION: MBD persisted after kidney transplantation. Decreased bone mass was associated with persistent hyperparathyroidism, acute rejection history, low BMI, advanced age, and menopause. Dynamic monitoring of bone metabolism index and BMD helps to assess MBD after kidney transplantation.

Outcome of surgical parathyroidectomy for tertiary hyperparathyroidism in kidney transplant recipients: tertiary hyperparathyroidism should not be ignored, for the sake of precious allografts.

Tertiary hyperparathyroidism is a complication of kidney transplantation. This complicated condition carries over from the dialysis period and varies according to the function of the transplanted allograft. Treatments include pharmacotherapy (mainly using calcimimetics) and parathyroidectomy, but calcimimetics are currently not covered by the national insurance system in Japan. Two types of parathyroidectomy can be performed: subtotal parathyroidectomy; and total parathyroidectomy with partial autograft. Both types can be expected to improve hypercalcemia. Concerns about the postoperative deterioration of allograft function are influenced by preoperative allograft function, which is even more likely to be affected by early surgery after kidney transplantation. In general, transient deterioration of allograft function after surgery is not expected to affect graft survival rate in the medium to long term. Tertiary hyperparathyroidism in kidney transplant recipients negatively impacts allograft and patient survival rates, and parathyroidectomy can be expected to improve prognosis in both kidney recipients and dialysis patients. However, studies offering high levels of evidence remain lacking.

Persistent hyperparathyroidism in long-term kidney transplantation: time to consider a less aggressive approach.

PURPOSE OF REVIEW: Persistent hyperparathyroidism affects 50% of long-term kidney transplants with preserved allograft function. Timing, options and the optimal target for treatment remain unclear. Clinical practice guidelines recommend the same therapeutic approach as patients with chronic kidney disease. RECENT FINDINGS: Mild to moderate elevation of parathyroid hormone (PTH) levels in long-term kidney transplants may not be associated with bone loss and fracture. Recent findings on bone biopsy revealed the lack of association between hypercalcaemic hyperparathyroidism with pathology of high bone turnover. Elevated PTH levels may be required to maintain normal bone volume. Nevertheless, several large observational studies have revealed the association between hypercalcemia and the elevation of PTH levels with unfavourable allograft and patient outcomes. Both calcimimetics and parathyroidectomy are effective in lowering serum calcium and PTH. A recent meta-analysis suggested parathyroidectomy may be performed safely after kidney transplantation without deterioration of allograft function. SUMMARY: Treatment of persistent hyperparathyroidism is warranted in kidney transplants with hypercalcemia and markedly elevated PTH levels. A less aggressive approach should be applied to those with mild to moderate elevation. Whether treatments improve outcomes remain to be elucidated.

Missed Opportunities to Diagnose and Treat Tertiary Hyperparathyroidism After Transplant.

INTRODUCTION: Tertiary hyperparathyroidism (3HPT) is common after renal transplant. However, guidelines for diagnosis are not clear and few patients are treated surgically. This study aims to determine rates of diagnosis and treatment of 3HPT in renal transplant patients with hypercalcemia. MATERIALS AND METHODS: This retrospective chart review identified all renal transplant recipients at a single tertiary care institution between 2011 and 2021. Patients with post-transplant hypercalcemia (> 10.2 mg/dL) were identified. The time in months of index hypercalcemia was noted. Measurement of parathyroid hormone (PTH) levels after index hypercalcemia was determined and noted as elevated if > 64 pg/mL at least 6 mo after transplant. Documentation of symptoms of hyperparathyroidism, a diagnosis of hyperparathyroidism in the electronic medical record, and medical or surgical management of patients with classic 3HPT (elevated calcium and PTH) were determined. RESULTS: Of 383 renal transplant recipients, hypercalcemia was identified in 132 patients. The majority of hypercalcemic patients had PTH levels measured (127, 96.2%). PTH was elevated in 109 (82.6%). Among the 109 patients with classic 3HPT, 54 (49.5%) had a documented diagnosis of hyperparathyroidism in the electronic medical record (P = 0.01). Kidney stones or abnormal DEXA scan were present in 16 (14.7%) and 18 (16.5%), respectively. Most patients were managed non-surgically (101, 92.6%); calcimimetics were prescribed for 42 (38.5%, P = 0.01). Eight (7.3%) patients with classic 3HPT were referred to a surgeon (P = 0.35); all were initially prescribed calcimimetics (P = 0.001). CONCLUSIONS: 3HPT is underdiagnosed in patients with elevated calcium and PTH levels post-transplant. A significant percentage of these patients go without surgical referral and curative treatment.

Persistent hyperparathyroidism after preemptive kidney transplantation.

BACKGROUND: Long-term dialysis vintage is a predictor of persistent hyperparathyroidism (HPT) after kidney transplantation (KTx). Recently, preemptive kidney transplantation (PKT) has increased. However, the incidence, predictors, and clinical implications of HPT after PKT are unclear. Here, we aimed to elucidate these considerations. METHODS: In this retrospective cohort study, we enrolled patients who underwent PKT between 2000 and 2016. Those who lost their graft within 1 year posttransplant were excluded. HPT was defined as an intact parathyroid hormone (PTH) level exceeding 80 pg/mL or hypercalcemia unexplained by causes other than HPT. Patients were divided into two groups based on the presence of HPT 1 year after PKT. The primary outcome was the predictors of HPT after PKT, and the secondary outcome was graft survival. RESULTS: Among the 340 consecutive patients who underwent PKT, 188 did not have HPT (HPT-free group) and 152 had HPT (HPT group). Multivariate logistic regression analysis revealed that pretransplant PTH level (P < 0.001; odds ratio [OR], 5.480; 95% confidence interval [CI], 2.070-14.50) and preoperative donor-estimated glomerular filtration rate (P = 0.033; OR, 0.978; 95% CI, 0.957-0.998) were independent predictors of HPT after PKT. Death-censored graft survival was significantly lower in the HPT group than that in the HPT-free group (90.4% vs. 96.4% at 10 years, P = 0.009). CONCLUSIONS: Pretransplant PTH levels and donor kidney function were independent predictors of HPT after PKT. In addition, HPT was associated with worse graft outcomes even after PKT.

Impact of Pre-Transplant Parathyroidectomy on Graft Survival: A Comparative Study of Renal Transplant Patients (2005-2015).

BACKGROUND Hyperparathyroidism poses significant risks for patients prior to kidney transplantation. However, the outcomes of patients who undergo parathyroidectomy before renal transplantation compared to those without such a procedure remain uncertain. This real-world data study aimed to examine the clinical outcomes of both patient groups. MATERIAL AND METHODS Using the Taiwan National Health Insurance Research Database, we conducted a retrospective cohort study on patients who underwent renal transplantation between January 2005 and December 2015. The patients were divided into two groups: a case group (n=294) with parathyroidectomy and a control group (n=588) without the need for parathyroidectomy before kidney transplantation. The groups were matched based on age, sex, dialysis vintage, and baseline characteristics at a 1:2 ratio. Hazard ratios (HR) were estimated using the Cox regression model. The main outcomes assessed were graft failure, mortality, and major adverse cardiovascular events (MACE) recorded until December 2019. RESULTS During a mean follow-up period of 6 years, a significant difference was observed in graft failure (HR 1.40; 95% confidence interval 1.10-1.79, p=0.007) between the two groups. After further adjustment, graft failure remained significant (HR 1.52; 95% CI 1.07-2.15, p=0.019). Additionally, machine learning-based feature selection identified the importance of parathyroidectomy (ranked 9 out of 11) before kidney transplantation in predicting subsequent graft failure. CONCLUSIONS Our study demonstrates that severe hyperparathyroidism requiring parathyroidectomy before kidney transplantation may contribute to poor post-transplant graft outcomes compared to patients who do not require parathyroidectomy.

Parathyroidectomy for Normocalcemic Tertiary Hyperparathyroidism: A 19-Year Experience.

INTRODUCTION: Parathyroidectomy is the standard management for patients with tertiary hyperparathyroidism (THPT) and hypercalcemia. However, a subset of patients with THPT have normal or mildly-elevated serum calcium levels in the setting of significantly elevated parathyroid hormone (PTH). The purpose of this study is to determine the effectiveness and safety of parathyroidectomy in normocalcemic THPT. MATERIALS AND METHODS: Retrospective review of 212 consecutive patients with THPT who subsequently underwent parathyroidectomy between 2001 and 2020 was performed. Patients were categorized as normocalcemic, "mild" (Ca ≤ 10.4 mg/dL) or hypercalcemic, "classic" THPT (Ca ≥ 10.5 mg/dL) and clinical data are compared. RESULTS: 71 of 212 (34%) were normocalcemic with median pre-operative Ca and PTH levels of 9.7 mg/dL and 225pg/mL, respectively and 141 of 212 (67%) were hypercalcemic with median preoperative Ca and PTH levels of 11 mg/dL and 211pg/mL, respectively. The mean length of stay was shorter in normocalcemic patients (0.33 versus 0.50 d; P = 0.03). 10 of 71 (14%) normocalcemic patients underwent reoperative parathyroidectomy, more than double that of hypercalcemic patients (5.6%; P = 0.06). Concomitant thymectomy was performed in 28.1% and 22.1% of normocalcemia and hypercalcemic patients, respectively (P = 0.44). No patient in either group required intravenous calcium or had undetectable PTH levels, but permanent hypocalcemia was more frequent in normocalcemic compared to hypercalcemic patients (11.2% versus 1.4%; P = 0.03). CONCLUSIONS: Parathyroidectomy for normocalcemic tertiary hyperthyroidism (HPT) can be performed safely. These data can help guide multidisciplinary discussions for earlier surgical referral and intervention. Future investigations are needed to evaluate the impact of parathyroidectomy on the renal allograft, bone health, and cardiovascular disease.

Surgery Is Underutilized in the Management of Tertiary Hyperparathyroidism.

INTRODUCTION: Tertiary hyperparathyroidism (3HPT) is observed in up to 40% of renal transplant patients. Standard guidelines defining 3HPT and indications for operative intervention are not well described. METHODS: We conducted a retrospective, single-institution cohort study of patients who underwent renal transplant between January 1, 2012 and January 30, 2018, with a minimum of 13-month follow-up and at least 1 y of allograft function. We defined 3HPT as having elevated serum level parathyroid hormone (>88 pg/mL) after successful renal transplantation or multiple instances of elevated serum calcium starting at least 3 mo after transplant. We compared graft failure rates after stratifying the cohort based on management strategy: expectant, medical management with cinacalcet, and parathyroidectomy. RESULTS: Out of the 381 transplanted patients with functional grafts at 1 y, 178 patients (46.6%) were found to have 3HPT. One hundred twenty-nine patients (72.5%) were managed expectantly without medications, 35 patients (19.7%) were managed medically, and 14 patients (7.8%) were managed with parathyroidectomy. Twenty-two patients (17.1%) in the observation group had graft failure, 4 patients (11.4%) in the medically managed group had graft failure, and 0 patients in the surgery group had graft failure. Surgical intervention was associated with decreased renal allograft failure when compared to the combined cohort of nonoperative 3HPT patients (P = 0.03). All patients who underwent parathyroidectomy were cured and did not have graft failure as of December 30, 2019. Calcium elevation, but not PTH elevation, was associated with referral for parathyroidectomy on multivariable logistic regression analysis (P < 0.01). CONCLUSIONS: At our institution, the referral rate for parathyroidectomy among patients with 3HPT remains low. Parathyroidectomy was associated with high cure rates and reduced graft failure. Surgery may be underutilized in the management of 3HPT.

Impact of parathyroidectomy on kidney graft function in post-transplant tertiary hyperparathyroidism: a comparative study.

PURPOSE: Parathyroidectomy to treat tertiary hyperparathyroidism (THPT) is now on a par with calcimimetic treatment. The effects of cinacalcet and parathyroidectomy on kidney transplant function remain controversial. The aim of this study was to evaluate kidney transplant function in THPT patients treated either by parathyroidectomy, cinacalcet, or not treated. METHODS: Between 2009 and 2019, 231 patients with functional grafts presenting THPT, defined either by calcaemia superior to 2.5 mmol/L with elevated PTH level or hypercalcaemia with non-adapted PTH level 1 year after kidney transplantation, were included. Hyperparathyroid patients treated by cinacalcet and parathyroidectomy were matched for age, sex, graft rank, and baseline eGFR with cinacalcet-only and untreated patients. Conditional logistic regression models were used to compare eGFR variations 1 year after parathyroidectomy between operated patients and matched controls. Five-year survivals were compared with the Mantel-Cox test. RESULTS: Eleven patients treated with parathyroidectomy and cinacalcet were matched with 16 patients treated by cinacalcet-only and 29 untreated patients. Demographic characteristics were comparable between groups. Estimated odds ratios for eGFR evolution in operated patients compared with cinacalcet-only and untreated patients were 0.92 [95%CI 0.83-1.02] and 0.99 [0.89-1.10] respectively, indicating no significant impairment of eGFR 1 year after surgery. Five-year allograft survival was not significantly impaired in operated patients. CONCLUSIONS: Parathyroidectomy did not appear to substantially alter or improve graft function 1 year after surgery or 5-year allograft survival. It could be hypothesized that in addition to its known benefits, parathyroidectomy can be safely performed vis-à-vis graft function in tertiary hyperparathyroidism.

Parathyroidectomy for Tertiary Hyperparathyroidism: A Multi-Institutional Analysis of Outcomes.

BACKGROUND: Patients with tertiary hyperparathyroidism (HPT) often experience delays between diagnosis and referral for surgical treatment. We hypothesized that patients with tertiary HPT experience similarly high cure rates and low complication rates after parathyroidectomy compared with patients with primary HPT. METHODS: We retrospectively identified patients undergoing parathyroidectomy from the Collaborative Endocrine Surgery Quality Improvement Program for primary or tertiary HPT from January 2014 to April 2019. Patients were categorized according to their primary diagnosis and compared for cure rates and surgical complications. RESULTS: The study included 9030 patients, with 334 (3.7%) being treated for tertiary HPT. Parathyroidectomy provided a high cure rate (93.7%) in patients with tertiary HPT. However, adjusting for age, sex, and prior thyroid or parathyroid surgery, tertiary HPT was associated with a greater chance of persistent disease than was primary HPT (odds ratio: 2.3, 95% confidence interval: 1.3-4.0). Overall, complications were low for patients across both groups. However, patients with tertiary HPT were more likely to present to the emergency department (7.5% versus 3.3%; P < 0.001), be readmitted (5.1% versus 1.1%; P < 0.001), and develop a hematoma (1.5% versus 0.2%; P = 0.002). Both groups of patients shared similarly low rates of other complications, including mortality, vocal cord dysfunction, and surgical site infections (P < 0.5% for all). CONCLUSIONS: Patients undergoing parathyroidectomy for tertiary HPT experience high cure rates and low complication rates. However, tertiary HPT is associated with a greater chance of persistent disease and select complications. Nevertheless, the low rates of persistent disease and complications should not deter early referral for the treatment of tertiary HPT.

Body mass index is associated with hyperparathyroidism in pediatric kidney transplant recipients.

BACKGROUND: Hyperparathyroidism persists in up to 50% of pediatric kidney transplant recipients. The aims of this study were to describe the evolution of parathyroid hormone (PTH) in the first year after transplantation and to identify factors associated with hyperparathyroidism. METHODS: This retrospective study included children who underwent kidney transplantation at the University Hospitals of Ghent, Leuven, Rotterdam, or Amsterdam. Data from 149 patients were collected before and up to 12 months after transplantation. Severe hyperparathyroidism was defined as PTH 2-fold above the reference value. Factors associated with hyperparathyroidism and severe hyperparathyroidism were identified using multivariate logistic regression analysis. RESULTS: Before transplantation, 97 out of 137 patients (71%) had hyperparathyroidism. The probability of hyperparathyroidism and severe hyperparathyroidism declined from 0.49 and 0.17 to 0.29 and 0.09 at 3 and 12 months after transplantation, respectively. BMI SDS (ß: 0.509; p = 0.011; 95% CI: 1.122-2.468), eGFR (ß: - 0.227; p = 0.030; 95% CI: 0.649-0.978), and pre-transplant hyperparathyroidism (ß: 1.149; p = 0.039; 95% CI: 1.062-9.369) were associated with hyperparathyroidism 12 months after transplantation. Pre-transplant hyperparathyroidism (ß: 2.115; p = 0.044; 95% CI: 1.055-65.084), defined as intact parathormone (iPTH) levels > 65 ng/l (6.9 pmol/l) or 1-84 PTH > 58 ng/l (6.2 pmol/l), was associated with severe hyperparathyroidism at 3 months. Only eGFR (ß: - 0.488; p = 0.010; 95% CI: 0.425-0.888) was inversely associated with severe hyperparathyroidism at 9 months after transplantation. CONCLUSIONS: Allograft function remains the main determinant of severe hyperparathyroidism after transplantation. Our findings emphasize the importance of BMI and pre-transplant PTH control.

Preoperative Imaging in Renal Transplant Patients with Tertiary Hyperparathyroidism.

BACKGROUND: Tertiary hyperparathyroidism following kidney transplantation is most commonly characterized by 4-gland hyperplasia, but single and double adenomatous disease has been demonstrated in this population as well. It is unknown whether preoperative imaging can assist in identifying patients who may qualify for focused surgery for adenomatous disease. MATERIALS AND METHODS: We performed a retrospective review of our patient database from 1998-2018 for patients with tertiary hyperparathyroidism following renal transplant. Patient charts were reviewed for patient demographics, laboratory values, preoperative imaging, operative findings, pathology, and complications. RESULTS: We identified 113 patients with tertiary hyperparathyroidism following renal transplant who underwent parathyroidectomy. There were 51 females and 62 males with a mean age of 53.4 ± 13.4 years. Median preoperative calcium and PTH were 10.9 mg/dl (IQR 10.3-11.2) and 228 pg/ml (IQR 118-305). Preoperative ultrasound was performed in 60 patients. Of these, 11 (18%) were negative, 38 (63%) showed 1-2 adenomas, and 11 (18%) showed ≥ 3 adenomas. 99mTc-sestamibi parathyroid scintigraphy was performed in 101/113 patients. Of these, 11 (11%) were negative, 62 (61%) showed 1-2 areas of discordant sestamibi uptake, and 28 (28%) showed ≥ 3 areas of discordant uptake. Ultimately, 19 (17%) patients had a single adenoma removed, 16 (14%) had 2 adenomas removed, and (69%) had multi-gland disease. There were 26 ectopic glands found in 21 patients, 42.3% of which were identified on preoperative imaging. 94.1% of patients were eucalcemic at last follow-up, mean (± SD) 5.8 ± 3.6 years. Adenomas that were visualized on ultrasound were larger on pathology than those non-visualized (997 ± 120 mg (mean ± SE) vs. 388 ± 109 mg, p = 0.0003). This was also true for parathyroid scintigraphy (647 ± 41 mg vs. 355 ± 51 mg, p = 0.0001). CONCLUSION: In patients with tertiary hyperparathyroidism, preoperative imaging can aid in predicting which patients will have 1-2 gland disease. In patients with 1-2 gland disease on congruent ultrasound and nuclear medicine imaging studies, the accuracy increases to 59%. Preoperative imaging can help identify ectopic glands. Larger adenomas are more likely to be identified on both imaging modalities.

Three-Year Outcomes of Bariatric Surgery in Patients With Obesity and Hypertension : A Randomized Clinical Trial.

BACKGROUND: Midterm effects of bariatric surgery on patients with obesity and hypertension remain uncertain. OBJECTIVE: To determine the 3-year effects of Roux-en-Y gastric bypass (RYGB) on blood pressure (BP) compared with medical therapy (MT) alone. DESIGN: Randomized clinical trial. (ClinicalTrials.gov: NCT01784848). SETTING: Investigator-initiated study at Heart Hospital (HCor), São Paulo, Brazil. PARTICIPANTS: Patients with hypertension receiving at least 2 medications at maximum doses or more than 2 medications at moderate doses and with a body mass index (BMI) between 30.0 and 39.9 kg/m2 were randomly assigned (1:1 ratio). INTERVENTION: RYGB plus MT or MT alone. MEASUREMENTS: The primary outcome was at least a 30% reduction in total number of antihypertensive medications while maintaining BP less than 140/90 mm Hg. Key secondary outcomes were number of antihypertensive medications, hypertension remission, and BP control according to current guidelines (<130/80 mm Hg). RESULTS: Among 100 patients (76% female; mean BMI, 36.9 kg/m2 [SD, 2.7]), 88% from the RYGB group and 80% from the MT group completed follow-up. At 3 years, the primary outcome occurred in 73% of patients from the RYGB group compared with 11% of patients from the MT group (relative risk, 6.52 [95% CI, 2.50 to 17.03]; P < 0.001). Of the randomly assigned participants, 35% and 31% from the RYGB group and 2% and 0% from the MT group achieved BP less than 140/90 mm Hg and less than 130/80 mm Hg without medications, respectively. Median (interquartile range) number of medications in the RYGB and MT groups at 3 years was 1 (0 to 2) and 3 (2.8 to 4), respectively (P < 0.001). Total weight loss was 27.8% and -0.1% in the RYGB and MT groups, respectively. In the RYGB group, 13 patients developed hypovitaminosis B12 and 2 patients required reoperation. LIMITATION: Single-center, nonblinded trial. CONCLUSION: RYGB is an effective strategy for midterm BP control and hypertension remission, with fewer medications required in patients with hypertension and obesity. PRIMARY FUNDING SOURCE: Ethicon, represented in Brazil by Johnson & Johnson do Brasil.

Early persistent hyperparathyroidism post-renal transplantation as a predictor of worse graft function and mortality after transplantation.

BACKGROUND: Persistent hyperparathyroidism (pHPT) is frequently seen after transplantation contributing to post-transplant complications. METHODS: We conducted a retrospective single center analysis to explore the relationship of early pHPT and long-term allograft outcome. Patients were divided into high (N = 153) and low (N = 252) PTH groups based on serum parathyroid hormone (PTH) level 3 months post-transplant (PTH ≥ 150 and < 150 pg/mL, respectively). RESULTS: High PTH was found to be an independent predictor for reduced kidney allograft function up to 3 years post-transplant. eGFR decreased by 11.4 mL/min (P < .001) and the odds of having an eGFR < 60 mL/min 3 years post-transplant were sixfold higher (P < .01) in the high compared to the low PTH group. Subgroup analysis based on eGFR 1 year post-transplant, presence of slow graft function (SGF), and transplant type revealed similar results. High PTH three months post-transplant was also independently associated with an increased risk for overall mortality and for death with a functioning graft (P < .05). CONCLUSIONS: pHPT three months post-renal transplantation is an independent predictor for a worse allograft function up to 3 years post-transplant and a risk factor for mortality. This relationship remains statistically significant after accounting for baseline allograft function, presence of SGF and serum mineral levels abnormalities.

Endoscopic parathyroidectomy using a three-port submental approach.

PURPOSE: The three-port submental endoscopic approach and its variations were introduced in 2016 and have been used for thyroidectomy since. However, there has been no report of this approach being used for parathyroidectomy [1, 2]. The objective of this paper was thus to report our experience using a three-port submental approach for endoscopic parathyroidectomy in challenging cases such as tertiary parathyroidism. METHODS: We compared the outcomes before and after endoscopic removal of the parathyroid glands using a three-port submental endoscopic approach. RESULTS: Endoscopic subtotal parathyroidectomy was performed using submental approach in five patients with tertiary hyperparathyroidism from January 2018 to June 2019. The parathyroid hormone levels of the patients dropped significantly after undergoing subtotal parathyroidectomy (mean difference 2260 pg/ml; 95% CI 1883.74 to 2636.65), as did calcium levels (mean difference 2.84 mg/dl; 95% CI 1.90 to 3.78). No major adverse events occurred in this study. CONCLUSIONS: Submental approach parathyroidectomy allows for visualization of all parathyroid glands. Surgical scarring was minor and was hidden under the chin. The surgical outcomes were promising, and there were no major complications.

Ultrasound dye-assisted parathyroidectomy (USDAP): Experience of a tertiary center.

BACKGROUND: Primary hyperparathyroidism is primarily caused by parathyroid adenoma, followed by hyperplasia and parathyroid carcinoma. In the era of minimally invasive, targeted parathyroidectomy, the main challenge remains that of distinguishing intraoperatively pathological parathyroid from normal glands and peri-thyroid fat tissue. The aim of this study is to evaluate the surgical outcomes of a novel minimally invasive technique called ultrasound-guided dye-assisted parathyroidectomy (USDAP). METHODS: We perform a retrospective analysis of patients affected by parathyroid adenoma, treated with USDAP at our institution between 2014 and 2019. Data were collected on patient age and sex, tumor location and size, preoperative investigations, histopathology, perioperative complications and surgical outcomes. RESULTS: Between January 2014 and June 2019, 43 patients underwent parathyroidectomy in our Institute. Each case was discussed by the Institutional Multidisciplinary Board. All patients undergoing thyroidectomy together with USDAP or patients undergoing USDAP under endoscopic control were excluded from the present study. The final cohort, the largest to our knowledge, consisted of 29 patients. All patients were successfully treated with USDAP and remained disease-free during follow up. In all cases, pathological parathyroid was correctly identified and removed. There was no postoperative allergic reaction, nor were there neurotoxicity complications. USDAP permitted a shortening of operative and hospitalization time. CONCLUSIONS: USDAP is an effective and safe procedure both as first line treatment and as a re-operative procedure after previous surgical failures in selected cases.

Intraoperative Parathyroid Hormone Monitoring in Parathyroidectomy for Tertiary Hyperparathyroidism.

BACKGROUND: Tertiary hyperparathyroidism (THPT) is characterized by hypercalcemia and hyperparathyroidism after renal allograft. Limited data exist regarding the use of intraoperative parathyroid hormone (IOPTH) for THPT. We examined our series of parathyroidectomies performed for THPT to determine clinical outcomes with respect to IOPTH. MATERIALS AND METHODS: Patients who underwent parathyroidectomy for THPT (1999-2017) were identified for inclusion. Retrospective chart review was performed. Cure was defined as eucalcemia ≥6 mo after surgery. Statistical analysis was performed. RESULTS: Of 41 patients included in the study, 41% (n = 17) were female. The median duration of dialysis before renal allograft was 34 mo (interquartile interval [IQI]:6-60). Preoperatively, the median calcium level was 10.4 mg/dL (IQI:10.0-11.2), median parathyroid hormone was 172 pg/mL (IQI:104-293), and renal function was minimally abnormal with median glomerular filtration rate 58 mL/min/1.73 m2 (IQI:49-71). At surgery, the median final IOPTH was 40 pg/mL (IQI:29-73), and median decrease in IOPTH was 78% (IQI:72-87), with 88% (n = 36) of patients demonstrating >50% decrease. Median calcium level ≥6 mo after surgery was 9.4 mg/dL (IQI:8.8-9.7), and only one patient had recurrent hypercalcemia. Failure to achieve >50% decrease in IOPTH was not significantly associated with recurrent hypercalcemia (P = 1.000). With a median follow-up time of 41 mo (IQI:25-70), only three patients had graft failure. The positive predictive value of IOPTH for cure was 89% (95% confidence interval: 0.752-0.971), with 0% negative predictive value and 87% accuracy (95% confidence interval: 0.726-0.957). CONCLUSIONS: Subtotal parathyroidectomy is a successful operation with durable cure of THPT. IOPTH fails to predict long-term cure in THPT despite minimally abnormal renal function.