Pre-Operative Localization of Parathyroid Adenoma: Performance of 4D Mri Parathyroid Protocol

Objective: Accurate pre-operative image localization is critical in the selection of minimally invasive parathyroidectomy as a surgical treatment approach in patients with primary hyperparathyroidism (PHPT). Sestamibi scan, ultrasound, computed tomography, and conventional magnetic resonance imaging (MRI) has varying accuracy in localizing parathyroid adenoma (PTA). Our group has previously shown that four-dimensional (4D) MRI is more accurate than conventional imaging in identifying single adenomas. In this study, we set out to determine if it is possible to accurately localize the quadrant of the adenoma using 4D MRI.Methods: We analyzed and matched the quadrants of PTA identified by pre-operative 4D-MRI with the operative findings during parathyroidectomy for PHPT at our institution during the study period. All resections were confirmed to be successful with an adequate decrease in intraoperative parathyroid hormone as defined by the Miami criterion.Results: A total of 26 patients with PHPT underwent pre-operative localization with the 4D MRI parathyroid protocol. Fourteen patients had true single-gland adenoma (SGA) and 12 patients had multi-gland disease (MGD). 4D MRI accurately identified all the SGA. Using this method, we were also able to localize the adenoma in the correct quadrant in 14 of the 18 patients with SGA. All 3 double adenomas were accurately identified using 4D MRI; however, MGD was only accurately identified 67% of the time. The 4D MRI had an overall 85% accuracy in distinguishing SGA from MGD.Conclusion: 4D MRI accurately identified single and double adenomas in their respective quadrants. However, accuracy was lower with MGD.Abbreviations: BNE = bilateral neck exploration; CT = computed tomography; IOPTH = intra-operative parathyroid hormone; MGD = multi-gland disease; MIBI = sestamibi; MIP = minimally invasive parathyroidectomy; MRI = magnetic resonance imaging; PHPT = primary hyperparathyroidism; PTA = parathyroid adenoma; PTH = parathyroid hormone; SGA = single-gland adenoma; SPECT = single photon emission computed tomography; 4D = four-dimensional     

Identifying Parathyroid Hormone Disorders and their Phenotypes through a Bone Health Screening Panel: It's not Simple Vitamin D Deficiency!

Objectives: To determine the utility of bone health screening panels in identifying disorders of parathyroid gland secretions.Methods: A retrospective analysis of biochemical parameters in a bone health screening panel (BHSP) was conducted. Low and high cutoffs were applied to determine hypofunctioning and hyperfunctioning conditions related to parathyroid hormone. Clinical phenotypes of parathyroid gland abnormalities were determined using a combination of levels of calcium, 25-hydroxyvitamin D, and intact parathyroid hormone (iPTH). A PTH nomogram was applied to calculate the maximum expected PTH for existing levels of 25-hydroxyvitamin D. Medical records of patients were reviewed for clinical validation of biochemical findings.Results: Sixty-eight percent of subjects showed abnormal PTH secretion. Primary hyper- and hypoparathyroidism were detected in 1% (n = 5) and 0.4% (n = 2) of subjects, respectively. Normocalcemic hyperparathyroidism and hypercalcemia with inappropriately high-normal PTH were identified in 8.5% (n = 37) and 2% (n = 10) of subjects, respectively. All subjects with primary and normocalcemic hyperparathyroidism had higher measured PTH than calculated maximum PTH using the PTH nomogram. Secondary hyperparathyroidism and functional hypoparathyroidism were present in 18% (n = 88) and 39% (n = 194) of subjects, respectively. High prevalence of bone pains, renal stones, and low bone mineral density were identified in patients with abnormal PTH secretion.Conclusion: Panel testing is useful in early diagnosis of metabolic bone disorders related to PTH. A BHSP helps identify normocalcemic hyperparathyroidism and hypercalcemia with inappropriately high PTH.Abbreviations:25OHD = 25-hydroxyvitamin DAKUH = Aga Khan University HospitalBHSP = bone health screening paneliPTH = intact parathyroid hormonemaxPTH = maximum parathyroid hormoneMBD = metabolic bone diseaseNCHPT = normocalcemic hyperparathyroidismPHPT = primary hyperparathyroidismPTH = parathyroid hormoneSHPT = secondary hyperparathyroidismVDD = vitamin D deficiency     

Increased Serum Calcitonin in Sporadic Primary Hyperparathyroidism is an Uncommon Occurrence

Objective: To evaluate calcitonin (CT) levels in sporadic primary hyperparathyroidism (PHPT), which has to date rarely been considered.Methods: We evaluated serum CT levels in 290 consecutive patients with sporadic PHPT at diagnosis.Results: Mild elevations in CT levels (hyperCT) were found in 25 patients (8.6%), with no correlation among the demographic, clinical, and biochemical findings. In addition, no differences were found between patients with and without hyperCT. Follow-up data were available for 19/25 patients, but CT values were only available for 10. CT normalized in all surgically cured patients regardless of the extent of the surgery (parathyroidectomy [PTX] only in 8 and associated with partial or total thyroidectomy for benign nodular goiters in 7).Conclusion: hyperCT is an uncommon feature of sporadic PHPT and not related to biochemical or clinical features of the disease. In addition, hyperCT is reversible after PTX, regardless of whether concomitant thyroidectomies have been conducted.Abbreviations: CT = calcitonin; eGFR = estimated glomerular filtration rate; hyperCT = hypercalcitoninemia; MEN = multiple endocrine neoplasm; MTC = medullary thyroid carcinoma; PHPT = primary hyperparathyroidism; PPI = proton pump inhibitor; PTH = parathyroid hormone; PTX = parathyroidectomy     

Significance of Elevated Parathyroid Hormone After Parathyroidectomy

ObjectiveTo review the prevalence of parathyroid hormone elevation after parathyroidectomy for primary hyperparathyroidism and to discuss possible mechanisms.MethodsA Medline search of the English-language literature published between 1990 and 2009 was performed using the search terms “elevated PTH after parathyroidectomy.” All of the identified articles reported either prospective or retrospective studies without control groups. Studies that included patients with secondary or tertiary hyperparathyroidism were not reviewed.ResultsWithin 1 week to 5 years after parathyroidectomy, 9% to 62% of patients with a normal serum calcium concentration are reported to have an elevated parathyroid hormone concentration. No evidence suggests that postoperative normocalcemic parathyroid hormone elevation is an indication of surgical failure and recurrent hypercalcemia. Preoperative findings in patients with postoperative parathyroid hormone elevation include lower vitamin D concentration, higher concentrations of bone turnover markers, and higher parathyroid hormone concentration. Potential mechanisms for parathyroid hormone elevation in the setting of normocalcemia include vitamin D deficiency, hungry bone syndrome, and parathyroid hormone resistance. Study findings suggest a possible benefit of postoperative calcium and vitamin D supplementation, but no randomized trials have been done.ConclusionElevation of parathyroid hormone commonly occurs after parathyroidectomy for primary hyperparathyroidism, although the underlying mechanism remains unclear. (Endocr Pract. 2010;16:112-117)     

Biochemical Dynamics of Untreated Primary Hyperparathyroidism: an Observational Study

Objective: The natural biochemical history of untreated primary hyperparathyroidism (PHPT) is poorly understood. The purpose of this study was to determine the extent of biochemical fluctuations in patients with PHPT.Methods: Retrospective cohort study from January 1, 1995, to December 31, 2014. Serum calcium and parathyroid hormone (PTH) levels in patients with classic (Ca >10.5 mg/dL, PTH >65 pg/mL) and nonclassic (Ca >10.5 mg/dL, PTH 40 to 65 pg/mL) PHPT were followed longitudinally at 1, 2, and 5 years. Biochemical profiles in follow-up were ranked in descending biochemical severity as classic PHPT, nonclassic PHPT, normal calcium with elevated PTH (Ca <10.5 mg/dL, PTH >65 pg/mL), possible PHPT (Ca >10.5 mg/dL, PTH 21 to 40 pg/mL), or absent PHPT (Ca >10.5 mg/dL, PTH <21 pg/mL or Ca <10.5 mg/dL, PTH <65 pg/mL).Results: Of 10,598 patients, 1,570 were treated with parathyroidectomy (n = 1,433) or medications (n = 137), and 4,367 were censored due to study closure, disenrollment, or death. In the remaining 4,661 untreated patients with 5 years of follow-up, 235 (5.0%) progressed to a state of increased biochemical severity, whereas 972 (20.8%) remained the same, and 3,454 (74.1%) regressed to milder biochemical states. In 2,522 untreated patients with classic PHPT, patients most frequently transitioned to the normal calcium with elevated PTH group (n = 1,257, 49.8%). In 2,139 untreated patients with nonclassic PHPT, patients most frequently transitioned to the absent PHPT group (n = 1,354, 63.3%).Conclusion: PHPT is a biochemically dynamic disease with significant numbers of patients exhibiting both increases and decreases in biochemical severity.Abbreviations: IQR = interquartile range; KPSC = Kaiser Permanente Southern California; PHPT = primary hyperparathyroidism; PTH = parathyroid hormone; PTx = parathyroidectomy     

HRPT2- (CDC73) Related Hereditary Hyperparathyroidism: A Case Series From Western India

Objective: To describe a case series of HRPT2- (CDC73) related hereditary primary hyperparathyroidism (PHPT) from western India.Methods: We present a case series of 4 families (7 patients) with PHPT caused by CDC73 gene mutations.Results: The mean age of presentation of the 4 index cases was 27.25 ± 9.8 years. Two family members were identified through biochemical screening (Cases 1b and 2b), while 1 mutation-positive family member did not manifest any features of PHPT or hyperparathyroidism jaw tumor syndrome (HPT-JT) syndrome (Case 2c). Biochemistry showed increased serum calcium (mean: 13.21 ± 1.24 mg/dL), low serum phosphorus (mean: 1.78 ± 0.44 mg/dL), and high parathyroid hormone (PTH, mean: 936 ± 586.9 pg/mL).All patients had a uniglandular presentation and underwent single adenoma excision initially except Cases 2a and 2b, who underwent subtotal parathyroidectomy at baseline. Two cases experienced PHPT recurrence (Cases 3 and 4), while 1 remained uncured due to parathyroid carcinoma (Case 1a). Other associated syndromic features like ossifying jaw fibromas were present in 2 patients, renal cysts in 3 patients, and uterine involvement in 2 patients. Two families had novel germline CDC73 mutations (Families 1 and 3), while the other 2 had reported mutations. Family 2 had familial isolated PHPT without any other features of HPT-JT syndrome.Conclusion: Our findings reaffirm the need for genetic analysis of patients with PHPT, especially those with younger age of disease onset; recurrent disease; and associated features like polycystic kidneys, endometrial involvement, ossifying jaw tumors, or parathyroid carcinoma.Abbreviations: FIHP = familial isolated hyperparathyroidism HPT-JT = hyperparathyroidism jaw tumor syndrome PHPT = primary hyperparathyroidism PTH = parathyroid hormone ⁹⁹Tc = ⁹⁹Technetium     

Unknown and Already Known Thyroid Abnormalities in Primary Hyperparathyroidism

Objective: Primary hyperparathyroidism (PHPT) and thyroid diseases are highly prevalent in the general population, but the putative link between the 2 conditions remains unclear.Methods: A monocentric consecutive series of 434 patients with PHPT was retrospectively evaluated by lab and ultrasonography to look for thyroid abnormalities. Patients were classified in 3 groups: without thyroid abnormalities (group 1, n = 171), with thyroid diseases not previously known (group 2a, n = 69), and thyroid diseases previously known (group 2b, n = 194).Results: In terms of thyroid disease, no significant difference was found between groups 2a and 2b, except for the significantly larger number of patients with toxic nodular goiter in group 2b. PHPT was more frequently symptomatic in group 2a than in group 2b, despite no differences in serum calcium, creatinine, parathyroid hormone (PTH), or 25-hydroxyvitamin D (25OHD) levels.Conclusion: A total of 60% of PHPT patients had a thyroid disease that was unknown prior to PHPT diagnosis in almost one-third of cases. The newly diagnosed and previously known thyroid diseases were similar, both mostly affecting postmenopausal females.Abbreviations: Ab = antibody; aPHPT = asymptomatic PHPT; 25OHD = 25-hydroxyvitamin D; PHPT = primary hyperparathyroidism; PTH = parathyroid hormone; Tg = thyroglobulin; TPO = thyroperoxidase; TSH = thyroid-stimulating hormone; US = ultrasound     

Receiver Operating Characteristic Analysis of Intraoperative Parathyroid Hormone Monitoring to Determine Optimum Sensitivity and Specificity: Analysis of 896 Cases

Objective: While intraoperative parathyroid hormone (IOPTH) monitoring with a ≥50% drop commonly guides the extent of exploration for primary hyperparathyroidism (pHPT), receiver operating characteristic (ROC) analysis has not been performed to determine whether other criteria yield better sensitivity and specificity. The aim of this study was to identify the optimum percent change of IOPTH following removal of the abnormal parathyroid pathology, in order to predict biochemical cure. Secondary aims were to identify patient subgroups with increased area under the ROC curve (AUC) and the need for moderated criteria.Methods: A retrospective review was performed on patients undergoing primary parathyroid surgery for sporadic pHPT between 1999 and 2010 at a tertiary center for endocrine surgery. Eight hundred and ninety-six patients with primary hyperparathyroidism were included. Multigland disease (MGD) was defined as the intraoperative detection of more than 1 enlarged hypercellular gland or persistent disease after single gland excision. ROC analysis was used to determine the value with the best performance at predicting MGD, following bilateral exploration.Results: MGD was diagnosed in 174 patients (19.4%). ROC analysis demonstrated an AUC of 0.69. An IOPTH drop of 72% was the point of optimal discrimination with a sensitivity of 55% and specificity of 76% for predicting MGD. Subgroup analysis by preoperative calcium, preoperative PTH, localization studies, or pre- and post-excision IOPTH, did not identify any factors associated with an improved AUC.Conclusion: To our knowledge, this is the first study to use ROC analysis in a large patient cohort. An IOPTH drop of 72% was found to have optimal discriminating ability. We failed to identify a subset of patients for whom there was substantial improvement in the AUC, sensitivity, or specificity.Abbreviations: AUC = area under the ROC curve; BE = bilateral neck exploration; FE = focal parathyroid exploration; IOPTH = intraoperative parathyroid hormone; MGD = multigland disease; MIBI = Tc99m-sestamibi I-123 subtraction single-photon emission computed tomography/computed tomography; pHPT = primary hyperparathyroidism; ROC = receiver operating characteristic; SGD = single gland disease; US = surgeon-performed neck ultrasound     

Treatment With Cinacalcet Increases Plasma Adiponectin Concentration in Hemodialyzed Patients With Chronic Kidney Disease and Secondary Hyperparathyroidism

Objective: Cinacalcet increases calcium-sensing receptor (CaSR) sensitivity to serum calcium. CaSR is expressed by adipocytes, and adiponectin is an adipokine with antiatherogenic and insulin-sensitizing properties. The aim of this study was to assess the influence of a 3-month cinacalcet regimen on plasma adiponectin concentration in hemodialyzed patients (HDP) with chronic kidney disease (CKD) and secondary hyperparathyroidism (sHPT).Methods: Plasma adiponectin, advanced oxidation protein products (AOPP), serum interleukin-6 (IL-6) and C-reactive protein (CRP) concentrations were assessed in 65 HDP with sHPT treated with cinacalcet (30–120 mg/day) before the first dose and after 3 months of treatment.Results: There was a significant decrease in serum parathyroid hormone (PTH) concentration: from 1,089 (891–1,286) pg/mL to 775 (574–976) pg/mL after 3 months of treatment (P<.0001). The treatment was associated with a significant (P = .048) increase in plasma adiponectin concentration from 16.9 (14.4–19.5) μg/mL to 17.8 (15.0–20.6) μg/mL. Significant (P = .03) reduction of plasma AOPP concentration was observed from 186.7 (156.7–216.7) pg/mL to 162.6 (141.2–183.9) pg/mL.Conclusions: A 3-month cinacalcet regimen increased plasma adiponectin concentrations in HDP with sHPT. Increased adiponectinemia in these patients may be related to reduced oxidative stress.Abbreviations: AOPP = advanced oxidation protein products BMI = body mass index CaSR = calcium-sensing receptor CKD = chronic kidney disease CRP = C-reactive protein HDP = hemodialyzed patient IL = interleukin PTH = parathyroid hormone sHPT = secondary hyperparathyroidism     

Role of Imaging Tests for Preoperative Location of Pathologic Parathyroid Tissue in Patients with Primary Hyperparathyroidism

Objective: Primary hyperparathyroidism (PHPT) can be cured by parathyroidectomy, and the preoperative location of enlarged pathologic parathyroid glands is determined by imaging studies, especially cervical ultrasonography and scintigraphy scanning. The aim of this retrospective study was to evaluate the use of preoperative cervical ultrasonography and/or parathyroid scintigraphy in locating pathologic parathyroid tissue in a group of patients with PHPT followed in the same endocrine center.Methods: We examined the records of 61 patients who had undergone parathyroidectomy for PHPT following ^99mTc-sestamibi scintigraphy scan and/or cervical ultrasonography. Scintigraphic and ultrasonographic findings were compared to histopathologic results of the surgical specimens.Results: Ultrasonography detected enlarged parathyroid glands in 87% (48/55) of patients with PHPT and ^99mTc-sestamibi scintigraphy in 79% (37/47) of the cases. Ultrasonography was able to correctly predict the surgical findings in 75% (41/55) of patients and scintigraphy in 72% (34/47). Of 7 patients who had negative ultrasonography, scintigraphy correctly predicted the surgical results in 2 (29%). Of 10 patients who had negative scintigraphy, ultrasonography correctly predicted the surgical results in 4 (40%). When we analyzed only patients with solitary eutopic parathyroid adenomas, the predictive positive values of ultrasonography and scintigraphy were 90% and 86%, respectively.Conclusion: Cervical ultrasonography had a higher likelihood of a correct positive test and a greater predictive positive value for solitary adenoma compared to ^99mTc-sestamibi and should be used as the first diagnostic tool for preoperative localization of affected parathyroid glands in PHPT.Abbreviations:Ca = calciumIEDE = Instituto Estadual de Diabetes e Endocrinologia Luiz CapriglionePHPT = primary hyperparathyroidismPTH = parathyroid hormone     

Does Baseline PTH Influence Recovery of Bone Mineral Density,Trabecular Bone Score and Bone Turnover Markers? A Prospective Study Following Curative PArathyroidectomy in Primary Hyperparathyroidism

Objective: This prospective study was carried out to assess trabecular bone score, bone mineral density (BMD), and bone biochemistry in Indian subjects with symptomatic primary hyperparathyroidism (PHPT), and to study the influence of baseline parathyroid hormone (PTH) on recovery of these parameters following curative surgery.Methods: This was a 2-year prospective study conducted at a tertiary care centre in southern India. Baseline assessment included demographic details, mode of presentation, bone mineral biochemistry, BMD, trabecular bone score (TBS), and bone turnover markers (BTMs). These parameters were reassessed at the end of the first and second years following curative parathyroid surgery.Results: Fifty-one subjects (32 men and 19 women) with PHPT who had undergone curative parathyroidectomy were included in this study. The mean (SD) age was 44.6 (13.7) years. The TBS, BTMs, and BMD at lumbar spine and forearm were significantly worse at baseline in subjects with higher baseline PTH (≥250 pg/mL) when compared to the group with lower baseline PTH (<250 pg/mL). At the end of 2 years, the difference between high versus low PTH groups (mean ± SD) persisted only for forearm BMD (0.638 ± 0.093 versus 0.698 ± 0.041 g/cm²; P =.01). However, on follow-up visits in the first and second year after curative parathyroidectomy, there was no significant difference in BTMs, BMD at the femoral neck, lumbar spine, and TBS between the 2 groups stratified by baseline PTH.Conclusion: The BMD at the forearm remained significantly worse in individuals with high baseline PTH even at 2 years after surgery, while other parameters including TBS improved significantly from baseline.Abbreviations: 25(OH)D = 25-hydroxyvitamin D; BMD = bone mineral density; BMI = body mass index; BTMs = Bone turnover markers; CTX = C-terminal telopeptide of type 1 collagen; DXA = dual energy X-ray absorptiometry; P1NP = N-terminal propeptide of type 1 procollagen; PHPT = primary hyperparathyroidism; PTH = parathyroid hormone; TBS = trabecular bone score     

Asymptomatic Primary Hyperparathyroidism Exists in North India: Retrospective Data from 2 Tertiary Care Centers

Objective: Primary hyperparathyroidism (PHPT) has evolved into an asymptomatic disease in the west. In contrast, classic symptoms of PHPT have been reported to be common in the east. Here we describe clinical and biochemical profiles of patients diagnosed with PHPT between 2009 and 2012.Methods: This was a retrospective study conducted at 2 tertiary care centers in north India. All patients who underwent evaluation and surgery for primary hyperparathyroidism (PHPT) from January 2009 to December 2012 were included.Results: A total of 50 patients were studied between 2009 and 2012. Among them 31 (62%) were symptomatic and 19 (38%) were asymptomatic. The mean age (SD) was 48.3 (15.8) years, and the female to male ratio was 1.9:1. None of the patients had brown tumors or bone deformities. The asymptomatic group had significantly lower median adenoma weight (0.57 vs. 3.4 g, P<.05), a higher mean age (57.3 vs. 42.8 years, P<.05), and a lower median intact parathyroid hormone (iPTH) level (254.5 vs. 295 pg/mL, P<.05) compared to the symptomatic group. Adenoma weight was positively correlated with baseline serum calcium, iPTH, and alkaline phosphatase (ALP) levels.Conclusion: The asymptomatic form of PHPT was found in a significant percentage of north Indian patients in this study. Asymptomatic PHPT patients were older in age and had lower parathyroid adenoma weights and iPTH levels compared to symptomatic PHPT patients. Positive correlations were found between parathyroid adenoma weight and serum calcium, iPTH, and ALP levels.Abbreviations: ALP = alkaline phosphatase iPTH = intact parathyroid hormone MIBI = 2-methoxyisobutylisonitrile 25(OH)D = 25-hydroxyvitamin D3 PHPT = primary hyperparathyroidism PTH = parathyroid hormone     

An Unusual Case of Recurrent Hyperparathyroidism and Papillary Thyroid Cancer

ObjectiveTo report an unusual occurrence of recurrent hyperparathyroidism due to papillary thyroid carcinoma.MethodsWe describe the clinical history, physical examination findings, laboratory values, imaging findings, and pathologic findings of a woman who developed recurrent hyperparathyroidism 13 years after successful parathyroidectomy.ResultsA 59-year-old woman presented to our clinic with recurrent primary hyperparathyroidism. In 1994, she presented with nephrolithiasis and underwent resection of a right superior parathyroid adenoma that resulted in clinical and biochemical cure. Her clinical course had been followed at periodic intervals, and she had been symptom-free and normocalcemic. In 2007, she again developed nephrolithiasis and was documented to have recurrent hyperparathyroidism. Imaging studies suggested a parathyroid adenoma near the right inferior pole of the thyroid. The patient had reoperative neck exploration. No obvious parathyroid adenoma was found and a right thyroid lobectomy was performed, which resulted in normalization of intraoperative intact parathyroid hormone levels, and the incision was closed. Final pathology demonstrated no parathyroid adenoma, but instead, a 1-cm papillary thyroid carcinoma that stained positive for parathyroid hormone. More than 6 months after surgery, she remains clinically and biochemically cured.ConclusionsRecurrent hyperparathyroidism occurs secondary to multiple causes. This case demonstrates the challenge a surgeon faces in managing recurrent disease and highlights a rare phenomenon of papillary thyroid cancer causing recurrent hyperparathyroidism. (Endocr Pract. 2009;15:349-352)     

Serum Monocyte Chemokine Protein-1 Levels Before and After Parathyroidectomy in Patients with Primary Hyperparathyroidism

ObjectiveTo investigate the effects of parathyroidectomy on serum monocyte chemokine protein-1 (MCP- 1) levels in patients with primary hyperparathyroidism (PHPT).MethodsForty-three PHPT patients, age 56 ± 12 years, underwent minimally invasive parathyroidectomy. Serum samples were collected at 0 and 15 to 20 minutes after parathyroid adenoma removal. Serum samples were stored at -70°C until time of assay.ResultsIn 40 PHPT patients with a single adenoma, MCP-1 levels decreased from 342 ± 103 to 250 ± 77 pg/ mL (P < .001) 15 to 20 minutes after parathyroid adenoma removal. MCP-1 levels were positively correlated with intact parathyroid hormone (PTH) levels (R = 0.47; P < .01). In 3 PHPT patients with double parathyroid adenoma, MCP-1 levels did not decrease after removal of the first adenoma but decreased 15 to 20 minutes after second adenoma removal.ConclusionOur results provide evidence that the decrease in serum intact PTH due to minimally invasive parathyroidectomy results in an immediate decrease in serum MCP-1 levels. (Endocr Pract. 2014;20:1165-1169)     

KDIGO Categories of Glomerular Filtration Rate and Parathyroid Hormone Secretion in Primary Hyperparathyroidism

Objective: The recent Fourth Workshop on the Management of Asymptomatic primary hyperparathyroidism (PHPT) maintained the threshold of 60 mL/min for decreased renal function, below which surgery is recommended. This study investigated the relationship between different stages of renal insufficiency and parathyroid hormone (PTH) levels in an updated case series of PHPT patients.Methods: This was a retrospective, cross-sectional study involving 379 consecutive PHPT patients. Biochemical evaluation included total and ionized serum calcium, phosphate, creatinine, immunoreactive intact PTH, and 25-hydroxyvitamin D₃ (25[OH]D₃) levels in the fasting state. Glomerular filtration rate (GFR) was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.Results: Mean CKD-EPI estimated GFR was 81.9 ± 20.3 mL/min/1.73 m², and median GFR was 84.0 mL/min/1.73 m² (interquartile range, 26.8 mL/min/1.73 m²). The patients were divided into 5 groups according to the Kidney Disease: Improving Global Outcomes 2012 guidelines: group 1 with normal or increased GFR (>90 mL/min/1.73 m²); group 2 with mild GFR decrease (60 to 89 mL/min/1.73 m²); group 3a with mild to moderate GFR decrease (45 to 59 mL/min/1.73 m²); group 3b with moderate to severe GFR decrease (30 to 44 mL/min/1.73 m²); and group 4 with severe GFR decrease (<30 mL/min/1.73 m²). Among the 5 groups of patients, serum calcium levels were different (P = .025), whereas 25(OH)D₃ levels were not (P = .36). PTH levels were comparable across groups 1 through 3a, but they were significantly higher in groups 3b and 4 (P<.0001).Conclusion: In our series of PHPT patients, PTH levels did not rise as a result of renal impairment until GFR decreased below 45 mL/min/1.73 m².Abbreviations: 25(OH)D₃ = 25-hydroxyvitamin D₃ CKD-EPI = Chronic Kidney Disease-Epidemiology Collaboration GFR = glomerular filtration rate K/DOQI = National Kidney Foundation Disease Outcomes Quality Initiative KDIGO = Kidney Disease: Improving Global Outcomes MDRD = Modification of Diet in Renal Disease PHPT = primary hyperparathyroidism PTH = parathyroid hormone     

Evolution of Surgical Treatment of Primary Hyperparathyroidism in Patients With Multiple Endocrine Neoplasia Type 2A

ObjectiveTo determine the best surgical strategy for patients with multiple endocrine neoplasia type 2A (MEN 2A) who have primary hyperparathyroidism (PHPT).MethodsWe performed a systematic literature review and conducted a retrospective cohort study that included patients with PHPT identified from the MEN 2A database at the University Medical Center of Utrecht, Utrecht, the Netherlands, between 1979 and 2009.ResultsThe review describes the course of worldwide parathyroid surgical management in MEN 2A PHPT over the past 75 years, which has evolved from aggressive parathyroid resections to minimally invasive parathyroidectomy (MIP). The study cohort included 20 patients. Primary surgery for parathyroid disease in patients with MEN 2A (n = 16) included MIP (n = 6), conventional neck exploration with resection of enlarged parathyroid gland(s) (n = 4), and resection of 1 or more enlarged gland(s) during total thyroidectomy (n = 6). Thirteen patients were initially cured after the primary operation. Five patients experi enced persistent or recurrent PHPT. After MIP, 1 patient had persistent PHPT, but no patient developed recurrent PHPT during 5 years of follow-up. Five patients had hypoparathyroidism after subtotal or total parathyroidectomy with autotransplantation, but only 1 patient had transient hypoparathyroidism after MIP. One patient had transient recurrent laryngeal nerve injury after MIP.ConclusionsSurgery for PHPT in patients with MEN 2A has evolved from aggressive conventional exploration of all 4 glands to focused MIP, which appears to be a feasible approach. MIP has low rates of persistent and recurrent PHPT, and the complications are minimal. (Endocr Pract. 2011;17:7-15)     

Primary Hyperparathyroidism: Comparing Between Solid and Cystic Adenomas and the Efficacy of Ultrasound and Single-Photon Emission Computed Tomography in their Diagnosis

Objective: Primary hyperparathyroidism (PHPT) is a disorder that results from abnormal functioning of the parathyroid glands. The purpose of this study was to compare cystic and solid adenomas by analyzing different variables associated with PHPT and parathyroid adenomas (age, calcium, phosphorus, and parathyroid hormone &lsqb;PTH] levels, adenoma volume) while comparing the efficacy of ultrasound and single-photon emission computed tomography in differentiating between both types of adenoma.Methods: From 152 patients diagnosed with PHPT between January 2013 and 2014, only 109 patients who had positive ultrasonographic findings for single parathyroid adenoma were included in the study.Results: A total of 26 patients had cystic adenomas and 83 patients had solid adenomas. Sestamibi (MIBI) was negative in 50% of the cystic adenoma group and 27.7% of the solid adenoma group, with an overall technetium-MIBI efficacy of 67%. Age, phosphorus level, and adenoma volume were significantly higher in patients with cystic adenomas (P = .001, P = .02, and P = .02, respectively), whereas calcium and PTH levels were significantly higher in patients with solid adenomas (P = .02, P = .038, respectively). MIBI had a significant correlation with PTH levels (P = .031) and adenoma volume (P = .05) only in patients with solid adenomas. No significant correlation was found between sex and type of parathyroid adenoma.Conclusion: The current study is the first to compare age, PTH levels, and adenoma volume between cystic and solid adenoma patients, providing more information for the poorly understood pathology of cystic adenomas. Our findings showed that age and calcium and PTH levels are significantly higher in patients with solid adenomas, whereas adenoma volume and phosphorus levels are significantly higher in patients with cystic adenomas.Abbreviations: BMD = bone mineral density GFR = glomerular filtration rate iPTH = intact parathyroid hormone MIBI = sestamibi PHPT = primary hyperparathyroidism PTH = parathyroid hormone SPECT = single-photon emission computed tomography Tc = technetium US = ultrasound     

Imaging Localization and Surgical Approach in the Management of Ectopic Parathyroid Adenomas

Objective: (1) Review the anatomy and epidemiology of ectopic parathyroid adenomas (EPAs), (2) summarize the role of relevant imaging modalities in the localization of EPAs, and (3) characterize surgical approaches for various ectopic locations.Methods: Literature review of published English-language articles from 1995 through August 2017.Results: Summary of the literature indicates that the prevalence of EPA is approximately 20% in unexplored patients with primary hyperparathyroidism, but it is as high as 66% in re-operative patients. EPAs may be located anywhere from the carotid bifurcation to the aorto-pulmonary window. Ultrasound has limited accuracy in identifying EPAs except near the thyroid and thyrothymic ligament and requires expert experience from the user. Among dual-phase ^99mTc sestamibi scintigraphy techniques, hybrid imaging with both single-photon emission computed tomography (SPECT) and computed tomography (CT) (SPECT/CT) is superior to planar scintigraphy or SPECT alone at localizing EPAs. Four-dimensional computed tomography (4DCT) precisely delineates important anatomic relationships and is highly sensitive in localizing EPAs. Although 4DCT requires radiation, intravenous iodinated contrast, and reader experience, it is well-equipped to detect lesions at various ectopic sites and guide the surgical approach. EPAs frequently require alternative surgical approaches. Re-operative parathyroidectomy may be attempted in patients having previously undergone bilateral neck exploration by an experienced surgeon once the lesion is colocalized by 2 repeat imaging modalities. Removal of nonlocalized disease requires a careful and systematic exploration of superior and inferior gland locations.Conclusion: EPAs pose challenges during both localization and surgical removal. High-volume experience and multidisciplinary care are necessary for optimal outcomes.Abbreviations: CT = computed tomography; 4DCT = 4-dimensional CT; EPA = ectopic parathyroid adenoma; EPG = ectopic parathyroid gland; PHPT = primary hyperparathyroidism; RLN = recurrent laryngeal nerve; SPECT = single-photon emission computed tomography; TE = tracheo-esophageal     

Associations of Serum Ionized Calcium,Phosphate, and Pth Levels with Parathyroid Scan in Primary Hyperparathyroidism

Objective: To evaluate the relationship between various biochemical parameters in patients with primary hyperparathyroidism (PHPT) with positive and negative technetium-99 sestamibi (Tc) parathyroid scans performed with single-photon emission computed tomography/computed tomography (SPECT/CT).Methods: This retrospective analysis was used to develop a logistic probability model. It included 218 patients with PHPT. The main outcome measures were serum total calcium, ionized calcium, intact parathyroid hormone (PTH), albumin, alkaline phosphatase, phosphate, 25-hydroxy vitamin D, 1,25-dihydroxy vitamin D, 24-h urinary calcium levels, and parathyroid adenoma weight.Results: Individually, using cut-off levels of 6.0 mg/dL for ionized calcium, 3.0 mg/dL for phosphate, and 90 pg/mL for intact PTH, we found that 91.3% (P = .005), 70.7% (P = .004) and 87.90% (P = .023) of the patients had a positive Tc scan with their corresponding strengths of associations in the parentheses. Similar significant associations were sustained in multivariate setting for serum ionized calcium (P = .015), phosphate (P = .016), and intact PTH (P = .028). A logistic probability model was designed to predict the probability of being positive for Tc scan given a set of covariates.Conclusion: There are significant associations between the levels of serum ionized calcium, phosphate, intact PTH, and Tc scan positivity. Further studies with larger patient populations are needed.Abbreviations: BMI = body mass index; CT = computed tomography; CV = coefficient variation; DXA = dual-energy x-ray absorptiometry; MRI = magnetic resonance imaging; PHPT = primary hyperparathyroidism; PPV = positive predictive value; PTH = parathyroid hormone; SPECT = single-photon emission computed tomography; Tc = technetium-99 sestamibi     

Primary hyperparathyroidism and familial hypocalciuric hypercalcemia: relationships and clinical implications

ObjectiveTo discuss the unusual occurrence of both familial hypocalciuric hypercalcemia (FHH) and primary hyperparathyroidism in the same patient and to explore potential mechanisms of association and issues related to clinical management.MethodsWe discuss the diagnosis, compare the clinical presentations of FHH and primary hyperparathyroidism, review the literature regarding patients who have presented with both disorders, and discuss management considerations. We also describe 2 patients who have both FHH (confirmed by genetic testing for a mutation in the gene encoding the calcium-sensing receptor [CASR]) and primary hyperparathyroidism.ResultsThe occurrence of both FHH and primary hyperparathyroidism in the same patient has been reported in a few cases, including 2 patients described here, one of whom was documented to have a novel CASR mutation. Inthose with clinical sequelae of hyperparathyroidism, parathyroidectomy has led to reduction, but not normalization, of serum calcium levels.ConclusionsThe coexistence of FHH and primary hyperparathyroidism should be considered in patients with hypercalcemia, hypophosphatemia, frankly elevated parathyroid hormone levels, and low urinary calcium excretion. Genetic testing for inactivating CASR gene mutations can confirm the diagnosis of FHH. Although surgical intervention does not resolve hypercalcemia, it may be beneficial by reducing the degree of hypercalcemia, alleviating the symptoms, and preventing potential complications of hyperparathyroidism. (Endocr Pract. 2012;18:412-417)