Association between parathyroid hormone (PTH)/PTH-related peptide receptor gene polymorphism and the extent of bone mass reduction in primary hyperparathyroidism.

Genetic contributions to bone mineral density (BMD) and bone turnover are well known. In the present study, we analyzed the relationship between polymorphism of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor gene existing in exon M7 and the clinical characteristics of primary hyperparathyroidism (pHPT). PTH/PTHrP receptor genotypes were analyzed in 92 pHPT patients by direct sequence to determine whether nucleotide 1417 of the cDNA was C or T. BMD levels at the lumbar spine and at the radius before and one year after parathyroidectomy, as well as serum levels of calcium, phosphorus, alkaline phosphatase (ALP) and intact PTH were measured. Although there were no significant differences in serum levels of calcium, phosphorus and intact PTH, ALP was significantly lower in the CT genotype compared with the TT genotype. BMD level at the radius was significantly higher in the CT genotype than in the CC genotype. Moreover, an increase in radial BMD one year after parathyroidectomy was significantly less in CT genotype than two other genotypes (CC, TT). The present study is the first to indicate that the polymorphism of PTH/PTHrP receptor gene is closely related to the extent of bone mass reduction in pHPT and that this polymorphism would be one of the genetic factors responsible for the severity of the pathological state of pHPT.     

Ultrasound-Guided Radiofrequency Ablation for the Treatment of Primary Hyperparathyroidism: An Efficacy and Safety Study

ObjectiveTo evaluate the efficacy and safety of radiofrequency ablation (RFA) for the treatment of primary hyperparathyroidism (pHPT).MethodsOur study enrolled 25 patients who were treated with RFA for pHPT from September 2015 to January 2020. The serum intact parathyroid hormone (iPTH), calcium, and phosphate levels were tested within 1 week before RFA and at 1 day, 1 month, 3 months, 6 months, and 12 months after ablation. The ablation areas were evaluated using ultrasound at 1, 3, 6, and 12 months after RFA. Postoperative complications, including voice hoarseness, hematoma, postoperative pain, incision infections, hypoparathyroidism, and hypocalcemia, were recorded.ResultsA total of 25 patients with pHPT (mean age, 53.9 ± 10.9 years; 22 women and 3 men) with 29 enlarged parathyroid glands were treated with RFA. Of the 25 patients, 22 were treated in 1 session and 3 were treated in 2 sessions. Serum iPTH and calcium levels decreased significantly on day 1 after RFA (all P < .05). A total of 21 patients had normal levels of serum iPTH and calcium after RFA, with a cure rate of 84%. At the 12-month follow-up, 26 treated parathyroid glands exhibited a volume reduction rate of >70%. There were only a few minor complications, including 4 cases of postoperative pain (in 4 of the 25 patients [16%]) and 1 case of mild postoperative transient hypocalcemia (in 1 of the 25 patients [4%]).ConclusionUltrasound-guided RFA is an effective and safe technique for the treatment of carefully selected patients with pHPT. However, larger sample size and longer follow-up are still needed to further confirm its clinical value.     

Preoperative Calcium and Parathyroid Hormone Values Are Poor Predictors of Gland Volume and Multigland Disease in Primary Hyperparathyroidism: A Review of 2000 Consecutive Patients

ObjectiveCalcium and parathyroid hormone (PTH) values are believed to have a linear relationship in patients with primary hyperparathyroidism and correlate with parathyroid gland size, with higher values predicting single-gland disease. In this modern series, these preoperative values were correlated with operative findings to determine their utility in predicting the gland involvement at parathyroid exploration.MethodsTwo thousand consecutive patients who underwent initial surgery for sporadic primary hyperparathyroidism from 2000 to 2014 were reviewed. All patients underwent a 4-gland exploration. Relationships between preoperative calcium and PTH values with the total gland volume of each patient were examined and stratified using the number of involved glands: single adenoma (SA), double adenoma (DA), and hyperplasia (H).ResultsThere were 1274 (64%) SA, 359 (18%) DA, and 367 (18%) H cases. There was a poor correlation between preoperative calcium and PTH values (R = 0.37) and both poorly correlated with the total gland volume (R < 0.40). Similarly, subgroup analysis using the number of involved glands showed poor correlation. The mean total gland volume was similar among all subgroups (SA = 1.28 cm³, DA = 1.43 cm³, and H = 1.27 cm³; P = .52), implying that individual glands were smaller in multigland disease. SA was found in 271 (53%) of patients with calcium levels of ≤10.5 mg/dL and 122 (78%) with levels of ≥12 mg/dL (P < .001).ConclusionThis is the largest series correlating preoperative calcium and PTH values with operative findings of gland size and number of diseased glands. Although a lower calcium value predicts somewhat more multigland disease, the overall poor correlation should make the parathyroid surgeon aware that gland size and multigland disease cannot be predicted by preoperative laboratory testing.     

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     

Evaluation of Epicardial Fat Tissue Thickness in Patients with Primary Hyperparathyroidism

ObjectivePrimary hyperparathyroidism (pHPT) affects the cardiovascular system, and epicardial fat tissue (EFT) thickness is closely associated with cardiovascular diseases and atherosclerosis. Despite this, the association between EFT thickness and pHPT has not been studied in a clinical setting. This study aimed to assess EFT thickness in patients with pHPT.MethodsThe study included 38 patients with pHPT and 40 healthy controls. EFT thickness, carotid intima-media thickness (CIMT), serum levels of parathormone (PTH) and calcium, and blood chemistry profiles were determined in all subjects. Correlation and regression analyses were performed with EFT thickness and CIMT as dependent variables and age; systolic and diastolic blood pressure; body mass index (BMI); presence of diabetes mellitus; and free plasma glucose (FPG), PTH, and serum calcium (Ca) levels as independent variables.ResultsBoth the mean EFT thickness and the mean CIMT were significantly greater in the pHPT group than the control group (P < .001 for both). Correlation analysis showed that EFT thickness was significantly correlated with CIMT, age, systolic blood pressure, and PTH and serum Ca levels. Furthermore, the regression analysis revealed that EFT thickness retained its independent and positive association with FPG and serum Ca levels.ConclusionsThe results of this study indicate that EFT thickness may be a useful marker of early atherosclerosis in patients with pHPT. Furthermore, the increase in EFT thickness appears to be due to hypercalcemia. (Endocr Pract. 2014;20:26-32)     

Calcium-Creatinine Clearance Ratio is not Helpful in Differentiating Primary Hyperparathyroidism from Familial Hypercalcemic Hypocalciuria: A Study of 1,000 Patients

Objective: With increasing recognition of more subtle presentations of primary hyperparathyroidism (pHPT), laboratory values are frequently seen in a range that would be expected for patients who have familial hypercalcemic hypocalciuria (FHH). Calcium-creatinine clearance ratio (CCCR) has been advocated as a diagnostic tool to differentiate between these two disorders. However, it is limited by an indeterminate range (0.01 to 0.02). The aim of this study was to assess the relevance of CCCR in a modern series of patients with surgically managed pHPT.Methods: We performed a retrospective cohort study of 1,000 patients who underwent parathyroid surgery for pHPT over 11 years. CCCR was evaluated by degree of biochemical derangement, single versus multiple gland disease, and interfering medications.Results: Patient demographics and resected histopathology were typical for a current series of patients with pHPT. In retrospect, none of the patients were suspected to have FHH postoperatively. CCCR was <0.01 for 19.0%, between 0.01 and 0.02 for 43.7%, and >0.02 in 37.3%. Distribution of CCCR for patients free from interfering medications and different histologic subtypes were the same. One-third of the cohort had mild calcium elevations, more typical for FHH. Of these, almost two-thirds had a CCCR in a range suspect for FHH (<0.02).Conclusion: To our knowledge, this is the largest series to evaluate the validity of CCCR for patients with surgically confirmed pHPT. The utility of CCCR in screening for FHH is limited, as 63% of modern patients with confirmed pHPT have low values.Abbreviations: CaSR = calcium sensing receptor; CCCR = calcium-creatinine clearance ratio; CeE = calcium excretion; FHH = familial hypercalcemic hypocalciuria; pHPT = primary hyperparathyroidism; PTH = parathyroid hormone     

Suppressibility of Parathyroid Hormone in Primary Hyperparathyroidism

ObjectiveTo describe an unusual case of pathologically confirmed primary hyperparathyroidism in a patient presenting with severe hypercalcemia and an undetectable parathyroid hormone (PTH) level.MethodsWe present a detailed case report and outline the serial laboratory findings. In addition, the possible causes of low serum PTH levels in the setting of primary hyperparathyroidism are discussed.ResultsA 16-year-old female patient presented with severe epigastric pain, found to be attributable to acute pancreatitis. At hospital admission, her serum calcium concentration was high (14.0 mg/dL); the patient also had a normal serum phosphorus level of 3.6 mg/dL and an undetectable PTH level (< 0.2 pmol/L). An evaluation for non-PTH-mediated causes of hypercalcemia revealed a partially suppressed thyroid-stimulating hormone concentration and a below normal 1,25-dihydroxyvitamin D level, consistent with her suppressed PTH. One week after the patient was dismissed from the hospital, repeated laboratory studies showed a serum calcium value of 11.1 mg/dL, a serum phosphorus level of 2.8 mg/dL, and an elevated PTH concentration of 11.0 pmol/L, consistent with primary hyperparathyroidism. A repeated 1,25-dihy-droxyvitamin D measurement was elevated. A parathyroid scan showed a parathyroid adenoma in the left lower neck area, and she subsequently underwent successful surgical resection of a pathologically confirmed parathyroid adenoma.ConclusionThis case demonstrates that the serum PTH level can be suppressed in patients with primary hyperparathyroidism. Moreover, it emphasizes the need for careful evaluation of the clinical context in which the PTH measurement is determined. Consideration should be given to repeating measurement of PTH and serum calcium levels when the initial laboratory evaluation of hypercalcemia is unclear because dynamic changes in calcium metabolism may occur in the presence of secondary contributing factors. (Endocr Pract. 2007;13:785-789)     

Intérêt de l’interprétation collégiale de l’échographie cervicale,de la scintigraphie 99mTc-MIBI et de la TEP-TDM à la 18-Fluorocholine dans l’hyperparathyroïdie primaire : expérience du service de médecine nucléaire de l’hôpital Cochin

ObjectivesThis study aims to assess performances of preoperative conventional imaging (99mTc-MIBI scintigraphy, cervical Ultrasonography) and 18F-fluorocholine PET/CT (FCH PET/CT) exams in the detection of hyperfunctioning parathyroid gland(s) in patients operated from primary hyperparathyroidism (pHPT).MethodsBefore surgery, 51 consecutive patients with biochemically confirmed pHPT had successively cervical ultrasonography (cUS), 99mTc-MIBI scintigraphy and FCH PET/CT, all performed in the same Nuclear Medicine Department. 99mTc-MIBI scintigraphy were performed immediatly after cUS and interpreted by same operators. FCH PET/CT exam were interpreted independently by two nuclear medicine physicians. An additional interpretation session integrating the three imaging modalities read in consensus as a combined imaging set was performed.ResultsAt surgery, 69 lesions were removed: 32 parathyroid adenoma and 37 parathyroid hyperplasia. 70% of patients had single-gland disease and 30% had multiglandular disease at histopathology analysis. In the patient-based analysis, sensitivity and accuracy in the detection of single gland disease) for FCH PET/CT, cUS and for 99mTc-MIBI scintigraphy were 86% [0.71–0.94] and 86% [0.70–0.95], 69% [0.52–0.81] and 69% [0.51–0.83], 40% [0.26–0.56] and 40% [0.24–0.58], respectively. Sensitivity and accuracy of the combined imaging set for the detection of single gland disease were 94% [0.81–0.99] and 94% [0.81–0.99].ConclusionOur results suggest that cUS/99mTc-MIBI scintigraphy and FCH PET/CT interpreted during a comprehensive session could be the ideal practice to precisely localize parathyroid lesion(s) in patients with pHPT before surgery.     

Marathon related death due to brainstem herniation in rehydration-related hyponatraemia: a case report

Introduction

The natural history of patients with spontaneous parathyroid necrosis is unknown. In this case report we describe the clinical course, laboratory, radiographic, bone densitometry tests, parathyroid ultrasonography and scintigraphy examinations of a patient performed over a period of eight years after she first presented with a sudden episode of spontaneous resolution of primary hyperparathyroidism (PHPT).

Case presentation

A 24-year-old woman with a clinical history and laboratory and radiographic tests compatible with PHPT suffered a sudden episode of cervical pain and presented with clinical evidence of hypocalcemia. Biopsy of a cervical nodule revealed necrotic material compatible with ischemia of the parathyroid. The follow-up of the patient presented four distinct phases: the first, which lasted two years, was compatible with a period of bone hunger during which it was necessary to introduce calcitriol and calcium carbonate. During this period, the patient showed bone mass gain. The second phase was characterized by normalization of calcium and parathyroid hormone levels and its end was difficult to define. During the third phase there was a recurrence of hypercalcemia associated with elevated parathyroid hormone (PTH) levels and loss of bone mass. The last phase corresponded to the interval after parathyroidectomy, which was characterized by normalization of serum levels of calcium and PTH, as well as bone mass gain.

Conclusion

This case report indicates that spontaneous resolution of PHPT by adenoma necrosis is potentially temporary. Thus, in cases in which a conservative approach is chosen, clinical and laboratory follow-up is indispensable. Bone mass measurement is a useful tool in the follow-up of these cases. However, this option exposes the patient to a potential roller-coaster ride of bone mass gain and loss, whose long term consequences are still unknown.     

Decreased levels of ionized calcium one year after hemithyroidectomy: importance of reduced thyroid hormones

BACKGROUND: Previously we have found reduced levels of total serum calcium and 1,25(OH)2D3 despite an unaltered stimulated parathyroid hormone (PTH) secretion 1 year after hemithyroidectomy. The present study was undertaken to elucidate the possible relationship between calcium homeostasis, thyroid hormones and bone resorption in a group of 45 consecutive patients subjected to hemithyroidectomy because of a solitary nodule. All patients had free T4 and T3 levels within normal range preoperatively. METHODS: Thyroid hormones, bone mineral and biochemical variables known to reflect calcium homeostasis were studied. Patients were divided into three separate groups depending on their pre- and postoperative thyroid hormone status. RESULTS: One year postoperatively, serum levels of free T4 were decreased and that of thyrotropin (TSH) increased in the entire group of patients. The concentration of ionized calcium was reduced from 1.25 +/- 0.05 to 1.22 +/- 0.04 (p < 0.001) despite an unaltered PTH value (2.8 +/- 1.0 vs. 3.1 +/- 1.5, p = 0.50). A significant reduction in C-terminal telopeptide type 1 collagen (1CTP) indicated decreased bone resorption 1 year after surgery (p < 0.05). Subgroup analysis showed that a reduction in ionized calcium was seen only among patients with a postoperative decrease in free T4. Patients with subclinical hyperthyroidism preoperatively presented the lowest postoperative levels of ionized calcium, significantly reduced levels of 1CTP and increased levels of phosphate and creatinine. Multiple linear regression analysis showed that age (p < 0.05) and postoperatively changed serum levels of TSH (p < 0.05), creatinine (p < 0.05), phosphate (p < 0.001) and FT4 (p < 0.01) were independently associated with altered levels of ionized calcium. CONCLUSION: We conclude that the reduction in ionized calcium 1 year after hemithyroidectomy was not due to PTH deficiency. Instead our results suggest that the reduced effects of thyroid hormones on bone and kidney function is essential.     

Serum intact parathyroid hormone concentration measured by a two-site immunoradiometric assay in normal subjects and patients with various parathyroid disorders.

Serum intact parathyroid hormone (PTH) concentration was measured by a two-site immunoradiometric assay (IRMA) in normal subjects and patients with various parathyroid disorders. Serum intact PTH levels were all within the detection limit of the IRMA in normal subjects, and there was a significant negative correlation between serum calcium (Ca) and intact PTH levels. Although 3 out of 26 patients (11.5%) with primary hyperparathyroidism had a normal serum intact PTH concentration, these patients could be readily discriminated from normal subjects by plotting serum intact PTH against the serum Ca concentration. In contrast, serum intact PTH was undetectable in 16 out of 17 patients (94.1%) with idiopathic hypoparathyroidism. Patients with pseudohypoparathyroidism (PHP) type I, mostly under treatment with active vitamin D, exhibited wide distribution of serum intact PTH concentration, and appeared to belong to two distinct subgroups. One group of patients demonstrated a similar relationship between serum intact PTH and Ca levels to normal subjects. The other exhibited much higher serum intact PTH levels despite a normal serum Ca concentration, and no obvious relationship could be observed between the two parameters. These results demonstrate that an inverse relationship between serum Ca and intact PTH can be demonstrated in normal subjects with normocalcemia, that most of the parathyroid disorders can be diagnosed by measuring serum Ca and the intact PTH concentrations simultaneously, and that patients with PHP can be divided into two subgroups: one with a normal relationship between serum Ca and intact PTH, and the other with a high serum PTH level in the face of normocalcemia.     

Clinical use of calcimimetics in the treatment of hyperparathyroidisms

Recognition of the role of the extracellular calcium sensing receptor (CaR) in mineral metabolism has greatly improved our understanding of calcium homeostasis. The activation of this receptor by small changes in the extracellular ionized calcium concentration (Ca(2+)ec) regulates parathormone (PTH) and calcitonin secretion, urinary calcium excretion and ultimately bone turnover. Cloning of CaR and discovery of mutations making the receptor less or more sensitive to calcium allowed a better understanding of several hereditary disorders characterized either by hyperparathyroidism or hypoparathyroidism. CaR became an ideal target for the development of compounds able to modulate the activity of CaR, activators (calcimimetics) as well as inhibitors (calcilytics). The calcimimetics are able to amplify the sensitivity of the CaR to Ca(2+)ec, suppressing PTH levels with a resultant fall in blood Ca2+. They dose-dependently reduce the secretion of PTH in vitro in cultured parathyroid cells, in animal models and in humans. In uremic animals, these compounds prevent parathyroid cell hyperplasia, normalize plasma PTH levels and bone remodelling. In uremic patients undergoing hemodialysis, the calcimimetics reduce plasma PTH concentration at short-term (12 weeks) as well as at long-term (2 years), serum calcium-phosphorus product and bone remodelling. After one year of treatment, these patients show a gain of bone mass of 2-3% at the femoral neck and at the total body. Contrarily, the calcilytics, by inhibiting CaR, can intermittently stimulate the secretion and the serum concentration of PTH. This results in an skeletal anabolic effect with a substantial increase in bone mineral density. They are potentially very interesting for the treatment of post-menopausal osteoporosis.     

Three large, functioning cystic parathyroid adenomas

ObjectiveTo report a very rare case of 3 large, functioning cystic parathyroid adenomas causing primary hyperparathyroidism.MethodsWe present the history, clinical findings, laboratory test results, radiologic findings, endocrine workup results, intraoperative surgical challenges, and surgical pathology report of the study patient. We review the literature and discuss the importance of intraoperative parathyroid hormone (PTH) measurement in such cases.ResultsA 79-year-old woman presented with primary hyperparathyroidism and elevated levels of calcium and PTH. Localization studies confirmed the presence of a large right upper parathyroid adenoma. On exploration, a very large cystic parathyroid gland was identified at that location. Because intraoperative PTH levels remained elevated, further exploration was pursued, which revealed 2 more large cystic glands on the left side that were resected. This resulted in an adequate but slow PTH drop. The right lower gland appeared normal. On follow-up 4 days and 6 weeks after surgery, the calcium and PTH levels had normalized.ConclusionThis case highlights the aspects of intraoperative PTH use and underscores the need to exclude multigland disease even in the setting of a very large parathyroid cyst with concordant localization studies. (Endocr Pract. 2012;18:e14-e16)     

Plasma parathyroid hormone during acute volume expansion in the rat

Various studies have suggested the possibility that volume expansion may increase parathyroid hormone (PTH) secretion. PTH appears to have renal effects consistent with the actions of a natriuretic and diuretic and the possibility exists that PTH may play a physiological role in volume homeostasis. The present studies were designed to examine whether PTH levels in plasma from rats was influenced by acute volume expansion and whether such effects were independent of alterations in plasma ionized calcium concentration. Volume expansion with calcium-free bicarbonate Ringers (10% of body weight, IV) led to a drop in plasma ionized calcium from 1.08 to 0.92 mMol/l (p less than 0.01) while plasma PTH concentration was increased from 67.2 to 114.2 pMol/l. Volume expansion with bicarbonate Ringers solution (also 10% of body wt, IV) which contained 1.8 mM CaCl2 was not associated with any significant change in either plasma ionized calcium or plasma PTH concentration. However, measurements of blood packed cell volume (PCV) revealed that infusion resulted in a drop in PCV from 49.7 to 41.1% (p less than 0.01). This represents a dilution of plasma of approximately 42%. The absence of any drop in plasma PTH during isocalcemic volume expansion suggests an underlying stimulus to PTH secretion during volume expansion independent of plasma ionized calcium levels.     

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     

Parathyroid Hormone Level Changes Following Radioiodine Therapy for Thyroid Cancer: A Prospective Observational Study

ObjectiveOur objective was to analyze the effect of radioiodine (RAI) therapy on parathyroid hormone (PTH) secretion.MethodsA total of 137 patients were included and divided into 2 groups based on pretherapy PTH levels. The residual thyroid tissue volume was classified into 4 grades (0-3), and a value of 0 indicated that there was no apparent residual tissue. We analyzed the PTH level changes among different time points in each group and the factors that could predict the PTH level changes.ResultsIn 113 patients with normal parathyroid gland function, the PTH level at baseline, 1 day, 7 days, 1 month, 3 months, and 6 months after RAI therapy did not show any significant difference; in 24 patients with decreased parathyroid gland function, the level of PTH immediately decreased after the implementation of RAI therapy but gradually returned to a pre-RAI therapy level within 6 months. On the seventh day after therapy, the mean value of PTH in patients with a residual thyroid tissue volume of extent of 0/1 was 8.0 ± 2.3 pg/mL, which was significantly higher than that in patients with a residual thyroid tissue volume of extent of 2/3 (P = .011). Similar phenomena were observed 1 month, 3 months, and 6 months after therapy.ConclusionRAI therapy had a significant transient adverse effect on parathyroid gland function in patients with decreased PTH secretion pretherapy, and the extent was associated with the amount of residual thyroid tissue.     

The Detection of Preoperative Parathyroid Lesions: The Success of Ultrasonography,Technetium-99m Methoxyisobutylisonitrile Parathyroid Scintigraphy,and Single-Photon Emission Computed Tomography–Computed Tomography

ObjectiveWe aimed to find and compare the efficacy of ultrasonography (US), technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy (MIBI-S), and single-photon emission computed tomography–computed tomography (SPECT-CT) in detecting the localization of parathyroid adenomas in patients with primary hyperparathyroidism.MethodsIn total, 348 patients were included in this study. Preoperative parathyroid imaging with US, MIBI-S, and SPECT-CT was evaluated and compared with operative findings. The results of the imaging methods were compared with pathology and operation reports.ResultsIn 318 patients (91.3%), one of the imaging methods was able to localize the lesion correctly. US detected the localization of the parathyroid lesions correctly in 268 patients (77%), whereas SPECT-CT and MIBI-S were correct in 254 (73%) and 209 (60%) patients, respectively. There was a statistically significant relationship between the parathyroid hormone (PTH) level and 3 imaging methods’ success rates (P < .05). The PTH cut-off value, which best determined the correct localization, was 152.5 pg/mL for US, 143 pg/mL for MIBI-S, and 143 pg/mL for SPECT-CT. It was observed that the correct localization rate for parathyroid lesions increased with higher PTH levels.ConclusionIn our study population, US was more successful, in most cases, than other imaging methods in localizing parathyroid lesions but SPECT-CT was more accurate in localizing mediastinal lesions. In addition, it was found that preoperative PTH levels affect the accuracy of imaging methods.     

A Retrospective Study of Ultrasonography in the Investigation of Primary Hyperparathyroidism: A New Perspective for Ultrasound Echogenicity Features of Parathyroid Nodules

ObjectiveTo identify and understand parathyroid lesions of patients with primary hyperparathyroidism (PHPT) more accurately under ultrasound.MethodsThis retrospective study involved 423 adult patients with PHPT with a single parathyroid nodule and positive parathyroid ultrasonography between 2018 and 2019. The clinical characteristics of the study patients and histopathologic sections were reviewed.ResultsAccording to the main grayscale echogenicity features of parathyroid nodules, 423 cases were divided into groups: iso-hyperechogenicity solid (61/423), hypoechogenicity solid (304/423), and mixed-echogenicity cyst-solid (58/423) groups. Comparison among the 3 groups showed that the iso-hyperechogenicity group included more asymptomatic patients with PHPT and fewer patients with severe symptoms like bone fractures (P < .05). The mixed-echogenicity group showed higher median serum parathyroid hormone (PTH) and serum calcium levels and larger lesion sizes (P < .05), and the iso-hyperechogenicity group showed the lowest median serum PTH level. No difference in lesion size was noted between the 2 solid groups, but the median serum PTH level in the hypoechogenicity group was higher than that in the iso-hyperechogenicity group (P < .05). According to histopathology, the hypoechogenic area of the samples may contain more functional components (chief cells), whereas the iso-hyperechogenic area has more nonfunctional components (eg, lipocytes and connective tissues).ConclusionThe PHPT nodules distinguished by ultrasound echogenicity features showed different histopathologic components, reflected by different clinical characteristics of the patients with PHPT.     

Calcium metabolism in post-menopausal women

To investigate some parameters involved in postmenopausal calcium metabolism we have measured FSH, LH, estradiol (E2), parathyroid hormone (PTH) calcitonin (CT), 25-hydroxy-vitamin D3 (25-OH-D3), total calcium (CaT) and ionic calcium (Ca++) serum levels in 20 healthy postmenopausal women and 20 premenopausal women. The results reported show that the decrease of estradiol levels are associated with a significant decrease in 25-OH-D3 serum levels, possibly as result of a lower concentration of vitamin D binding protein, which is extremely sensitive to changes in oestrogen levels. The PTH levels were similar in both groups studied, which might be explained together with increased ionic calcium levels in postmenopausal women, by decreased parathyroid sensitivity to the blocking action of Ca++.     

Percutaneous ethanol injections in the treatment of secondary hyperparathyroidism

INTRODUCTION: Renal insufficiency is the most common etiology of secondary hyperparathyroidism. In case of resistance for conservative treatment, methods of choice are surgical intervention or percutaneous ethanol injections. AIM OF THE STUDY: The aim of the study was to evaluate usefulness of percutaneous ethanol injection therapy in the treatment of patients with secondary hyperparathyroidism. MATERIAL AND METHODS: We performed percutaneous 96% ethanol injections under USG guideance in 51 patients: 22 women (mean age 49.6 years) and 29 men (46.6 yrs). The base level of parathormone was 689.35 pg/ml. We managed to visualize one parathyroid gland in 34 patients, 2 in 12, 3 in 5 patients. The mean volume of a single gland was 0,8 cm3. All the injections were performed with the use of needle number 6. We repeated injections in case of no effects. One injection was performed in 18 patients, 2 in 18, 3 in 13, 5 in 1 and 6 in 1 patient. Before and after the treatment patients were examined with USG, scintigraphy and densitometry. Serum levels of calcium (Ca), phosphorus (P), parathormone (PTH) and alkaline phosphatase (FA) activity were also obtained. The main criteria for success was decrease in parathormone level of 50% or more in comparison with pre-injection level or to less than 200 pg/ml. RESULTS: In the whole group of patients after the first month, positive results were observed in 67%. There were no changes in 23%, and PTH level increased in 10%. After 6 months-positive results in 53%, no change in 35% and increase in 12%. We noted the best results in patients with PTH less than 800 pg/ml-72% of them had positive results after 1 as far as after the 6 month. CONCLUSIONS: Percutaneous ethanol injections are valuable method of treatment of secondary hyperparathyroidism. The best results can be obtained if PTH level is less than 800 pg/ml, one parathyroid gland dominating over the rest is visualised in USG, and if patient responds after 1 or at least 2 injections.