Clinical practice. Primary hyperparathyroidism

Imaging Recommendations for Diagnosis and Management of Primary Parathyroid Pathologies: A Comprehensive Review

Parathyroid pathologies are suspected based on the biochemical alterations and clinical manifestations, and the predominant roles of imaging in primary hyperparathyroidism are localisation of tumour within parathyroid glands, surgical planning, and to look for any ectopic parathyroid tissue in the setting of recurrent disease. This article provides a comprehensive review of embryology and anatomical variations of parathyroid glands and their clinical relevance, surgical anatomy of parathyroid glands, differentiation between multiglandular parathyroid disease, solitary adenoma, atypical parathyroid tumour, and parathyroid carcinoma. The roles, advantages and limitations of ultrasound, four-dimensional computed tomography (4DCT), radiolabelled technetium-99 (99mTc) sestamibi or dual tracer 99mTc pertechnetate and 99mTc-sestamibi with or without single photon emission computed tomography (SPECT) or SPECT/CT, dynamic enhanced magnetic resonance imaging (4DMRI), and fluoro-choline positron emission tomography (18F-FCH PET) or [11C] Methionine (11C -MET) PET in the management of parathyroid lesions have been extensively discussed in this article. The role of fluorodeoxyglucose PET (FDG-PET) has also been elucidated in this article. Management guidelines for parathyroid carcinoma proposed by the American Society of Clinical Oncology (ASCO) have also been described. An algorithm for management of parathyroid lesions has been provided at the end to serve as a quick reference guide for radiologists, clinicians and surgeons.

Parathyroid carcinoma located in the thyroid gland: A case report

BACKGROUND

Parathyroid carcinoma (PC) is a difficult-to-diagnose rare disease with low incidence. Relatively accurate preoperative diagnosis is very important in choosing surgical methods and patient prognosis.

CASE SUMMARY

This study reported the clinical diagnosis and treatment of a rare patient with PC located in the thyroid gland and provided a case reference for the diagnosis and treatment of PC. A case of a 64-year-old male patient who presented to our hospital with systemic muscle and joint pain and palpitations is outlined. Subsequently, the patient was admitted to the Department of Nephrology for the treatment of "multiple myeloma nephropathy pending investigation". The patient was diagnosed with "primary hyperparathyroidism and hypercalcemic crisis" using thyroid color ultrasound.

CONCLUSION

The intraoperative frozen section report considered the parathyroid tumor. Surgical tumor resection was promptly performed, and the diagnosis of PC was confirmed.

Evidence-based cutoffs for total and adjusted calcium: a major factor in detecting severe hypo- and hypercalcemia

OBJECTIVES

Severe hypo- and hypercalcemia are common and urgent treatment is recommended. Free calcium (fCa) is the gold standard but needs blood gas tests with challenging preanalytics. Total calcium (tCa) and calculated adjusted calcium (aCa) are readily available, but their interpretation is hampered by identical tCa and aCa cutoffs, laborious local aCa calculation and difficult comparability of calcium biomarkers.

METHODS

Laboratory results from University Medicine Leipzig were evaluated over a five-year period (236,274 patients). A local aCa equation was derived by linear least squares regression, the agreement between fCa, tCa and aCa assessed with Cohen's κ and decision thresholds derived by this indirect method.

RESULTS

The local aCa equation was created from data of 9,756 patients, each with one paired measurement of tCa, fCa and albumin. Derived aCa cutoffs (1.95/3.15 mmol/L) differ markedly from derived tCa cutoffs (1.6/2.9 mmol/L) and severe hypo- and hypercalcemia can be more accurately assessed by aCa (κ=0.489, 0.812) than by tCa (κ=0.445, 0.744). Comparing our approach to standard care (tCa, literature cutoff), a total 3,250 of 3,680 (88.3 %) misclassified measurements were correctly classified when using aCa with evidence-based cutoffs.

CONCLUSIONS

Optimized cutoffs for aCa and tCa hold great potential for improved patient care. Locally derived aCa equations differ mostly in the chosen mean normal calcium and provide minimal overall improvement, but entail a close examination of the used cutoffs before application.

Comparison of endoscopic versus focused parathyroidectomy in surgical management of single-gland primary hyperparathyroidism: a randomized clinical trial

BACKGROUND

Over recent years, various advanced minimally invasive techniques have been developed for parathyroidectomy, and there was a universal acceptance of these less invasive procedures by surgeons. This study is designed to compare overall outcomes between endoscopic versus focused, single gland parathyroidectomy using intraoperative rapid parathyroid hormone (ioPTH) changes under general anesthesia in primary hyperparathyroidism (PHPT) patients.

METHOD

In this randomized clinical trial, 96 patients diagnosed with PHPT were randomly assigned into two groups endoscopic and focused parathyroidectomy. Baseline clinical and demographical data were collected along with perioperative features. The success rate was evaluated based on ioPTH changes.

RESULTS

The ioPTH levels after five minutes in the endoscopic group were significantly lower than the focused group (P = 0.005). The success rate for endoscopic and the focused method was 95.3% and 77.1% during the first five minutes (P = 0.013) and 100% in both groups after ten minutes. A decrease in parathyroid hormone levels was significant in each group but not between each other. Postoperative calcium levels were significantly lower in the focused method (P = 0.042). The focused group also had a significantly shorter operation time than the endoscopic group (P < 0.001). Patient satisfaction with cosmetic outcome was significantly higher in the endoscopic group compared to the focused group.

CONCLUSION

The endoscopic technique was superior to the unilateral focused neck exploration parathyroidectomy in the management of single-gland PHPT. Influencing aspects included higher postoperative calcium levels, more rapid success achievement, and satisfactory cosmetic outcomes in the endoscopic group. However, patient selection and accurate adenoma localization are vital in this method.

Management of surgical diseases of Primary Hyperparathyroidism: indications of the United Italian Society of Endocrine Surgery (SIUEC)

A task force of the United Italian society of Endocrine Surgery (SIUEC) was commissioned to review the position statement on diagnostic, therapeutic and health‑care management protocol in parathyroid surgery published in 2014, at the light of new technologies, recent oncological concepts, and tailored approaches. The objective of this publication was to support surgeons with modern rational protocols of treatment that can be shared by health-care professionals, taking into account important clinical, healthcare and therapeutic aspects, as well as potential sequelae and complications. The task force consists of 12 members of the SIUEC highly trained and experienced in thyroid and parathyroid surgery. The main topics concern diagnostic test and localization studies, mode of admission and waiting time, therapeutic pathway (patient preparation for surgery, surgical treatment, postoperative management, management of major complications), hospital discharge and patient information, outpatient care and follow-up, outpatient initial management of patients with pHPT.

The Ca∗Cl/P Ratio: A Novel and More Appropriate Screening Tool for Normocalcaemic or Overt Primary Hyperparathyroidism

OBJECTIVE

The main purpose of this study was to explore the diagnostic performance of the Ca∗Cl/P ratio for primary hyperparathyroidism (PHPT), especially normocalcaemic PHPT (NPHPT), to assist health care providers in making reliable and rapid clinical identifications.

METHODS

From January 1, 2013, to March 31, 2023, 230 PHPT patients, including 65 with NPHPT and 230 sex- and age-matched controls, were enrolled in this retrospective study. Differences between hypercalcaemic PHPT (HPHPT) and NPHPT and between them and their respective controls were analyzed. The diagnostic accuracy of the Ca∗Cl/P ratio, Ca/P ratio, Cl/P ratio and albumin-corrected calcium was assessed by the area under the receiver operating characteristic curve.

RESULTS

Compared with corresponding controls, NPHPT and HPHPT patients both had significantly higher Ca ∗ Cl/P ratios (271.64 ± 51.74 vs 192.71 ± 26; 419.91 ± 139.11 vs 199.14 ± 36.75, P < .001). In the overall cohort, the ROC-AUC of the Ca∗Cl/P ratio (0.964, 95% CI = 0.943-0.979) for diagnosis of PHPT patients was superior to albumin-corrected calcium (0.959, 95% CI = 0.934-0.973), the Ca/P ratio (0.956, 95% CI = 0.934-0.973), and the Cl/P ratio (0.923, 95% CI = 0.895-0.946). A Ca ∗ Cl/P ratio above 239.17 mmol/L, with sensitivity (0.952), specificity (0.922), PPV (0.924), NPV (0.951) and accuracy (0.937), can distinguish PHPT patients from healthy individuals. Furthermore, the Ca ∗ Cl/P ratio yielded a sensitivity of 0.831, specificity of 0.938, PPV of 0.931, NPV of 0.847 and accuracy of 0.885 for NPHPT.

CONCLUSION

The Ca∗Cl/P ratio provides excellent diagnostic power for diagnosis of PHPT, especially NPHPT.

Primary Hyperparathyroidism With Brown Tumor of the Mandible Misdiagnosed as a Giant Cell Tumor: A Case Report

In this case study, we present an incidentally discovered giant cell granuloma, which, upon detailed investigation, led to an unexpected diagnosis. A 36-year-old woman exhibited a bone lesion in the right retromolar trigone area, initially suspected of being malignant. However, histopathological examination revealed a giant cell tumor of bone. Further biochemical profiling, including serum calcium, phosphorus, and parathyroid hormone (PTH) levels, showed elevated PTH and hypercalcemia, prompting consideration of primary hyperparathyroidism and the diagnosis of a brown tumor due to this condition. This case underscores the importance of considering brown tumors associated with primary hyperparathyroidism as a potential differential diagnosis in patients with lytic bone lesions.

Hypercalcemic Crisis Due to a Giant Intrathyroidal Parathyroid Adenoma, with Postsurgical Severe Hypocalcemia and Hungry Bone Syndrome: A Case Report

BACKGROUND

Parathyroid adenoma is the most common cause of hypercalcemia and rarely leads to a hypercalcemic crisis, which is an unusual endocrine emergency that requires timely surgical excision.

CASE PRESENTATION

A 67-year-old male was admitted to the ER of the Euroclinic Hospital, Athens, Greece, because of elevated calcium levels and a palpable right-sided neck mass, which were accompanied by symptoms of nausea, drowsiness, and weakness for six months that increased prior to our evaluation. A gradual creatinine elevation and decreasing mental state were observed as well. The initial laboratory investigation identified severely elevated serum calcium (3.6 mmol/L) levels consistent with a hypercalcemic crisis (HC) and parathyroid hormone PTH (47.6 pmol/L) due to primary hyperparathyroidism. Neck ultrasonography (USG) identified a large, well-shaped cystic mass in the right thyroid lobe. With a serum calcium concentration of 19.5 mg/dL and a PTH of 225.3 pmol/L, the patient underwent partial parathyroidectomy and total thyroidectomy, which decreased serum calcium and PTH to 2.5 mmol/L and 1.93 pmol/L, respectively. Histology revealed a giant intrathyroidal cystic parathyroid adenoma, which was responsible for the hypercalcemic crisis. Postoperatively, the patient developed severe biochemical and clinical hypocalcemia, with calcium concentrations as low as 1.65 mmol/L, consistent with hungry bone syndrome (HBS), which was treated with high doses of intravenous calcium gluconate and oral alfacalcidol, and a slow recovery of serum calcium. After discharge, parathyroid function recovered, and symptomatology resolved entirely in more than one month.

DISCUSSION/CONCLUSIONS

We present a case involving an exceptionally large intrathyroidal parathyroid adenoma that is characterized by clinical manifestations that mimic malignancy. The identification and treatment of such tumors is challenging and requires careful preoperative evaluation and postoperative care for the risk of hungry bone syndrome.

Sonographic Features of Atypical and Initially Missed Parathyroid Adenomas: Lessons Learned From a Single-Center Cohort

CONTEXT

Awareness of typical and atypical ultrasonographic (US) features of parathyroid adenomas (PAs) is crucial since US is the most widely used first-line imaging modality.

OBJECTIVE

The purpose of this study was to describe the atypical features of PAs on US and other possible factors leading to a false negative examination in a large single-center cohort.

MATERIALS AND METHODS

The US records of 457 PAs in 445 patients with biochemically proven primary hyperparathyroidism (PHPT) were evaluated in a prospectively maintained database. Atypical size, composition, shape, echogenicity, location, and vascular pattern on US were noted. For patients who previously had at least one negative US examination in referring centers, the main possible reason was defined accordingly.

RESULTS

The study group included 359 female and 86 male patients with PHPT. Typical sonographic features were observed in 231 PAs (51%), whereas 226 (49%) had at least one atypical US feature. The most common atypical features were atypical size (29%), followed by atypical echogenicity (19%), shape (8%), location (7%), and composition (7%), respectively. There were 122 initially missed PAs in all groups. The most frequent main atypical US features leading to false negative examinations were atypical size (22.1%) and atypical location (18.8%). Inexperience was third most common reason (16.3%) for false negative US examinations.

CONCLUSIONS

Almost half of PAs have at least one atypical feature on US. Awareness of the high prevalence of atypical US features could increase the accuracy of US examination and potentially decrease demand for more expensive second-line imaging modalities.

[Diagnosis and management of primary hyperparathyroidism during pregnancy: A systematic review and a longitudinal case study]

OBJECTIVE

There is no specific recommendation for management in pregnant women: the aim of this review, based on a clinical case study, is to clarify its development, complications, risk factor and treatment.

METHODS

A review of the literature was performed by consulting the Pubmed, Cochrane Library, and Science Direct databases.

RESULTS

Primary hyperparathyroidism is defined as excessive production of parathyroid hormone resulting in hypercalcemia. The prevalence of primary hyperparathyroidism during pregnancy is not known. Indeed, the symptomatology, related to hypercalcemia, is not very specific and easily confused with the clinical manifestations of pregnancy. The physiological changes specific to the pregnant state frequently lead to a slight hypocalcemia which may complicate the diagnosis of primary hyperparathyroidism. Primary hyperparathyroidism results from a parathyroid adenoma in the majority of cases and is detected by ultrasound during pregnancy. Primary hyperparathyroidism in pregnancy causes significant risks to both mother and fetus. The maternal complication rate is 14-67%, however, the most serious complication is hypercalcemic crisis, which requires increased surveillance in the postpartum period. Obstetrical complications are also induced by primary hyperparathyroidism, such as acute polyhydramnios, or intrauterine growth retardation. The fetal complication rate can reach 45-80% of cases with neonatal hypocalcemia as the main complication. If medical treatment is based on hyperhydration, only surgical treatment is curative.

CONCLUSION

Surgery should be proposed to symptomatic patients or those with high blood calcium levels, discussed in interdisciplinary committee and should be organized ideally in the second trimester to avoid maternal and fetal complications.

Femoral Neck Fracture in a Pediatric Patient with Primary Hyperparathyroidism

Case

A previously healthy 11-year-old girl underwent expedited surgical fixation of a femoral neck fracture sustained while jump-roping. After further work up, she was diagnosed with primary hyperparathyroidism. Parathyroidectomy of a hypertrophic adenoma proved curative. Now, five months post left hip surgery, the patient is pain-free and walks without a limp.

Conclusion

We describe the first published case of primary hyperparathyroidism presenting as a pathologic hip fracture in a child. Although presentation with a fracture is exceedingly rare, bone pain is a frequent complaint of pediatric hyperparathyroidism. Orthopedic surgeons may find themselves the front-line caregivers for the condition.

Application of calcium-to-phosphorus (Ca/P) ratio in the diagnosis of pseudohypoparathyroidism: another piece in the puzzle of diagnosis of Ca-P metabolism disorders

Objective

The serum calcium (Ca)-to-phosphorus (P) ratio has been proposed to identify patients with primary hyperparathyroidism and chronic hypoparathyroidism (HPT), but it has never been tested in pseudohypoparathyroidism (PHP). The aim of this study was to test the performance of Ca/P ratio in PHP diagnosis compared with that in healthy subjects and patients with HPT for differential diagnosis.

Design

A retrospective, cross-sectional, and observational study was carried out.

Methods

Serum Ca, P, creatinine, parathyroid hormone (PTH), and albumin were collected. Ca and P were expressed in mmol/L. Ca/P diagnostic performance was evaluated by receiver operating characteristic curve, sensitivity, specificity, and accuracy.

Results

A total of 60 patients with PHP, 60 patients with HPT, and 120 controls were enrolled. The Ca/P ratio was lower in patients with PHP and HPT than that in controls (p < 0.0001). The cutoff of 1.78 (2.32 if Ca and P measured in mg/dL) for Ca/P ratio could identify patients with PHP and HPT among the entire cohort (sensitivity and specificity of 76%). No valid cutoff of Ca/P was found to distinguish patients with PHP from patients with HPT; in this case, PTH above 53.0 ng/dL identified patients with PHP (sensitivity and specificity of 100%). The index (Ca/P × PTH) above 116 ng/L recognized patients with PHP from controls (sensitivity of 84.7% and specificity of 87.4%), whereas (Ca/P × PTH) below 34 ng/L recognized patients with HPT from controls (sensitivity of 88.9% and specificity of 90.8%).

Conclusions

The Ca/P ratio below 1.78 (2.32 CU) is highly accurate to identify patients with PHP and HPT, although it is not reliable to differentiate these two conditions. The index (Ca/P × PTH) is excellent to specifically recognize PHP or HPT from healthy subjects.

Clinical Decision Support systems: A step forward in establishing the clinical laboratory as a decision maker hubA CDS system protocol implementation in the clinical laboratory

Background

New tools for health information technology have been developed in recent times, such as Clinical Decision Support (CDS) systems, which are any digital solutions designed to help healthcare professionals when making clinical decisions. The study aimed to show how we have adopted a CDS system in the San Juan de Alicante Clinical Laboratory and facilitate the implementation of our protocol in other clinical laboratories. We have user experience and the motivation to improve healthcare tools. The improvement, measurement, and monitoring of interventions and laboratory tests has been our motto for years.

Materials and methods

A descriptive research was conducted. All stages in the design of the project are as follows: 1. Set up a multidisciplinary workgroup. 2. Review patients' data. 3. Identify relevant data from main sources. 4. Design the likely outcomes. 5. Define a complete integration scenario. 6. Monitor and track the impact. To set up this protocol, two new software systems were implemented in our laboratory: AlinIQ CDS v8.2 as Rule Engine, and AlinIQ AIP Integrated Platform v1.6 as Business Intelligence (BI) tool.

Results

Our protocol shows the workflow and actions that can be done with a CDS system and also how it could be integrated with other monitoring systems, as well as some examples of KPIs and their outcomes.

Conclusions

CDS could be a great strategic asset for clinical laboratories to improve the integration of care, optimize the use of laboratory tests, and add more clinical value to physicians in the interpretation of results.

Large Water-Clear-Cell Parathyroid Adenoma: A Report of a Rare Case

Water-clear-cell parathyroid adenomas are extremely rare tumors characterized by cells that contain clear, foamy cytoplasm. Here we report a case of a large water-clear-cell parathyroid adenoma in a 70-year-old male. The patient was presented to an outside hospital with severe abdominal pain and supporting CT imaging confirming a small bowel obstruction. Initial laboratory studies revealed hypercalcemia and elevated parathyroid hormone levels. Subsequent ultrasound imaging revealed a 2.7 × 2.1 cm neck mass suspicious for a parathyroid adenoma. A parathyroidectomy was performed, and microscopic evaluation revealed an expansile proliferation of cells with characteristic water-clear cell features. Although rare, water-clear-cell parathyroid adenomas are clinically indistinguishable from more common subtypes and should be considered in the differential diagnosis of an anterior neck mass.

The Impact of Moderate Hypophosphatemia on the Clinical Management of Primary Hyperparathyroidism

Background and objective The impact of moderate hypophosphatemia (hypoP) on primary hyperparathyroidism (PHPT) and its use as an independent surgical criterion has not been adequately evaluated in the literature. In light of this, we conducted this study to address the scarcity of data on this topic. Methods We conducted a retrospective evaluation of data related to 164 (133 females and 31 males) patients with PHPT who met the criteria for inclusion in the study. HypoP, which is indicated by phosphorus (P) levels lower than 2.5 mg/dL, was found in 78 (47.5%) patients, and moderate hypoP (1-1.99 mg/dL) was found in 25 patients (15.2%). Results PHPT severity was worse in hypoP patients than non-hypoP patients, as evidenced by higher levels of mean serum calcium (12.9 ±1.0 mg/dL vs. 11.1 ±0.3 mg/dL respectively, p<0.001), parathormone (PTH) [median (interquartile range, IQR): 455.3 (455.3) ng/L vs. 124.0 (84.0) ng/L respectively, p<0.001] and mean 24-hour urinary calcium (414.6 ±168.5 mg/day vs. 291.5 ±161.4 mg/day respectively, p=0.026) as well as lower levels of mean BMI (25.6 ±3.9 kg/m2 vs. 29.0 ±4.0 kg/m2 respectively, p=0.18) and mean 25-hydroxy vitamin D3 (13.8 ±7.3 µg/L vs. 18.2 ±7.8 µg/L respectively, p=0.001). Among the whole study population as well as among patients with Ca levels <1.0 mg/dL according to the upper limit of normal, P level was determined to be an independent factor affecting the indication for surgical treatment [β: -1.96,p=0.038, odds ratio (OR): 0.14, 95% confidence interval (CI): 0.02-0.89 and β: -2.3, p=0.034, OR: 0.10, 95% CI: 0.12-0.84 respectively]. Conclusion We found a strong correlation between moderate hypoP and the severity of the biochemical manifestations of PHPT. In asymptomatic PHPT patients, moderate hypoP was predictive of surgical indication, independent of age and level of hypercalcemia.

A Rare Case of Hyperfunctioning Lipoadenoma Presenting as a Cystic Pararthyroid Lesion

A 58-year-old woman visited the hospital complaining of fatigue and indigestion lasting for more than 3 months. She had no medical history other than taking a calcium plus vitamin D supplement for osteopenia. The initial blood test showed a high calcium level of 14.0 mg/dL. Additional tests were performed to differentially diagnose hypercalcemia. The blood test results were as follows: serum parathyroid hormone (PTH)=247.0 pg/mL, PTH-related peptide <1.0 pg/mL, phosphorous=2.6 mg/dL, 25-hydroxy-vitamin D=14.5 pg/mL, creatinine=1.09 mg/dL, and 24 hr urine calcium=215 mg/dL. A 4.5 cm sized cystic lesion on the intra-thyroidal space was confirmed on neck sonography and 4-dimensional parathyroid computed tomography, but technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy showed equivocal results. After removal of the cystic lesion, serum calcium and PTH were normalized, and parathyroid lipoadenoma was confirmed in the postoperative pathology. Clinical features of parathyroid lipoadenoma are known to be similar to common parathyroid adenoma, but imaging studies often report negative findings. Therefore, it is necessary to better understand this rare disease for the differential diagnosis. For the final diagnosis and treatment of this disease, parathyroidectomy with intraoperative PTH measurement may be required.

Evaluation of factors predicting postoperative recurrence and metastasis of parathyroid cancer: a single-center study

PURPOSE

The purpose of this study was to examine the postoperative clinical course of parathyroid carcinoma to determine factors that predict postoperative recurrence and distant metastasis.

METHODS

In this retrospective study, we included 38 patients with parathyroid carcinoma who received surgical intervention at Itoh Hospital between 1979 and 2020. Clinicopathologic characteristics (age, sex, intact PTH, serum Ca level, operation type, parathyroid weight, parathyroid size, histopathologic findings: vascular invasion, capsular invasion, necrosis, histological type, and Ki-67 staining) were used. The median follow-up observation period was 63.7 months.

RESULTS

Postoperatively, 5 patients (13.2%) developed distant metastasis or had localized recurrence, and 3 patients died (7.9%). The results of the univariate analysis revealed three factors affecting distant metastasis and recurrence, which were Ki-67 (p = 0.0041), the presence or absence of necrosis (p = 0.0163), and tumor weight (p = 00,189). Using the cutoff values obtained by ROC analysis, which were 4.1 for Ki-67 (sensitivity of 80% and specificity of 96.9%) and 4890 mg for tumor weight (sensitivity of 100% and specificity of 60.9%), we calculated the cumulative incidence of recurrence and distant metastasis by the three factors retained. We found that the presence of the three factors was associated with a high possibility of distant metastasis or recurrence during the 5-year follow-up period.

CONCLUSIONS

Three factors, Ki-67, necrosis, and tumor weight in parathyroid carcinoma, may predict outcomes of postoperative recurrence and distant metastasis.

Giant Ectopic Parathyroid Adenoma Arising in the Posterior Mediastinum. Report of Case and a Review

We present a case of a greatly enlarged giant ectopic parathyroid adenoma that weighed 43 grams, which was located in the posterior mediastinum of a 74-year-old man. The patient presented with generalized weakness and decreased level of consciousness. He was found to have elevated level of serum calcium (19.9 mg/dl), and a subsequent assay of parathyroid hormone (PTH) was greatly elevated (2234 pg/ml). We report the course of management and outcome of the patient and present a review of the literature on giant ectopic parathyroid adenomas in the posterior mediastinum.

Single-Center Experience of Parathyroidectomy Using Intraoperative Parathyroid Hormone Monitoring

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

Analysis of the successful clinical treatment of 140 patients with parathyroid adenoma: A retrospective study

BACKGROUND

Parathyroid adenoma (PA) sometimes recurs after surgery, how to improve the surgical success rate of PA is the key to the treatment of this disease.

AIM

To investigate the clinical features, diagnosis, and surgical treatment of patients with PA.

METHODS

Patients who were pathologically confirmed with PA and had undergone surgery for the first time between January 2010 and December 2017 at the Beijing Shijitan Hospital affiliated to Capital Medical University were included in the study. The clinical features, localization diagnosis, and surgical treatment of these patients were analyzed.

RESULTS

Of the 140 patients, 32 were male and 108 were female; 132 cases had one adenoma, and 8 had two adenomas. In addition, 114 cases had clinical symptoms, among which 51, 28, 23, 8, and 4 had urinary system, skeletal system, digestive system, neuromuscular system, and neuropsychiatric symptoms, respectively, while 26 cases had no obvious symptoms. The median level of preoperative parathyroid hormone (PTH) was 201.0 pg/mL. The positive detection rate of technetium-99m sestamibi (Tc-99m MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT), ultrasound examination, and the combined use of Tc-99m MIBI SPECT/CT and ultrasound examination was 92.9%, 85.5%, and 96.4%, respectively. Open surgery was performed in all patients, and PTH was monitored during surgery. The success rate of surgery was 98.6%. After surgery, 21 cases developed hypocalcemia, 1 case developed temporary hoarseness, and 19 cases had transient hypoparathyroidism but there was no permanent hypoparathyroidism, postoperative hemorrhage, or hematoma in the surgical area.

CONCLUSION

For patients with clinically unexplained skeletal system, urinary system, and neuropsychiatric symptoms, the possibility of PA should be considered. Imaging examinations such as ultrasound and Tc-99m MIBI SPECT/CT could be integrated before surgery to obtain accurate localization diagnosis. Precise preoperative localization, intraoperative PTH monitoring, and delicate surgery to protect the integrity of the PA capsule ensure a minimally invasive and successful surgery.

Evolution of intra-operative parathyroid hormone and its application in parathyroid surgery

The history and evolution of parathyroid hormone is a true testament to inter-disciplinary collaboration among anatomists, biochemists and surgeons. The parathyroid glands were the last endocrine glands to be discovered in the mid-1800s. Over the next century, progress in the evaluation of primary hyperparathyroidism, the identification of parathyroid hormone (PTH) and its application for use in the field of parathyroid surgery have led to a significant improvement in surgical cure rates, accompanied by a shift toward minimally invasive surgical options. This chapter provides a historical lens through which we can view these relatively recent advancements, as well as the current role of parathyroid hormone, both with regards to pre-operative localization and intra-operative detection of abnormal glands. Furthermore, we discuss the importance of parathyroid hormone in the management of complex multiglandular disease and reoperative cases, as well as the significance of persistently elevated PTH levels post-parathyroidectomy.

Preoperative inflammatory markers for predicting parathyroid carcinoma

OBJECTIVE

Parathyroid carcinoma is a rare tumor among parathyroid tumors. Aspiration cytology and needle biopsy are generally not recommended for diagnostic purposes because they cause dissemination. Therefore, it is commonly diagnosed by postoperative histopathological examination. In this study, we investigated whether preoperative inflammatory markers can be used as predictors of cancer in patients with primary hyperparathyroidism.

DESIGN

This was a retrospective study.

METHODS

Thirty-six cases of parathyroid carcinoma and 50 cases of parathyroid adenoma (PA) operated with the diagnosis of primary hyperparathyroidism and confirmed histopathologically at Ito Hospital were included in this study. Preoperative clinical characteristics and inflammatory markers (neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and lymphocyte-to-monocyte ratio (LMR)) were compared and their values in preoperative prediction were evaluated and analyzed.

RESULTS

Preoperative intact-parathyroid hormone (P = 0.0003), serum calcium (P = 0.0048), and tumor diameter (P = 0.0002) were significantly higher in parathyroid carcinoma than in PA. LMR showed a significant decrease in parathyroid carcinoma (P = 0.0062). In multivariate analysis, LMR and tumor length diameter were independent predictors. In the receiver operating characteristics analysis, the cut-off values for LMR and tumor length diameter were 4.85 and 28.0 mm, respectively, for parathyroid cancer prediction. When the two extracted factors were stratified by the number of factors held, the predictive ability improved as the number of factors increased.

CONCLUSION

In the preoperative evaluation, a combination of tumor length diameter of more than 28 mm and LMR of less than 4.85 was considered to have a high probability of cancer.

Implications of regulator of G-protein signaling 5 expression in the pathogenesis of primary and secondary hyperparathyroidism

OBJECTIVE

To study the protein and mRNA expressions of regulator of G-protein signaling 5 (RGS5) in the pathogenesis of hyperparathyroidism.

METHODS

The expression of RGS5 protein in 20 primary hyperparathyroidism (PHPT), 31 secondary hyperparathyroidism (SHPT), and 20 control cases were studied by immunohistochemistry (IHC). The expression of RGS5 mRNA in 15 PHPT, 102 SHPT, and 7 normal parathyroid tissue were measured by quantitative real-time PCR (qRT-PCR) method.

RESULTS

The expressions of RGS5 in PHPT tissues were significantly higher than that in SHPT and normal parathyroid tissues (P < 0.05). While the differences in RGS5 protein expressions between SHPT and respective control samples were not statistically significant (P > 0.05). Likewise, the RGS5 mRNA expression in PHPT was significantly higher than that in SHPT (P < 0.05) and normal parathyroid (P < 0.05) samples. In a similar line, the differences in RGS5 gene expressions between SHPT and control tissues were not statistically significant (P > 0.05).

CONCLUSIONS

The characteristic RGS5 protein and mRNA levels in hyperparathyroidism might be helpful in discovering the pathomechanism of hyperparathyroidism and novel therapeutic targets as well.

Case Report: Primary Hyperparathyroidism due to Posterior Mediastinal Parathyroid Adenoma With One-Year Follow-Up

Ectopic parathyroid adenoma, though rare, is one of the causes of persistent hyperparathyroidism and recurrence of hyperparathyroidism. Ectopic parathyroid glands can be seen in thymus, thyroid, and mediastinum. However, ectopic parathyroid adenoma occurred in the posterior superior mediastinum is extremely rare. Here, we report a case of primary hyperparathyroidism caused by ectopic parathyroid adenoma located in the posterior superior mediastinum. Serum parathyroid hormone, calcium, and vitamin D levels of the patient was followed up for one year.

Diagnostic significance of parafibromin expression in parathyroid carcinoma

Parathyroid carcinomas are difficult to distinguish from adenomas according to the current diagnostic criteria. The judgment of local infiltration is subjective and inconsistent. Existing studies have found that the CDC73 gene encoding parafibromin is related to the occurrence of parathyroid carcinomas. This study is aimed at investigating whether immunohistochemistry of parafibromin is helpful in distinguishing malignant from benign parathyroid tumours. A total of 53 patients with parathyroid carcinoma from Peking Union Medical College Hospital were included. Metastasis was found in 17/53 of patients. In addition, another 53 patients with parathyroid adenomas were included as controls. Appropriate sections were stained with an immunohistochemical autostainer. Three senior pathologists evaluated the sections and analysed their clinicopathological features independently. The loss of parafibromin expression only occurred in malignant tumours, including all carcinomas with metastasis (17/17) and 14/36 of carcinomas with only local infiltration. All staining results of adenomas (53/53) were positive. Considering invasion as the gold standard of malignancy, the sensitivity of parafibromin staining is 58%, and the specificity is 100%. If the gold standard is changed to metastasis, the sensitivity becomes 100%, and the specificity becomes 84%. By analysing clinicopathological features with metastasis and parafibromin staining, it is found that local-infiltrative carcinomas with positive staining results have better biological behaviours than carcinomas lack of parafibromin expression. Parafibromin staining is highly recommended as an auxiliary method in the diagnosis of parathyroid carcinoma.

Relationship between patients' characteristics and efficacy of calcimimetics for primary hyperparathyroidism in the elderly

Calcimimetic treatment has been reported to be effective for primary hyperparathyroidism (PHPT). Nine elderly PHPT patients who had been treated with calcimimetics were retrospectively analyzed. It was found that calcimimetics can reduce elevated serum calcium levels in elderly PHPT patients with low femoral DEXA %YAM and low urinary cAMP levels.

Multiple electrolyte disturbances as the presenting feature of multiple endocrine neoplasia type 1 (MEN-1)

Summary

A 49-year-old teacher presented to his general physician with lethargy and lower limb weakness. He had noticed polydipsia, polyuria, and had experienced weight loss, albeit with an increase in central adiposity. He had no concomitant illnesses and took no regular medications. He had hypercalcaemia (adjusted calcium: 3.34 mmol/L) with hyperparathyroidism (parathyroid hormone: 356 ng/L) and hypokalaemia (K: 2.7 mmol/L) and was admitted for i.v. potassium replacement. A contrast-enhanced CT chest/abdomen/pelvis scan revealed a well-encapsulated anterior mediastinal mass measuring 17 × 11 cm with central necrosis, compressing rather than invading adjacent structures. A neck ultrasound revealed a 2 cm right inferior parathyroid lesion. On review of CT imaging, the adrenals appeared normal, but a pancreatic lesion was noted adjacent to the uncinate process. His serum cortisol was 2612 nmol/L, and adrenocorticotrophic hormone was elevated at 67 ng/L, followed by inadequate cortisol suppression to 575 nmol/L from an overnight dexamethasone suppression test. His pituitary MRI was normal, with unremarkable remaining anterior pituitary biochemistry. His admission was further complicated by increased urine output to 10 L/24 h and despite three precipitating factors for the development of diabetes insipidus including hypercalcaemia, hypokalaemia, and hypercortisolaemia, due to academic interest, a water deprivation test was conducted. An 18flurodeoxyglucose-PET (FDG-PET) scan demonstrated high avidity of the mediastinal mass with additionally active bilateral superior mediastinal nodes. The pancreatic lesion was not FDG avid. On 68Ga DOTATE-PET scan, the mediastinal mass was moderately avid, and the 32 mm pancreatic uncinate process mass showed significant uptake. Genetic testing confirmed multiple endocrine neoplasia type 1.

Learning points

In young patients presenting with primary hyperparathyroidism, clinicians should be alerted to the possibility of other underlying endocrinopathies. In patients with multiple endocrine neoplasia type 1 (MEN-1) and ectopic adrenocorticotrophic hormone syndrome (EAS), clinicians should be alerted to the possibility of this originating from a neoplasm above or below the diaphragm. Although relatively rare compared with sporadic cases, thymic carcinoids secondary to MEN-1 may also be associated with EAS. Electrolyte derangement, in particular hypokalaemia and hypercalcaemia, can precipitate mild nephrogenic diabetes insipidus.

Serum Phosphate: A Neglected Test in the Clinical Management of Primary Hyperparathyroidism

BACKGROUND

Although the inverse correlation between serum PTH and phosphate (P) levels in patients with primary hyperparathyroidism (PHPT) is well known, the relationship between P levels and the clinical picture of the disease has not been well investigated. This was thus the aim of this paper.

PATIENTS

A total of 472 consecutive patients with PHPT attending our center were retrospectively evaluated at diagnosis.

RESULTS

P levels lower than 2.5 mg/dL (HypoP) were found in 198/472 patients (41.9%). HypoP was mild (2-2.5 mg/dL), moderate (1-1.9 mg/dL), and severe (<1 mg/dL) in 168 (84.9%), 30 (15.1%), and 0 cases, respectively. P levels were lower in males than females. Patients with more severe bone density impairment at the radial (but not the vertebral or femoral) site had P levels significantly lower than other patients. PHPT severity was worse in HypoP patients, both clinically (higher prevalence of renal stones, but not of osteoporosis) and biochemically (higher serum calcium and PTH levels). All patients in the moderate HypoP group were either symptomatic or asymptomatic reaching surgical indication according to the latest guidelines.

CONCLUSIONS

We observed a relationship between P levels and biochemical and clinical features of PHPT severity. In asymptomatic PHPT patients, even moderate HypoP is predictive of surgical indication, regardless of age and hypercalcemia severity.

Persistent hyperparathyroidism secondary to ectopic parathyroid adenoma in lung: Case report

Primary hyperparathyroidism (PHPT) is the most prevalent cause of hypercalcemia, affecting 0.3% of the population. The only curative procedure is parathyroidectomy. Persistent PHPT occurs in 4.7 percent of patients, even in the most skilled hands. Ectopic adenomas are challenging to localize before and during surgery and frequently result in persistent PHPT. We presented a case with persistent PHPT due to lung parathyroid adenoma that was successfully resected with video-assisted thoracoscopic surgery. A 55-year-old female patient was admitted to our endocrinology clinic with persistent PHPT after four neck explorations over 16 years. The last ⁹⁹m Tc-MIBI scintigraphy with SPECT showed nothing suggestive of parathyroid adenoma, neither in the neck nor the mediastinum, but a solitary nodule as an incidental finding was reported in the lower lobe of the right lung, which was highly probable for a parathyroid adenoma in a fluorodeoxyglucose PET scan. Pathological examination ruled out parathyromatosis and lung malignancy; despite its location outside the anticipated embryonic pathway, pathology revealed the presence of an ectopic parathyroid adenoma. After the surgery, serum parathyroid hormone and calcium levels decreased, and hypoparathyroidism was corrected with calcium carbonate and calcitriol.

Proximal Myopathy With Hypercalcemic Crisis and Papillary Thyroid Carcinoma in a 38-Year-Old Female

Although proximal myopathy is a well-known manifestation of primary hyperparathyroidism (PHP), it is usually not the first one. Here, we present the case of a 38-year-old female who presented to the neurology outpatient department with proximal myopathy as the presenting feature of PHP along with a hypercalcemic crisis. Her serum calcium and intact parathyroid hormone levels were very high. Her symptoms and calcium levels improved with adequate hydration and bisphosphonate therapy. Ultrasonography of the thyroid and parathyroid glands and Tc99m sestamibi single-photon emission computed tomography-computed tomography of the parathyroid glands suggested adenoma or carcinoma of the parathyroid gland on the right side with another irregular right-sided thyroid nodule. Electromyography showed low-amplitude polyphasic potentials suggestive of myopathy. Subsequently, the patient underwent surgical resection of both the right parathyroid glands and the thyroid nodule. Histopathology report was suggestive of parathyroid adenoma and papillary thyroid carcinoma. Hypercalcemic crisis is a rare clinical scenario, which needs prompt diagnosis and treatment. Otherwise, the condition may have a fatal outcome. Due to its diverse presentation, physicians should be aware of this condition. Moreover, we need to be cautious in treating a patient having hyperparathyroidism with thyroid nodule due to possible concomitant thyroid malignancy.

Analyzing Genetic Differences Between Sporadic Primary and Secondary/Tertiary Hyperparathyroidism by Targeted Next-Generation Panel Sequencing

Secondary hyperparathyroidism (SHPT) is characterized by excessive serum parathyroid hormone levels in response to decreasing kidney function, and tertiary hyperparathyroidism (THPT) is often the result of a long-standing SHPT. To date, several genes have been associated with the pathogenesis of primary hyperparathyroidism (PHPT). However, the molecular genetic mechanisms of uremic hyperparathyroidism (HPT) remain uncharacterized. To elucidate the differences in genetic alterations between PHPT and SHPT/THPT, the targeted next-generation sequencing of genes associated with HPT was performed using DNA extracted from parathyroid tissues. As a result, 26 variants in 19 PHPT or SHPT/THPT appeared as candidate pathogenic mutations, which corresponded to 9 (35%) nonsense, 8 (31%) frameshift, 6 (23%) missense, and 3 (11%) splice site mutations. The MEN1 (23%, 6/26), ASXL3 (15%, 4/26), EZH2 (12%, 3/26), and MTOR (8%, 2/26) genes were frequently mutated. Sixteen of 25 patients with PHPT (64%) had one or more mutations, whereas 3 (21%) of 21 patients with SHPT/THPT had only 1 mutation (p = 0.001). Sixteen of 28 patients (57%) with parathyroid adenoma (PA) had one or more mutations, whereas 3 of 18 patients (17%) with parathyroid hyperplasia (PH) had just one mutation (p = 0.003). Known driver mutations associated with parathyroid tumorigenesis such as CCND1/PRAD1, CDC73/HRPT2, and MEN1 were identified only in PA (44%, 7/16 with mutations). Our results suggest that molecular genetic abnormalities in SHPT/THPT are distinct from those in PHPT. These findings may help in analyzing the molecular pathogenesis underlying uremic HPT development.

Changes in clinical patterns of Chinese patients with primary hyperparathyroidism in the past 12 years: a single-center experience

The clinical presentation of primary hyperparathyroidism (PHPT) differs between patients from developed and developing countries. In China, the clinical pattern has changed over the past few decades. Our aim was to elucidate general changes in the clinical characteristics of PHPT from 2010 to 2021. We enrolled 343 patients with PHPT at the Qilu Hospital of Shandong University, Jinan, China, from January 2010 to May 2021, including both surgical and non-surgical patients. Patients were divided into two subgroups, 2010-2016 (group A, n = 152) and 2017-2021 (group B, n = 191), based on the time span. We compared clinical manifestations and laboratory result data between these two groups. The mean patient age was 52.59 ± 13.55 years, and the male-to-female ratio was 1:2.54. Of the 343 patients, 183 (53.35%) had symptomatic PHPT; bone pain, urolithiasis, and fatigue were the most common symptoms. Post-operative pathology showed that 96.20% of the patients had parathyroid adenoma, whereas 2.41% had parathyroid carcinoma. Great changes occurred between 2010 and 2021; the percentage of patients with asymptomatic PHPT (aPHPT) increased from 36.18% in group A to 54.97% in group B. Moreover, patients in group B showed significantly lower serum calcium, alkaline phosphatase, parathyroid hormone, and urinary phosphate levels but higher serum 25-hydroxyvitamin D levels than those in group A. Clinical presentations in group B were also milder. In conclusion, the clinical characteristics of Chinese PHPT patients changed dramatically from 2010 to 2021, with asymptomatic PHPT (aPHPT becoming the predominant type over the last 3 years.

Diagnostic performance of the calcium/phosphate ratio for primary hyperparathyroidism in southwest China

BACKGROUND

The diagnosis of primary hyperparathyroidism (PHPT) remains a challenge because of increased asymptomatic PHPT or patients with normocalcaemic PHPT (NPHPT). In addition, some primary hospitals in China have no equipment to measure parathyroid hormone (PTH) levels. Therefore, an additional, simple, and inexpensive laboratory biochemical marker is urgently needed. The calcium/phosphate (Ca/P) ratio and chloride/phosphate (Cl/P) ratio have been proposed as suitable tools to diagnose PHPT in Europe; however, the Ca/P ratio has never been tested in China. We aimed to conduct a confirmatory study to explore the diagnostic performance of the Ca/P ratio for PHPT in China.

METHODS

From January 2015 to December 2020, a total of 155 patients who underwent parathyroidectomy (143 PHPT patients and 12 NPHPT patients) and 153 controls were enrolled in this single-center , retrospective study. Serum calcium, phosphate, parathyroid hormone, 25-hydroxyvitamin vitamin D (25(OH) vitamin D), chloride, alanine transaminase (ALT), aspartate aminotransaminase (AST), estimated glomerular filtration rate (eGFR), and creatinine levels were recorded for all the study participants. Pairwise comparisons were made between groups, and the diagnostic performance of the Ca/P ratio was determined using receiver-operating characteristic (ROC) analysis.

RESULTS

Patients with PHPT had a higher Ca/P ratio than controls (P < 0.001). A Ca/P ratio above 2.94 with a sensitivity of 95.5% and specificity of 98.7% can distinguish PHPT patients from healthy individuals. This index was positively correlated with the PTH level (r = 0.875, P < 0.001).

CONCLUSION

The Ca/P ratio is an ideal and inexpensive indicator for diagnosing PHPT in China when using a cut-off value of 2.94.

Parathyroid Surgery: What Radiologists Need to Know

Surgical intervention remains the mainstay of treatment of hyperparathyroidism and provides the highest chance at cure. After the disease is confirmed by biochemical testing, surgeons must use a combination of patient clinical history and radiographic imaging to determine the most appropriate surgical strategy. Through either minimally invasive parathyroidectomy or bilateral cervical exploration, surgeons provide high rates of cure for hyperparathyroidism with low rates of persistence or recurrence.

A Tool to Locate Parathyroid Glands Using Dynamic Optical Contrast Imaging

OBJECTIVES/HYPOTHESIS

Identification of parathyroid glands and adjacent tissues intraoperatively can be quite challenging because of their small size, variable locations, and indistinct external features. The objective of this study is to test the efficacy of the dynamic optical contrast imaging (DOCI) technique as a tool in specifically differentiating parathyroid tissue and adjacent structures, facilitating efficient and reliable tissue differentiation.

STUDY DESIGN

Prospective study.

METHODS

Both animal and human tissues were included in this study. Fresh specimens were imaged with DOCI and subsequently processed for hematoxylin and eosin (H&E) stain. The DOCI images were analyzed and compared to the H&E results as ground truth.

RESULTS

In both animal and human experiments, significant DOCI contrast was observed between parathyroid glands and adjacent tissue of all types. Region of interest analysis revealed most distinct DOCI values for each tissue when using 494 and 572 nm-specific band pass filter for signal detection (P < .005 for porcine tissues, and P = .02 for human specimens). Linear discriminant classifier for tissue type prediction based on DOCI also matched the underlying histology.

CONCLUSIONS

We demonstrate that the DOCI technique reliably facilitates specific parathyroid gland localization. The DOCI technique constitutes important groundwork for in vivo precision endocrine surgery.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Metabolic Bone Diseases in the Pediatric Population

Bone plays an important role in regulating mineral balance in response to physiologic needs. In addition, bone is subject to a continuous remodeling process to maintain healthy bone mass and growth. Metabolic bone diseases are a heterogeneous group of diseases caused by abnormalities of bone mass, mineral structure homeostasis, bone turnover, or bone growth. In pediatrics, several significant advances have been made in recent years in the diagnosis of metabolic bone diseases (e.g., osteogenesis imperfecta, hyperparathyroidism, rickets, renal osteodystrophy, pediatric osteoporosis, and osteopetrosis). Imaging is fundamental in the diagnosis of these pathologies.

The clinical laboratory: a decision maker hub

OBJECTIVES

We aimed to share a new laboratory model based on laboratory knowledge, meaningful use of information technology, and partnership with clinicians, to lead the appropriate use of laboratory testing and clinical decision making in the diagnosis of as-yet-undiagnosed disease. More specifically, we evaluate the role of eight different opportunistic interventions to diagnose certain asymptomatic disorders, by means of the automatic registration of appropriate laboratory testing according to different scenarios.

METHODS

This is a retrospective longitudinal study to evaluate the impact of laboratory interventions on the diagnosis of different diseases and on patient care, including data from January 2012 to September 2020.

RESULTS

Overall, the above strategies have so far identified 2063 patients with clinically relevant as-yet-undiagnosed disorders who would have otherwise remained occult, such as for instance, primary hyperparathyroidism, diabetes, and hypomagnesemia.

CONCLUSIONS

We are facing a new laboratory model, a leading laboratory rather than a passive traditional laboratory, not just to intervene in clinical decision-making, but to make the clinical decision, through the identification of patients with occult disease.

Remission of Primary Hyperparathyroidism Following Fine-Needle Aspiration Biopsy: A Case Report and Review of the Literature

Background

Spontaneous or fine-needle aspiration biopsy (FNAB)-induced remission of primary hyperparathyroidism (PHPT) is an extremely rare and generally transient phenomenon.

Methods

A 40-year-old woman with a history of recurrent kidney stones was diagnosed with PHPT (serum calcium, 14.2 mg/dL; parathyroid hormone [PTH], 380 pg/mL). Ultrasonography and scintigraphy findings were consistent with a left enlarged parathyroid. Ultrasound-guided-FNAB cytology of the lesion did not confirm a parathyroid nature. However, levels of PTH within the needle-washing fluid were elevated.

Results

After few days, there was evidence of biochemical remission of the hypercalcemia (calcium, 8.1 mg/dL), and at subsequent follow-up visits, the enlarged parathyroid showed progressive shrinkage with eucalcemia and normalized PTH levels throughout 12 months of follow-up.

Conclusions

Rarely, remission of PHPT may occur after ultrasound-guided-FNAB performed on a hyperfunctioning parathyroid lesion.

Parathyroidectomy slows renal function decline in patients with primary hyperparathyroidism

PURPOSE

Primary hyperparathyroidism has deleterious effects on health and causes nephrolithiasis and osteoporosis. However, it remains unclear whether parathyroidectomy benefits kidney function among patients with primary hyperparathyroidism.

METHODS

In this retrospective study, patients with primary hyperparathyroidism receiving parathyroidectomy in a tertiary medical center between 2003 and 2017 were followed up until December 31 2017, death, or requiring renal replacement therapy. Impact of parathyroidectomy on kidney function was examined using longitudinal estimated glomerular filtration rate (eGFR) change scales: single, average, absolute difference, percent change, annual decline rate, and slope. We applied linear mixed-effect model to determine the effect of parathyroidectomy on kidney function.

RESULTS

During study period, 167 patients with primary hyperparathyroidism were identified from 498 parathyroidectomized patients, and finally, 27 patients fulfilled our stringent criteria. Median follow-up duration was 1.50 years (interquartile range 1.05-1.81) before surgery and 2.47 years (1.37-6.43) after surgery. Although parathyroidectomy did not affect amount of proteinuria and distribution of eGFR, parathyroidectomy significantly slowed decline rate of eGFR compared with that before surgery (- 1.67 versus - 2.73 mL/min/1.73 m²/year, p < 0.001). More importantly, parathyroidectomy made more beneficial effects on kidney function in patients with age < 65 years and those without chronic kidney disease or hypertension.

CONCLUSIONS

Our study showed that parathyroidectomy slows renal function decline irrespective of age or comorbidities, which offers novel insight into the revision of guidelines for surgical indications in primary hyperparathyroidism. Given small sample size, further large-scale controlled studies are warranted to confirm our findings.

Radioguided occult lesion localization for minimally-invasive parathyroidectomy without quick PTH monitoring and frozen section: impact of the learning curve

Objectives

Minimally-invasive parathyroidectomy (MIP) is a surgical procedure that reduces the duration of operation, hospital costs, and hypocalcemia, and shortens the length of hospital stay. This study addressed the important procedural details of the radioguided occult lesion localization (ROLL)-MIP technique and evaluated the consequences of the learning curve from a series of patients.

Patients and Methods

A total of 80 patients who underwent ROLL-MIP for a single parathyroid adenoma were included into this retrospective study. In order to analyze the effect of the learning curve, these subjects were then divided into 2 groups per time period and the operative times were compared. Group A consisted of 22 previously reported patients who served as the control group. Group B consisted of 58 consecutive patients.

Results

Serum calcium and parathyroid hormone (PTH) levels were normalized in all of the patients within 2 days and remained normal during the follow-up period (31 ± 18.5 months). None of the patients who underwent ROLL-guided parathyroidectomy suffered temporary or permanent recurrent laryngeal nerve injuries. Mean operation time (time from incision to excision of the adenoma) was 23 ± 6 min in Group A and 18 ± 7 min in Group B. Mean operative times were significantly shorter in group B.

Conclusion

The success of MIP administered with the ROLL technique in a single adenomatous patient was quite high. This method seems especially valuable in patients with atypically located or small adenomas.

Beyond Bone: Infectious Diseases and Immunity in Parathyroid Disorders

Parathyroid disorders are characterized by alterations in calcium and phosphate homeostasis due to inappropriately high or low levels of parathyroid hormone (PTH). Despite PTH receptor type 1 has been described in almost all immune lineages and calcium signalling has been confirmed as a crucial mediator for immune response, in vitro studies on the physiological interactions between PTH and immunity are conflicting and not representative of the clinical scenarios seen in patients with parathyroid disorders. Infectious diseases are among the main causes of increased morbidity and mortality in patients with secondary hyperparathyroidism and chronic kidney disease. More, immune alterations have been described in primary hyperparathyroidism. Recent studies have unveiled an increased risk of infections also in hypoparathyroidism, suggesting that not only calcium, but also physiological levels of PTH may be necessary for a proper immune response. Finally, calcium/phosphate imbalance could affect negatively the prognosis of infectious diseases. Our review aimed to collect available data on infectious disease prevalence in patients with parathyroid disorders and new evidence on the role of PTH and calcium in determining the increased risk of infections observed in these patients.

Factors That Affect the Sensitivity of Imaging Modalities in Primary Hyperparathyroidism

BACKGROUND

Cervical ultrasound, 99mTc-sestamibi single-photon emission computed tomography/computed tomography (99mTc-MIBI SPECT/CT), and cervical CT are routinely used in preoperative localization of primary hyperparathyroidism (PHPT). However, false-negative imaging results are also frequently encountered in clinical practice. Exploring the factors that affect the sensitivity of these imaging modalities is important for the surgical management of PHPT patients.

METHODS

Clinical data of 352 PHPT patients hospitalized in our center from January 2011 to December 2015 were retrospectively collected to evaluate the sensitivity of 3 imaging modalities in the preoperative localization of parathyroid lesions. The ROC curve analysis was used to explore the clinical factors affecting the sensitivity of localization, and the cut-point(s) of related factors were determined.

RESULTS

99mTc-MIBI SPECT/CT has the highest sensitivity among the localization modalities commonly used, reaching 91.1% (86.0%-94.8%). When the lengths of parathyroid lesions were ≤1.3 cm, the sensitivity of neck ultrasonography significantly decreased, while the sensitivity of 99mTc-MIBI SPECT/CT decreased with parathyroid lesions ≤1.3 cm or serum PTH≤252 pg/ml. 99mTc-MIBI SPECT/CT was less effective in localizing the hyperplasia lesions. Neck ultrasonography combined with 99mTc-MIBI SPECT/CT can effectively improve the accuracy of preoperative localization of parathyroid lesions to 96.2% (92.7%-98.1%).

CONCLUSIONS

Small parathyroid lesion and mild elevation of serum PTH would reduce the accuracy of parathyroid localization in PHPT patients.

Right ectopic paraesophageal parathyroid adenoma with refractory hypercalcemia in pregnancy: A case report and review of the literature

•

Ectopic parathyroid adenoma (EPA) is rare during pregnancy but poses multiple challenges in diagnosis and treatment.

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EPA presents with refractory hypercalcemia which leads to symptoms and complications in the mother and fetus.

•

Preoperative localization of EPA is important and allows for a focused surgical procedure.

•

Surgery is a definitive treatment and can safely be performed during the 2nd trimester of pregnancy.

Introduction

Ectopic parathyroid adenoma is rare during pregnancy but poses multiple challenges in treatment. It presents as primary hyperparathyroidism which leads to symptoms and complications of hypercalcemia in both the mother and fetus.

Presentation of case

A 38-year-old Sudanese female presented with diffuse bone pain and polyuria. Laboratory investigations revealed elevated serum calcium and parathyroid hormone. Ultrasound of the neck did not show any abnormal lesion, however 99mTc-sestamibi scan showed a right sided parathyroid adenoma, and an earlier CT scan showed the adenoma to be in an ectopic paraesophageal position. Focused surgical neck exploration was done, and the ectopic parathyroid adenoma was excised.

Discussion

Preoperative localization of the ectopic parathyroid adenoma allows for a focused surgical procedure. Ultrasound is the safest during pregnancy, but 99mTc-sestamibi and CT scan may be necessary if ultrasound or initial bilateral neck exploration do not detect any adenoma. Mild elevations in maternal serum calcium can have detrimental effects on the fetus which suggests that a surgical approach may be necessary in the majority of cases.

Conclusions

Ectopic parathyroid adenoma is rare during pregnancy and is detrimental to both the mother and fetus. Preoperative localization allows for a focused surgery which is a definitive treatment and can safely be performed during the 2nd trimester of pregnancy.

Severe bone disease caused by primary hyperparathyroidism: a case report and review of the literature

Bone disease is an important complication of hyperparathyroidism. We herein report a rare case of severe bone disease caused by primary hyperparathyroidism. A 33-year-old man presented with pain and restricted mobility in his right upper limb and right hip due to a fall 3 days previously. X-ray examination showed a fracture of the proximal and distal humerus. Computed tomography examination showed a supracondylar fracture of the right humerus, a fracture of the right femoral neck, a fracture of the right sciatic branch, and multiple brown tumors. Ultrasonography showed a 3.5- × 1.6-cm hypoechoic mass below the left lobe of the thyroid. The patient was diagnosed with primary hyperparathyroidism based on increased serum calcium and parathormone concentrations, pathological fractures, and multiple brown tumors. He therefore underwent bilateral lower parathyroidectomy. Pathological examination revealed a parathyroid adenoma. The patient recovered well after surgery and was followed up for 6 months with no symptoms of hyperparathyroidism. This case report suggests that clinicians should be aware of the possibility of severe bone disease secondary to primary hyperparathyroidism. Active and early diagnosis and surgical treatment are important in such cases.

Parathyroid carcinoma coexisting with multiple parathyroid adenomas: a case report

Primary hyperparathyroidism is usually caused by parathyroid adenoma; however, parathyroid carcinoma is a rare cause. We report a rare case of 74-year-old female of primary hyperparathyroidism caused by parathyroid carcinoma (PC) and coexisting multiple parathyroid adenomas. She was referred to our hospital for primary hyperparathyroidism and a suspected thyroid tumor. She had no family history of malignant tumor. Computed tomography (CT) and ultrasonography of the neck revealed some masses posterior to both thyroid lobes. Those masses were believed to be parathyroid lesions. However, another mass located posterior to the right upper thyroid lobe seemed to be heterogeneous, which indicated a malignant thyroid tumor as well as parathyroid tumor. The preoperative diagnosis was multiple parathyroid adenoma and suspicious incidental thyroid carcinoma. Therefore, the patient underwent total parathyroidectomy and thyroidectomy. The histopathological diagnosis was parathyroid carcinoma coexisting with multiple parathyroid adenomas. There was no evidence of recurrence at 1 year after the surgery. It was difficult to diagnose PC preoperatively. Few rare cases of PC coexisting with parathyroid adenoma in multiple endocrine neoplasia type 1 (MEN1) have been reported. Therefore, careful follow-up was necessary considering the possibility of MEN1, though she did not wish for a genetic examination.

Bone Mineral Density in Severely Obese Women: Health Risk and Health Protective Risk Factors in Three Different Bone Sites

Factors associated with bone mineral density (BMD) are poorly known in severely obese individuals i.e., a body mass index (BMI) > 35 kg/m2. The objectives of this study were to describe the bone health profile of severely obese Brazilian women, to identify the health risk and health protective factors for BMD in this group and to assess whether these factors vary according to three different bone sites. BMD was assessed using dual-energy X-ray absorptiometry (DXA). This study analyzed baseline data from 104 women who had an average BMI of 43.7 ± 4.5 kg/m2 and presented the following BMD status: 1.283 ± 0.094 g/cm2 for total body, 1.062 ± 0.159 g/cm2 for vertebral column and 1.195 ± 0.134 g/cm2 for hip. They took part in the "Effect of nutritional intervention and olive oil in severe obesity" randomized clinical trial (DieTBra Trial). The risk factors negatively associated with lower BMD were age ≥50 years for the three bone sites i.e., total body, vertebral column and hip. Smoking for total body BMD (p = 0.045); BMI ≥ 50kg/m2 for vertebral column and hip; menopause for hip; high C-reactive protein (CRP) levels (p = 0.049), insufficient zinc (p = 0.010) and previous fracture for vertebral column (p = 0.007). The protective factors positively associated with BMD were physical activity (≥150 min/week (p = 0.001)) for hip; type 2 diabetes mellitus (DM2) (p < 0.0001) total body and adequate vitamin D levels from food consumption (p = 0.039) for vertebral column. A BMI ≥ 50 kg/m2 was a risk factor for lower BMD. The findings showed that protective and risk factors varied by bone site. The original study is registered with ClinicalTrials.gov. (protocol number: NCT02463435).

Concomitant Primary Hyperparathyroidism in Patients with Multiple Myeloma: A Possible Link?

Hypercalcemia is a significant feature of patients with active multiple myeloma (MM) with extensive bone disease. Among the causes of non-neoplastic hypercalcemia, primary hyperparathyroidism (PHPT) is one of the most common, leading to osteoporosis and bone fractures. Interestingly, some preclinical data indicate that high secretion of parathyroid hormone (PTH) may have a negative impact on bone disease and MM progression. However, concomitant diagnosis of MM and PHPT has rarely been described. Here, we present 4 cases of patients with active MM and hypercalcemia with high or inappropriately normal PTH levels. Interestingly, CD138+ cells from these 4 MM patients lack PTH receptor 1 and PTH-related peptide expressions, indicating that PTH could have a paracrine rather than a direct pro-tumoral effect. Moreover, these cases suggest that the concomitant diagnosis of MM and PHTP may not be so rare and should be considered for the clinical management of MM patients with hypercalcemia.