Primary hyperparathyroidism

Impact of primary aldosteronism on calcium phosphate homeostasis. Results from the SPAIN-ALDO

PURPOSE

To determine the prevalence of hyperparathyroidism (HPT), including primary, secondary and normocalcemic in a cohort of patients with PA of the SPAIN-ALDO registry.

METHODS

A retrospective multicenter study of primary aldosteronism (PA) patients followed in 37 Spanish tertiary hospitals and with available information on serum calcium, phosphorus, iPTH, and vitamin D at the time of PA diagnosis. The diagnosis of normocalcemic HPT (n-HPT) associated with PA was based on a iPTH > 65pg/mL with normal corrected serum calcium after excluding the most common causes of secondary HPT, and HPT was classified as secondary (S-HPT) in the presence of chronic kidney disease or vitamin D deficiency, and as primary (PHPT) when iPTH levels >65 pg/mL were associated with high serum calcium levels.

RESULTS

A total of 246 patients with PA were included, of whom 56% (n = 139) had PTH > 65 pg/mL. In the group of participants with HPT (n = 139) the proportion of PHPT was 7.2%, of n-HPT 11.5% and of S-HPT 81.3%. Patients with n-HPT had a higher prevalence of atrial fibrillation (7.9% vs. 1.9%, P = 0.04) and hypokalemia (71.6% vs. 46.2%, P < 0.001) and greater aldosterone (33.2 vs. 26.8 ng/dL, p = 0.003) and 24 h urinary calcium excretion ( 243.5 vs. 160.5 mg/24 h, p = 0.01) than patients without hyperparathyroidism. No differences in surgical outcomes (biochemical and clinical response) were detected between patients with and without hyperparathyroidism.

CONCLUSIONS

HPT is a frequent condition in patients with PA and S-HPT is the most common etiology. Patients with HPT have a higher prevalence of atrial fibrillation and hypokalemia and a more severe PA than those without HPT. However, no differences in surgical outcomes were reported between patients with and without HPT.

Is unilateral approach under local anesthesia for parathyroidectomy feasible? A systematic review of literature

INTRODUCTION

Primary hyperparathyroidism (PHPT) is a common endocrine disease especially in postmenopausal women and in older adults, with elevated parathyroid hormone (PTH) levels by parathyroid glands. The main symptoms of PHPT are hypercalcemia, often associated with hypercalciuria, urolithiasis and bone demineralization that results in osteopenia or osteoporosis and increases overall fracture risk. Parathyroidectomy is today the only definitive treatment for patients to prevent worsening of symptoms. Minimally invasive targeted approach for parathyroidectomy can be offered to patients with well-localized disease, and combined with intraoperative PTH monitoring, the success rate reaches 95-97%; with short operative time, low complications rates and decreased hospital costs. To date, minimally invasive parathyroidectomy (MIP) can be performed under local anesthesia and most patients can be discharged on the same day of surgery or the following morning. The aim of this article is to summarize the current evidence of MIP under local anesthesia and its clinical outcomes to assess the effectiveness and safety of this procedure.

EVIDENCE ACQUISITION

We searched PubMed, Embase, Cochrane and Web of Science databases from their date of inception until 30th May 2024. Inclusion criteria consisted in articles from any country written in English reporting MIP under local anesthesia related clinical outcomes in humans. RCTs, quasi-RCTs, cross-sectional studies, retrospective and prospective cohort studies, case-control studies were included.

EVIDENCE SYNTHESIS

We identified 23 eligible studies that included 2470 adults (mostly female asymptomatic) with PHPT; follow-up duration varied from six months to 24 months. All studies were screened for assessments of quality based on Newcastle-Ottawa Scale and the risk of bias based on ROBIN-I of the included studies. The operative time, number of conversions to general anesthesia, hospital stay and complications was respectively: 43.86 minutes, with 114 conversions to general anesthesia, mean hospitalization time was 16.83±8.62 hours and complications reported in 71 patients. Previously of surgery, the abnormal parathyroid gland is localized using multiplexed ion beam imaging (MIBI) plus ultrasound (US) in 12 studies, only MIBI in three studies, thallium-technetium scan plus US in three studies, single-photon-emission computed tomography (SPECT) plus US in one study and a combination of MIBI, US, SPECT, CT and magnet resonance in one study. The mean preoperative value of PTH and serum calcium was 277.44 pg/mL and 11.49 mg/dL respectively; while the mean postoperative value of PTH and serum calcium was 46.18 pg/mL and 9.11 mg/dL respectively. At the definitive histology the most of pathology is adenoma with 542 cases reported, followed by hyperplasia with 35 cases and only 20 cases of carcinoma.

CONCLUSIONS

Focused mini-invasive parathyroidectomy under local anesthesia, guided by positive preoperative localization exams and accurate laboratory data, could be a feasible and effective surgical technique to cure primary hyperparathyroidism, with reduced operative time, a small surgical incision, shorter hospitalization stay and a lower occurrence of postoperative complications.

Persistence and Recurrence of Primary Hyperparathyroidism

Persistent and recurrent primary hyperparathyroidism (PHPT) represent significant challenges in the management of PHPT. Persistent PHPT is defined as persistence of hypercalcemia following parathyroidectomy (PTX) or the recurrence of hypercalcemia within the first 6 months following surgery. Recurrent PHPT is defined as recurrence of hypercalcemia after 6 months following PTX and requires normalization of serum calcium prior to the recurrence. These conditions are often attributed to missed or ectopic glands, multiglandular disease, surgeon inexperience, or rare causes such as parathyromatosis and parathyroid carcinoma. Diagnosis requires a detailed biochemical evaluation, imaging studies, and exclusion of other causes of hypercalcemia as well as secondary causes of hyperparathyroidism. Preoperative imaging modalities, including neck ultrasound, SPECT-CT with 99m Tc-sestamibi scan, 4D-CT, 18F-Fluorocholine PET/CT, and PET/MRI are helpful in localizing abnormal parathyroid glands in cases requiring repeat surgery. Repeat surgery is associated with higher risk and requires an experienced surgeon. When surgery is not indicated or possible, medical management with cinacalcet and antiresorptive therapies may be considered. This review highlights the etiology, diagnostic approaches, and management strategies for persistent and recurrent PHPT, emphasizing the importance of multidisciplinary care in order to optimize outcomes.

Pilot Study of Plasma miRNA Signature Panel for Differentiating Single vs Multiglandular Parathyroid Disease

CONTEXT

The ability to differentiate sporadic primary hyperparathyroidism (sPHPT) caused by a single parathyroid adenoma (PTA) from multiglandular parathyroid disease (MGD) preoperatively, as well as definitely diagnose sPHPT in difficult patients, would enhance surgical decision-making.

OBJECTIVE

This work aimed to identify miRNA (miR) signatures for MGD, single- and double-PTA, as well as cell-free miRNA (cfmiR) in plasma samples from patients with single-PTAs to use as biomarkers.

METHODS

A total of 47 patients with sPHPT (single-PTA n = 32, double-PTA n = 12, MGD n = 9). Preoperative plasma samples from 16 single-PTA and 29 normal healthy donors (NHDs). All specimens were processed and analyzed for 2083 miRs using HTG EdgeSeq miR whole-transcriptome assay and normalized using DESeq2 to identify differentially expressed (DE) miRs. MiR classifiers were identified using Random Forest. Main outcome measures were receiver operating characteristic curves and areas under the curve.

RESULTS

MiR signatures distinguished normal parathyroid from MGD and PTA as well as MGD from PTA in tissue samples. Common miRs were found in the single-PTA and double-PTAs. Data integration identified a 27-miR signature in single-PTA tissue samples compared to the rest of the tissue samples. In plasma samples analysis, significant cfmiRs were DE in single-PTA patients compared to NHD. Of those, only 9 miRNAs/cfmiRs were found DE both in tissue and plasma samples from patients diagnosed with a single PTA (AUC = 76%).

CONCLUSION

Twenty-seven miRs were consistently found DE in single-PTA tissue and plasma samples. Data integration showed a 9-cfmiR signature with potential clinical utility to preoperatively diagnose sPHPT caused by a single PTA, which could decrease more invasive parathyroid explorations.

Chapter 2: Primary Hyperparathyroidism: diagnosis

Primary hyperparathyroidism is now predominantly an asymptomatic pathology, as blood calcium assay has become systematic. Diagnosis therefore requires screening for target organ damage when this is not already indicative of primary hyperparathyroidism. Classical clinical manifestations include bone, kidney and muscle signs, and are characterized by reversibility after parathyroid surgery. Their presence requires blood calcium assay. Non-classical manifestations include cardiovascular, digestive and neuropsychological signs, which are not known to be reversible after surgery. Positive diagnosis is biological, based on a parathyroid hormone value that is inappropriate to the blood calcium value. The typical form combines hypercalcemia, elevated parathyroid hormone and increased calciuria or calcium excretion fraction. Atypical forms combine either hypercalcemia and normal parathyroid hormone level, or normal calcemia with increased parathyroid hormone level, not necessarily secondary to another cause, such as 25(OH) vitamin D deficiency. The oral calcium loading test and the Pro-FHH score are contributive to diagnosis in atypical forms.

Calcium to magnesium ratio as a superior biomarker for nephrolithiasis detection in primary hyperparathyroidism

Primary hyperparathyroidism (pHPT) is marked by mineral imbalances, often leading to nephrolithiasis and osteoporosis. While imaging remains the cornerstone for stone detection, there is growing interest in biochemical markers that could enhance diagnostic accuracy. This study investigates the calcium-to-magnesium (Ca/Mg) ratio as a novel biomarker for nephrolithiasis, comparing its utility to traditional 24-h urinary calcium excretion and exploring its broader clinical implications. In this retrospective study of 367 pHPT patients, clinical, biochemical, and bone mineral density (BMD) data were analyzed. Nephrolithiasis was diagnosed via imaging, and the diagnostic performance of the Ca/Mg ratio and urinary calcium excretion was assessed through receiver operating characteristic analysis. Multivariable regression was employed to identify predictors of kidney stones. The Ca/Mg ratio, with an optimal cutoff of 6.35, demonstrated superior specificity (78%) compared to 24-h urinary calcium excretion (44%) while maintaining comparable sensitivity (71% vs. 78%). Elevated Ca/Mg ratios strongly correlated with nephrolithiasis, independent of other demographic factors. Hypomagnesemia was linked to a higher prevalence of kidney stones, reduced BMD, and increased serum calcium and creatinine levels, emphasizing its impact on skeletal and renal health. The Ca/Mg ratio emerges as a promising, non-invasive biomarker for nephrolithiasis in pHPT, outperforming traditional urinary calcium measures. It reflects underlying mineral imbalances and offers a practical tool for risk stratification and clinical decision-making. These findings underscore the need for further research into magnesium-targeted interventions, which may transform the management of pHPT-related complications.

Beyond secondary hyperparathyroidism: Diagnosing primary parathyroid abnormalities in a patient with chronic kidney disease

Chronic kidney disease (CKD) is a complex medical condition that extends beyond the progressive decline in renal function. It is associated with mineral and bone disorders, notably secondary hyperparathyroidism due to dysregulated calcium and phosphate metabolism. However, distinguishing between secondary and primary hyperparathyroidism can be challenging. We report the case of a 74-year-old male with CKD, who presented with elevated serum levels of parathyroid hormone (PTH), CKD, and unexplained hypercalcemia, despite management for secondary hyperparathyroidism. Advanced imaging techniques revealed a primary parathyroid adenoma, subsequently confirmed by histopathology. The successful surgical resection of the adenoma resulted in the calcium and PTH levels falling into a normal range, highlighting the need for a careful differential diagnosis in CKD patients.

Primary Hyperparathyroidism: A Common Condition With an Uncommon Location

Primary hyperparathyroidism (PHPT) is a prevalent clinical condition characterized by an inappropriate secretion of parathyroid hormone (PTH). It is most often caused by one or more parathyroid adenomas, which can, in rare cases, be ectopically located. Ectopic adenomas can pose a diagnostic challenge, lead to treatment delay, and be a common cause of recurrent hypercalcemia after parathyroidectomy. We present the case of a 73-year-old woman referred to our Endocrinology Department for hypercalcemia, with initial blood tests confirming primary hyperparathyroidism. Following a negative cervical ultrasound, a parathyroid sestamibi scan was performed, which identified an MIBI (technetium (Tc)-99m methoxyisobutylisonitrile)-avid focus in the midline posterior cervical region suggestive of an ectopic parathyroid adenoma. Subsequently, a four-dimensional neck CT scan revealed a retro-esophageal nodular lesion. The diagnosis was confirmed through esophageal endoscopic ultrasound-guided fine needle aspiration. The patient underwent minimally invasive parathyroidectomy with a significant intraoperative decrease in PTH levels and a postoperative normalization of calcium levels. Six months after surgery the patient shows no signs of recurrence. This clinical case highlights the importance of a thorough diagnostic workup and the use of multiple imaging modalities to accurately locate parathyroid adenomas. This approach helps prevent incorrect surgical procedures and improves treatment outcomes.

68Ga-Trivehexin PET/CT: a promising novel tracer for primary hyperparathyroidism

INTRODUCTION

This study aims to assess 68Ga-Trivehexin PET/CT for detecting hyperfunctioning parathyroid tissue in comparison to [99mTc]Tc-MIBI scintigraphy-SPECT/CT (MIBI scan) in patients with primary hyperparathyroidism (PHPT).

METHODS

The cohort comprised 13 patients diagnosed with PHPT based on biochemical analyses, including serum calcium, phosphorus, and parathyroid hormone (PTH) levels. Each participant underwent cervical ultrasonography, MIBI scan, and 68Ga-Trivehexin PET/CT imaging. Complementary 4D-CT and [18F]fluorocholine PET/CT were conducted in 7 patients. Ten lesions of 7 patients underwent PTH wash-out (WO) procedure. 68Ga-Trivehexin PET/CT findings were compared with other modalities and PTH-WO results.

RESULTS

Ten patients had sporadic PHPT, while 3 were diagnosed with MEN-1 syndrome-associated PHPT. One patient did not have any identifiable parathyroid lesion across the imaging modalities. On a patient-based analysis, MIBI scan and 68Ga-Trivehexin PET/CT identified parathyroid lesions in 10 and 11 patients, respectively. However, 68Ga-Trivehexin PET/CT detected 7 additional parathyroid lesions that were negative on the MIBI scan. Consequently, 17 lesions were identified and confirmed as hyperfunctioning parathyroid tissue through imaging, PTH-WO, or a combination of both modalities. In lesion-based evaluation, 68Ga-Trivehexin identified 16 lesions compared to 10 by MIBI scan, resulting in a detection rate of 94.1% and 58.8%, respectively. Notably, in three patients who underwent [18F]fluorocholine PET/CT, no lesions were detected; yet 68Ga-Trivehexin PET/CT successfully identified parathyroid lesions in two of these patients.

CONCLUSION

Our study provides the first evidence that 68Ga-Trivehexin PET/CT can effectively identify hyperfunctioning parathyroid tissue with a high detection rate warranting further investigations to comprehensively explore its potential in PHPT management.

Primary hyperparathyroidism-induced acute pancreatitis in pregnancy: A systematic review with a diagnostic-treatment algorithm

BACKGROUND

Primary hyperparathyroidism (PHPT)-induced acute pancreatitis (AP) during pregnancy has rarely been described. Due to this rarity, there are no diagnostic or treatment algorithms for pregnant patients.

AIM

To determine appropriate diagnostic methods, therapeutic options, and factors related to maternal and fetal outcomes for PHPT-induced AP in pregnancy.

METHODS

A literature search of articles in English, Japanese, German, Spanish, and Italian was performed using PubMed (1946-2023), PubMed Central (1900-2023), and Google Scholar. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) protocol was followed. The search terms included "pancreatite acuta," "iperparatiroidismo primario," "gravidanza," "travaglio," "puerperio," "postpartum," "akute pankreatitis," "primärer hyperparathyreoidismus," "Schwangerschaft," "Wehen," "Wochenbett," "pancreatitis aguda," "hiperparatiroidismo primario," "embarazo," "parto," "puerperio," "posparto," "acute pancreatitis," "primary hyperparathyroidism," "pregnancy," "labor," "puerperium," and "postpartum." Additional studies were identified by reviewing the reference lists of retrieved studies. Demographic, imaging, surgical, obstetric, and outcome data were obtained.

RESULTS

Fifty-four cases were collected from the 51 studies. The median maternal age was 29 years. PHPT-induced AP starts at the 20th gestational week; higher gestational weeks were seen in mothers who died (mean gestational week 28). Median values of amylase (1399, Q1-Q3 = 519-2072), lipase (2072, Q1-Q3 = 893-2804), serum calcium (3.5, Q1-Q3 = 3.1-3.9), and parathormone (PTH) (384, Q1-Q3 = 123-910) were reported. In 46 cases, adenoma was the cause of PHPT, followed by 2 cases of carcinoma and 1 case of hyperplasia. In the remaining 5 cases, the diagnosis was not reported. Neck ultrasound was positive in 34 cases, whereas sestamibi was performed in 3 cases, and neck computed tomography or magnetic resonance imaging was performed in 9 cases (the enlarged parathyroid gland was not localized in 3 cases). Surgery was the preferred treatment during pregnancy in 33 cases (median week of gestation 25, Q1-Q3 = 20-30) and postpartum in 12 cases. The timing was not reported in the remaining 9 cases, or surgery was not performed. AP was managed surgically in 11 cases and conservatively in 43 (79.6%) cases. Maternal and fetal mortality was 9.3% (5 cases). Surgery was more common in deceased mothers (60.0% vs 16.3%; P = 0.052), and PTH values tended to be higher in this group (910 pg/mL vs 302 pg/mL; P = 0.059). Maternal mortality was higher with higher serum lipase levels and earlier delivery week. Higher calcium (4.1 mmol/L vs 3.3 mmol/L; P = 0.009) and PTH (1914 pg/mL vs 302 pg/mL; P = 0.003) values increased fetal/child mortality, as well as abortions (40.0% vs 0.0%; P = 0.007) and complex deliveries (60.0% vs 8.2%; P = 0.01).

CONCLUSION

If serum calcium is not tested during admission, definitive diagnosis of PHPT-induced AP in pregnancy is delayed, while early diagnosis and immediate intervention lead to excellent maternal and fetal outcomes.

Kidney Stone Risk in Normocalcemic Hyperparathyroidism before and after Parathyroid Surgery

The higher risk for kidney stone in patients with primary hyperparathyroidism is well-documented; stone risk in patients with normocalcemic primary hyperparathyroidism (NPHPT) remains unclear. We present a case of recurrent calcium kidney stones in a patient with severe idiopathic hypercalciuria and NPHPT. The surgical resection of the parathyroid adenoma failed to reduce kidney stone risk (based on the 24-hr urine study) and kidney stone burden (based on ultrasound). This unique case examines the impact of surgical resection of an ectopic parathyroid adenoma on stone risk in a patient with NPHPT and recurrent calcium kidney stones.

Diagnostic Performance of 99mTc-Sestamibi SPECT/CT and 18F-Choline PET/CT in Locating Hyperfunctioning Parathyroid Glands in Patients with Primary Hyperparathyroidism

OBJECTIVE

This study aimed to assess the diagnostic performance of 99mTc-sestamibi SPECT/CT and 18F-choline PET/CT in detecting hyperfunctioning parathyroid glands in patients undergoing surgery for primary hyperparathyroidism (PHPT).

METHODS

A retrospective analysis was conducted on patients who underwent PHPT-related surgery between April 2019 and May 2022. The study focused on patients undergoing either 99mTc-sestamibi SPECT/CT (81 patients) or 18F-choline PET/CT (33 patients) scans before surgery to pinpoint hyperfunctioning parathyroid gland(s). In the majority of patients, 18F-choline PET/CT was performed after negative or inconclusive findings on 99mTc-sestamibi SPECT/CT. Pathohistological reports were utilized as the reference standard for evaluating the accuracy of the imaging findings.

RESULTS

The study encompassed 83 patients (70 females, 84.3%) with an average age of 57.2 years (24-80 years). The pathohistological analysis identified a total of 98 glands. In a per-lesion analysis, the detection rate of 99mTc-sestamibi SPECT/CT was 57% (95% CI 45.3-68.1), while the detection rate of 18F-choline PET/CT was 90.3% (95% CI 74.3-98.0).

CONCLUSION

The results of our study showed the significant usefulness of 18F-choline PET/CT in patients with negative or inconclusive results of 99mTc-sestamibi SPECT/CT in accurately locating hyperfunctioning parathyroid glands in PHPT patients.

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.

Insights into Hyperparathyroidism-Jaw Tumour Syndrome: From Endocrine Acumen to the Spectrum of CDC73 Gene and Parafibromin-Deficient Tumours

A total of 1 out of 10 patients with primary hyperparathyroidism (PHP) presents an underlying genetic form, such as multiple endocrine neoplasia types 1, 2A, etc., as well as hyperparathyroidism-jaw tumour syndrome (HJT). We aimed to summarise the recent data, thus raising more awareness regarding HJT, from the clinical perspective of PHP in association with the challenges and pitfalls of CDC73 genetic testing and parafibromin staining. This narrative review included a sample-focused analysis from the past decade according to a PubMed search. We identified 17 original human studies (≥4 patients per article). The mean age at disease onset was between 20.8 and 39.5 years, while the largest study found that 71% of patients had HJT recognised before the age of 30. Males and females seemed to be equally affected, in contrast with sporadic PHP. PHP represented the central manifestation of HJT, occurring as the first manifestation in up to 85% of HJT cases. A biochemistry panel found a mean serum calcium level above the level of 12 mg/dL in PHP. PTH was elevated in HJT as well, with average values of at least 236.6 pg/mL. The most frequent pathological type in PHP was a parathyroid adenoma, but the incidence of a parathyroid carcinoma was much higher than in non-HJT cases (15% of all parathyroid tumours), with the diagnosis being established between the age of 15 and 37.5. In some families up to 85% of carriers suffered from a parathyroid carcinoma thus indicating that certain CDC73 pathogenic variants may harbour a higher risk. An important issue in HJT was represented by the parafibromin profile in the parathyroid tumours since in HJT both parathyroid adenomas and carcinomas might display a deficient immunoreactivity. Another frequent manifestation in HJT was ossifying fibromas of the jaw (affecting 5.4% to 50% of patients; the largest study found a prevalence of 15.4%). HJT was associated with a wide variety of kidney lesion (mostly: kidney cysts, with a prevalence of up to 75%, and renal tumours involved in 19% of patients). The risk of uterine lesions seemed increased in HJT, especially with concern to leiomyomas, adenofibromas, and adenomyosis. The underlying pathogenic mechanisms and the involvement of CDC73 pathogenic variants and parafibromin expression are yet to be explored. Currently, the heterogeneous expression of parafibromin status and, the wide spectrum of CDC73 mutations including the variety of clinical presentations in HJT, make it difficult to predict the phenotype based on the genotype. The central role of HJT-PHP is, however, the main clinical element, while the elevated risk of parathyroid carcinoma requires a special awareness.

The calcium-clot connection: investigating the association between primary hyperparathyroidism and acute venous thromboembolism

Primary hyperthyroidism (PHPT) is a relatively uncommon disease and leads to increased calcium levels. Ionized calcium, known as clotting Factor IV, may lead to overt coagulation cascade activation, increasing the risk of venous thromboembolism (VTE). National Inpatient Sample Database was used to sample individuals with primary hyperparathyroidism, and baseline demographics and comorbidities were collected using ICD-10 codes. Patients with missing data and age less than 18 were excluded. Moreover, patients with other types of hyperparathyroidism and risk factors for VTE, such as malignancy, thrombophilia, chronic kidney and liver disease, fractures, trauma, oral contraceptive/steroid use, and organ transplant, were excluded. Greedy propensity matching using R was performed to match patients with and without primary hyperparathyroidism on age, race, gender, and 10 other comorbidities, including chronic deep venous thromboembolism. Univariate analysis pre- and post-match were performed. Binary logistic regression was performed after matching to assess whether primary hyperparathyroidism was an independent risk factor for acute VTE. A p-value of  < 0.05 was considered statistically significant. Out of 460,529 patients included in the study, 1114 (6.5%) had PHPT. Baseline comorbidities were more common in the PHPT group. On univariate analysis, patients with PHPT were more likely to have acute VTE (2.5% vs. 1.4%; p < 0.001). After 1:1 matching, PHPT patients were twice as likely to have Acute VTE. (OR: 2.1 [1.08-4.1]; p < 0.025). These findings suggest an association between PHPT and VTE, which should be further investigated to prevent the increasing incidence of VTE and its recurrence.

Approach to the Patient With Parathyroid Carcinoma

Parathyroid carcinoma (PC) is usually associated with severe symptomatic primary hyperparathyroidism (PHPT) and accounts for less than 1% of all cases of PHPT and approximately 0.005% of all cancers. PC most commonly occurs as a sporadic disease and somatic CDC73 mutations can be detected in up to 80% of cases. Approximately 30% of patients harbor a germline mutation of the CDC73 gene. Preoperative diagnosis of PC is difficult because no disease-specific markers are available, and PC should be suspected in patients with severe hypercalcemia and end-organ complications. The diagnosis is based on the evidence of invasive tumor growth at histology and/or metastases. En bloc resection of the tumor, together with the ipsilateral thyroid lobe and adjacent structures, should be performed by an experienced surgeon when PC is suspected. This surgical approach reduces the risk of recurrence and metastasis and offers the highest chance of cure. Nonetheless, PC has a recurrence rate of 40% to 60% and, if feasible, multiple surgical procedures should be performed. When surgery is no longer an option, medical treatment is aimed to reduce hypercalcemia and target organ complications. Targeted agents have been effectively used in a few cases. We describe herein a patient with severe PHPT due to PC and provide a systematic diagnostic and treatment approach. A thorough review of the medical history, a typical clinical and biochemical phenotype and, in some cases, the revision of the histological examination provide the clues for the diagnosis of PC.

Vitamin D Deficiency and the Presentation of Primary Hyperparathyroidism: A Mini Review

The clinical presentation of primary hyperparathyroidism (PHPT) has evolved over the years from a symptomatic disorder to a predominantly asymptomatic condition. Altered vitamin D metabolism seems to play a role in the presentation of PHPT and may exacerbate the severity of disease. The epidemiology of PHPT differs in the developing versus the developed world, where more severe phenotypes occur in regions where vitamin D deficiency is common. Although it has been validated that patients with PHPT should be vitamin D sufficient, the threshold to supplement in relation to the severity of PHPT and the degree of vitamin D deficiency remains controversial. This review will highlight some of the controversy regarding vitamin D deficiency and the different phenotypes of PHPT.

The prevalence of primary and secondary hyperparathyroidism and its cardiometabolic implications in primary aldosteronism

BACKGROUND

The aim of this study was to analyze the prevalence of primary and secondary hyperparathyroidism in patients with primary aldosteronism (PA), and its implication on cardiovascular and metabolic outcomes.

METHODS

A retrospective study of patients with PA (exposed cohort, N.=44) and all hypertensive (EH) patients with adrenal lesions without PA nor other adrenal hypersecretion (non-exposed cohort, N.=41) on follow-up at our center between 2016 and 2020.

RESULTS

The mean age of patients with PA and EH was 55.1±14.13 and 66.3±10.93 (P<0.001), and 50% of PA and 39.0% of EH were women (P=0.309). At diagnosis, the prevalence of primary hyperparathyroidism in PA was of 18.2%, and all were normocalcemic hyperparathyroidism cases. Globally, no differences were found in the prevalence of primary hyperparathyroidism compared to EH (18.2% vs. 29.3%, P=0.229), but hypercalcemic primary hyperparathyroidism was significantly more prevalent in EH patients than in PA (22.0% vs. 0%, P=0.001). There were 47.7% (N.=21) cases of secondary hyperparathyroidism in patients with PA (4 due to chronic kidney disease (CKD) and vitamin D deficiency, and 17 due to vitamin D deficiency alone). The cardiometabolic profile of patients with PA and hyperparathyroidism (N.=29) was similar to of those patients without hyperparathyroidism (N.=15) at diagnosis and after a median follow-up of 3.6 years (interquartile range 1.1-5.9).

CONCLUSIONS

Although primary and secondary hyperparathyroidism are common in patients with PA, their prevalence was similar than the observed in EH patients. Primary hyperparathyroidism is usually mild in PA, appearing as normocalcemic forms. No negative implications of the hyperparathyroidism in the cardiometabolic profile of PA were observed.

Delayed Diagnosis of Primary Hyperparathyroidism: A Case Report

Primary hyperparathyroidism (PHPT) is characterized by an elevation in serum calcium levels, sometimes leading to aggravated clinical conditions, namely nephrolithiasis, nephrocalcinosis, and/or fractures. A 55-year-old patient was admitted to the hospital with acute obstructive pyelonephritis in March 2021, having another episode one year later. Initial blood and urine analysis detected inflammatory markers, namely C-reactive protein, and the presence of leucocytes and blood in the urine. The renal computed tomography scan exhibited renal asymmetry, nephrocalcinosis, and multiple kidney stones. The patient was scheduled for a follow-up one year later to perform blood and urine analysis to uncover the cause of nephrocalcinosis, displaying high serum calcium and parathyroid hormone (PTH) levels. The thyroid ultrasound revealed a parathyroid adenoma, which was removed through a right lower parathyroidectomy, improving the symptoms. The clinical condition described here is an atypical manifestation of this disease because PHPT is normally asymptomatic. In the present case study, nephrocalcinosis and nephrolithiasis were strong indicators of the underlying disease. However, the delay in the follow-up consultation resulted in complications for the patient, such as microabscesses in the kidneys, which could lead to reduced renal function in the future. Early detection of key aspects of the disease could avoid further complications and suffering for the patient. For example, the family physician's follow-up of the patient's condition could surpass the waiting time between consultations with different specialties, and promote early treatment.

Peripheral giant cell granuloma as a sign of hyperparathyroidism in a patient under hemodialysis: A case report and review of literature

Peripheral giant cell granuloma (PGCG) is a benign reactive exophytic oral lesion that originates from the periosteum or the periodontal ligament. It exclusively develops on the gingiva or alveolar mucosa. Hyperparathyroidism (HPT) is a possible etiology for its development. HPT is an endocrine disorder characterized by increased secretion of the parathyroid hormone (PTH). This case report describes a case of recurring PGCG in a patient diagnosed with secondary HPT after paraclinical assessment.

Severe hypercalcemia secondary to parathyroid adenoma: Series of four consecutive cases at a tertiary care hospital in Qatar

INTRODUCTION

In most cases of parathyroid adenoma (PA), it is not palpable and physical examination shows no remarkable findings. Hence diagnosis requires an index of suspicion. The current paper describes four cases of severe hypercalcemia secondary to PA.

PRESENTATION OF CASES

Case 1 - 29 years old Sudanese female with history of nausea/vomiting, fatigue, loss of appetite and bone aches. She had large palpable left lower neck swelling, and high calcium and PTH. Ultrasound (US) neck and SPECT/CT scan after sestamibi injection showed left inferior PA. Case 2-73 years old Sudanese male referred with history of abdominal pain and flatulence. He had severely high calcium, elevated parathormone (PTH), and high 24-hour urine calcium. US and SPECT/CT showed a left inferior PA. Case 3-54 years old Bangladeshi male, referred with history of renal colic/urolithiasis. Laboratory results showed severely high calcium and PTH levels. US and SPECT/CT scan showed right inferior PA. Case 4-35 years old Tunisian female, 12 weeks pregnant, referred with recurrent nausea and vomiting of increasing frequency from the second week of pregnancy. Laboratory tests revealed severe hypercalcemia and high PTH. US showed two parathyroid lesions.

DISCUSSION

The patients were admitted as emergency cases and investigations diagnosed severe hypercalcemia secondary to PA. All patients underwent neck exploration and PA excision. Histology confirmed PA. The four cases were swiftly assessed and treated before progressing into the more serious hypercalcemic crisis which can lead to grave consequences, particularly in the case of the pregnant female. All patients recovered with no complications and were clinically well with normal calcium level on follow up.

CONCLUSION

Severe hypercalcemia must be swiftly and thoroughly assessed to prevent the more serious hypercalcemic crisis. Clinicians need to be suspicious of parathyroid adenoma as a probable cause. Severe hypercalcemia is often accompanied with vomiting, and in pregnant females, this could be mistaken for hyperemesis gravidarum. Excision of the parathyroid adenoma treats the condition and follow up of serum calcium and PTH confirms the favorable outcome of surgery.

Cystic Parathyroid Adenomas as a Risk Factor for Severe Hypercalcemia

(1) Background: Parathyroid cystic adenomas (PCA) are rare entities representing only 0.5-1% of parathyroid adenomas, accounting for 1-2% of cases of primary hyperparathyroidism (PHPT). The purpose of this study was to compare classical and functional/secreting cystic parathyroid lesions and identify risk factors for severe hypercalcemia; (2) Methods: A total of 17 patients with PHPT and parathyroid cysts (study group) were compared with the group of 100 patients with hyperparathyroidism caused by adenoma or hyperplasia (control group). In both groups the majority were women (88% vs. 12%, with gender ratio 7, 3:1). The patients were examined preoperatively and postoperatively: PTH, creatine, calcium and phosphate serum and urine concentrations and calcidiol serum levels were assessed; (3) Results: Patients with parathyroid cyst had statistically higher PTH and calcium serum concentration, higher calciuria and lower serum phosphate concentration. There were no statistically significant differences in the concentration of creatine in serum and urine and tubular reabsorption of phosphorus (TRP); (4) Conclusions: Due to higher PTH and calcium levels, cystic parathyroid adenomas could be one of the rare risk factors for severe hypercalcemia and hypercalcemic crisis which can be life threatening.

Recurrent parathyromatosis in a patient with concomitant MEN1 and CASR gene alterations: Clinical management of a case report and literature review

Introduction

Parathyromatosis is a rare cause of primitive hyperparathyroidism characterized by the presence of numerous parathyroid tissue foci in the neck/mediastinum, due to hyperplasia of parathyroid embryologic residues (primary-form) or to local parathyroid tissue implantation (secondary-form). 63 cases have been described in the literature. In our patient parathyromatosis was due to a combination of two mutations.

Case report

A 36-years-old woman was diagnosed with osteoporosis secondary to primary hyperparathyroidism. Subsequent right parathyroidectomy showed a parathyroid adenoma. The follow-up was negative but after 10 years she had a relapse. The genetic screening showed a rare intronic mutation of the MEN1 gene and a heterozygous mutation never described in exon 8 of the CASR gene, coding for the calcium receptor. Calcemia and PTH increased over the years with the onset of nephrocalcinosis and the worsening of osteoporosis despite the therapy with Cinacalcet, bisphosphonates and Vitamin D. She had therefore two additional surgical procedures (parathyroid tissue without malignancy). At follow-up she showed elevated levels of PTH (>1000 pg/ml) and calcium (11.2 mg/dl) and CT scans multiple subcentimetric nodules in the neck/upper mediastinum. Since the 68Ga-DOTATATE showed an increased uptake in the neck/mediastinum, lanreotide was added. After two months there was a significant biochemical response but, unfortunately, after six months, the patient showed a new worsening.

Conclusions

a rare case of parathyromatosis due to a combination of two genetic alterations never described. The main issues concern the diagnosis and the radical treatment. Somatostatin analogues may have a useful role in both diagnosis and therapy.

Uncommon presentation of brown tumours revealing hyperparathyroidism: Three case reports

Brown tumours (BTs) are focal bone lesions encountered in patients with uncontrolled hyperparathyroidism (HPT). They are due to a proliferation of multinucleated giant cells in osteolytic lesions. Because of early screening of bone metabolism disorders, BTs are rare bone manifestations. More importantly, they scarcely reveal the disease. We demonstrate through these two cases reports unusual locations of BT complicating the course of HPT due to parathyroid hyperplasia.

Clinical predictors of ectopic parathyroid adenomas: experience with 421 confirmed parathyroid adenoma localizations

PURPOSE

This study was designed to evaluate whether patients with ectopic parathyroid adenoma (EPA) have clinical predictors by comparing them with other patients operated on for primary hyperparathyroidism (PHPT) with uniglandular parathyroid adenomas in other localizations.

METHODS

The data of PHPT patients who underwent parathyroidectomy in our institution were assessed retrospectively. Abnormal gland localization was confirmed by operative and pathology reports as well as normocalcemia that lasted for at least 6 months postoperatively. The relationships of biochemical and clinical findings of patients with confirmed adenoma localizations were analyzed. In order to determine independent factors that can predict EPAs, binary logistic regression was used.

RESULTS

Among 421 patients (83.4% female, mean age 49 ± 13.2 years) enrolled in the study, the most common adenoma localization was the lower left parathyroid gland (36.1%; p < 0.001). Parathyroid adenomas were more common in lower localizations compared to upper localizations and were smaller in size (p < 0.001 and p = 0.004, respectively). In univariate analysis, serum intact parathyroid hormone and calcium levels were found to be higher (p = 0.004 and p = 0.002, respectively), moderate/severe hypercalcemia was more common (p = 0.024), phosphorus levels were lower (p = 0.04), and postoperative transient hypocalcemia was more common (p = 0.013) in cases of EPAs than other localizations. There was no significant difference in adenoma size between EPAs and other classical localizations. In multivariate analysis, only a high serum calcium level was an independent predictor of EPAs (OR 2.017, 95% CI 1.142-3.564, p = 0.016). Receiver-operating characteristic curve analysis yielded an optimal cutoff value of 12.25 mg/dL for serum calcium (88% sensitivity, 63% specificity, and area under the curve: 0.861).

CONCLUSION

EPAs can cause a more biochemically distinct PHPT picture compared to parathyroid adenomas in classical localizations. A high calcium level at diagnosis may be a clinical predictor for EPAs and may affect the clinical approach and imaging technique choices. Due to the increased risk of transient hypocalcemia in patients with EPAs, caution should be exercised in postoperative follow-up. Furthermore, in the event of negative preoperative imaging, starting the parathyroid exploration from the lower left region may be a good option for the surgeon.

Medical management of primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is an endocrine disorder resulting from the hyperfunction of one or more parathyroid glands, with hypersecretion of parathyroid hormone (PTH). It can be managed by parathyroidectomy (PTX) or non-surgically. Medical therapy with pharmacological agents is an alternative for those patients with asymptomatic PHPT who meet guidelines for surgery but are unable or unwilling to undergo PTX. In this review, we focus upon these non-surgical aspects of PHPT management. We emphasize the most studied and widely used pharmacological alternatives: bisphosphonates, denosumab, cinacalcet and hormone therapy, in addition to combined therapy. We also address the relevant aspects of perioperative management.

Update on Preoperative Parathyroid Localization in Primary Hyperparathyroidism

Parathyroidectomy is the treatment of choice for primary hyperparathyroidism when the clinical criteria are met. Although bilateral neck exploration is traditionally the standard method for surgery, minimally invasive parathyroidectomy (MIP), or focused parathyroidectomy, has been widely accepted with comparable curative outcomes. For successful MIP, accurate preoperative localization of parathyroid lesions is essential. However, no consensus exists on the optimal approach for localization. Currently, ultrasonography and technetium-99m-sestamibi-single photon emission computed tomography/computed tomography are widely accepted in most cases. However, exact localization cannot always be achieved, especially in cases with multiglandular disease, ectopic glands, recurrent disease, and normocalcemic primary hyperparathyroidism. Therefore, new modalities for preoperative localization have been developed and evaluated. Positron emission tomography/computed tomography and parathyroid venous sampling have demonstrated improvements in sensitivity and accuracy. Both anatomical and functional information can be obtained by combining these methods. As each approach has its advantages and disadvantages, the localization study should be deliberately chosen based on each patient's clinical profile, costs, radiation exposure, and the availability of experienced experts. In this review, we summarize various methods for the localization of hyperfunctioning parathyroid tissues in primary hyperparathyroidism.

Long-term outcome of surgical techniques for sporadic primary hyperparathyroidism in a tertiary referral center in Belgium

PURPOSE

Surgery remains the only permanent treatment option for primary hyperparathyroidism (pHPT). To date, the number of long-term outcome studies of parathyroidectomy is limited. This study aims to compare different surgical approaches and evaluate the importance of preoperative localization imaging in the treatment of pHPT.

METHODS

All 200 consecutive patients with a parathyroidectomy for sporadic pHPT without planned concomitant surgery between 09/2009 and 04/2021 in a Belgian tertiary referral hospital were enrolled. All patients underwent at least two preoperative localization imaging studies (neck ultrasound, CT, SPECT, and/or Sestamibi scintigraphy) of the parathyroid glands. The main outcomes were the (long-term) cured proportion and postoperative morbidity (hypocalcemia, recurrent laryngeal nerve palsy, return to theater for bleeding, and wound morbidity).

RESULTS

Most patients were referred with concordant positive imaging (82%, n = 164). Only nine patients (4.5%) had double negative imaging, not revealing a possible adenoma. The remaining 27 (13.5%) were referred with discordant imaging. Parathyroidectomy was performed via traditional cervicotomy (30%), mini-open approach (39.5%), or endoscopic approach (30.5%). Morbidity was low with no persistent hypocalcemia, one return to theater for bleeding, and no 30-day mortality. In the concordant imaging population, 13 patients (8%) had multiglandular disease. Overall, 97.5% was considered cured. Long-term recurrence was 12% with a minimal follow-up of 5 years.

CONCLUSION

This consecutive, single-surgeon, single-center cohort with extensive data collection and long-term follow-up confirms the safety and excellent cured proportions of minimally invasive parathyroidectomy. Disease recurrence becomes more important long after surgery.

Predicting ultrasound-guided thermal ablation benefit in primary hyperparathyroidism

OBJECTIVES

Ultrasound (US)-guided thermal ablation for primary hyperparathyroidism (PHPT) is a relatively novel minimally invasive treatment. The recurrence rate after ablation is between 10 and 15%. The characteristics of patients who can benefit from thermal ablation therapy are not clear yet. The aim of this research was to investigate the validity of a parathyroid hormone (PTH)-based classifier for stratifying patients with PHPT.

METHODS

A total of 171 patients were screened, 148 (86.5%) of whom were eligible and were divided into development (n = 104) and external validation (n = 44) cohorts. The potential relationship between the PTH-based classifier and the cure rate of patients was initially assessed in the primary cohort and then validated in the external validation cohort. The nomogram was computed from the logistic regression model.

RESULTS

A cut-off of PTH < 269.1 pg/mL or ≥ 269.1 pg/mL as the optimal prognostic threshold in the training cohort was generated to stratify the patients into low-risk and high-risk groups. Patients with PTH levels < 269.1 pg/mL in the training cohort had a higher cure rate than patients with PTH levels ≥ 269.1 pg/mL (p < 0.001). The PTH level remained the strongest predictor of the cure rate in all cohorts. Furthermore, a nomogram based on the PTH level was developed to predict the cure rate in the training cohort and it performed well in the external validation cohort (AUC: 0.816, 95%CI 0.703 to 0.930; AUC: 0.816, 95%CI 0.677 to 0.956).

CONCLUSIONS

The PTH-based classifier may help with individualised treatment planning for selecting patients who may benefit from thermal ablation.

KEY POINTS

• This is the first analysis of predictors affecting the outcome of US-guided thermal ablation of primary hyperparathyroidism and the findings can be used to identify the potential beneficiary population of thermal ablation of primary hyperparathyroidism. • Parathyroid hormone (PTH) was confirmed as an independent prognostic factor, as it not only showed good accuracy in stratifying patients into high- and low-risk groups in the training and validation cohorts but also outperformed the clinical model. • This study developed and validated a model to predict the treatment success of thermal ablation of primary hyperparathyroidism.

Genetic Disorders of Calcium and Phosphorus Metabolism

In this review, we describe genetic mutations affecting metabolic pathways of calcium and phosphorus homeostasis. Calcium and phosphorus homeostasis has tight hormonal regulation by three major hormones: vitamin D, parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23). We describe the physiology and pathophysiology of disorders, their biochemical profile, clinical characteristics, diagnostics, and treatments.

Neglected analytes in the 24-h urine: ammonium and sulfate

PURPOSE OF REVIEW

Evaluation of the kidney stone patient includes measurement of 24 h urine chemistries. This review summarizes the application of physiologic principles to the interpretation of urine chemistries, using sulfate and ammonium to estimate diet acid load, and the renal response.

RECENT FINDINGS

There has been increased recognition of the need to measure urine ammonium excretion in the clinical setting in order to understand renal acid excretion. Some 24 h urine kidney stone panels include ammonium measurements, providing an opportunity to apply this measurement to clinical practice. In order to better interpret ammonium excretion, one needs an estimate of dietary acid load to understand the driving forces for ammonium excretion. Sulfate is also included in some kidney stone panels and functions as an estimate of diet acid load. Combining these analytes with urine pH, the clinician can quickly estimate dietary stone risk as well as potential bowel disease, acidification disorders, and the presence of urease producing bacteria; all of which can affect stone risk.

SUMMARY

Measurement of ammonium and sulfate excretion along with urine pH provide important insights into the acid/alkali content of diet, presence and severity of bowel disease, presence of renal acidification disorders, and urinary infection.

Editorial on the Special Issue "Novel Methods of Diagnostics of Thyroid and Parathyroid Lesions"

Thyroid nodular disease is one of the most frequent endocrine diseases [...].

John MA, Stafsudd O. Ex vivo hypercellular parathyroid gland differentiation using dynamic optical contrast imaging (DOCI)

Primary hyperparathyroidism, often caused by a single adenoma (80-85%) or four-gland hyperplasia (10-15%), can lead to elevated parathyroid hormone (PTH) levels and resultant hypercalcemia. Surgical excision of offending lesions is the standard of care, as the removal of pathologic adenomas reduces PTH and calcium values to baseline. The small size, variable location, and indistinct external features of parathyroid glands can make their identification quite challenging intraoperatively. Our group has developed the dynamic optical contrast imaging (DOCI) technique, a novel realization of dynamic temporally dependent measurements of tissue autofluorescence. In this study, we evaluated the efficacy of using the DOCI technique and normalized steady-state fluorescence intensity data for differentiating types of human parathyroid and thyroid tissues. We demonstrate that the DOCI technique has the capability to distinguish normal parathyroid tissue from diseased parathyroid glands as well as from adjacent healthy thyroid and adipose tissue across 8 different spectral channels between 405nm-600nm (p<0.05). Patient tissue DOCI data was further analyzed with a logistic regression classifier trained across the 8 spectral channels. After computer training, the computer-aided identification was able to accurately locate hypercellular parathyroid tissue with 100% sensitivity and 98.8% specificity within the captured DOCI image.

Hyperparathyroidism: Unusual location of brown tumors

Brown tumors (BTs) are due to a proliferation of multinucleated giant cells in osteolytic lesions. They complicate the course of hyperparathyroidism. Thanks to an early screening of bone metabolism disorders; BTs are nowadays rare bone manifestations. We demonstrate through these two cases reports unusual locations of BTs in hyperparathyroidism.

Irisin and Secondary Osteoporosis in Humans

Irisin is a peptide secreted by skeletal muscle following exercise that plays an important role in bone metabolism. Numerous experiments in vitro and in mouse models have shown that the administration of recombinant irisin promotes osteogenesis, protects osteocytes from dexamethasone-induced apoptosis, prevents disuse-induced loss of bone and muscle mass, and accelerates fracture healing. Although some aspects still need to be elucidated, such as the dose- and frequency-dependent effects of irisin in cell cultures and mouse models, ample clinical evidence is emerging to support its physiological relevance on bone in humans. A reduction in serum irisin levels, associated with an increased risk of osteoporosis and bone fractures, was observed in postmenopausal women and in both men and women during aging, Recently, cohort studies of subjects with secondary osteoporosis showed that these patients have lower circulating levels of irisin, suggesting that this myokine could be a novel marker to monitor bone quality in this disease. Although there are still few studies, this review discusses the emerging data that are highlighting the involvement of irisin in some diseases that cause secondary osteoporosis.

Translation of the Pasieka's Parathyroid Assessment of Symptoms Questionnaire (PAS-Q) for Use in the Greek Population

INTRODUCTION

In Europe, primary hyperparathyroidism is mainly considered an asymptomatic disorder, although there is evidence that patients' health-related quality of life is impaired. This aspect is mostly evaluated using Pasieka's Questionnaire: a disease-specific diagnostic tool. The purpose of this study was to translate the Pasieka's Questionnaire into the Greek language and adapt it to the Greek population.

MATERIALS AND METHODS

Pasieka's Questionnaire consists of 13 questions. Two bilingual, native Greek experts were selected for step one, each of whom offered a blinded Greek version of the questionnaire. In the second step, these two versions were merged into one which was retranslated back into the English language (step three) by two bilingual translators (English native speakers). In the fourth step, a committee was formed to draft the pre-final version of the questionnaire which was then submitted to the co-authors for final approval. Finally, after the approval of the final version, 50 patients with primary hyperparathyroidism were recruited for the pilot study of the questionnaire.

RESULTS

All 13 questions of the Pasieka's Questionnaire were translated without any major discrepancy. A high level of internal consistency was achieved (Cronbach's alpha was 0.904) and agreement between test-retest was excellent for every question.

CONCLUSION

The Greek version of Pasieka's Questionnaire was validated and can be applied to evaluate the health-related quality of life of patients with primary hyperparathyroidism in Greek-speaking populations.

Sporadic Primary Hyperparathyroidism

Sporadic primary hyperparathyroidism is a common endocrinopathy, particularly afflicting postmenopausal women and both African American men and women. Although classic signs and symptoms of the disease are well appreciated and described, because of the ease and availability and low threshold for screening, the disorder often is diagnosed in patients who are minimally symptomatic or asymptomatic. Surgery conducted by experienced endocrine surgeons has a high cure rate, particularly if guided by concordant imaging. In patients who cannot safely undergo surgery or who fail to be cured, medical therapy with the oral calcimimetic cinacalcet is a validated option for controlling serum calcium levels.

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.

Ex Vivo Intact Tissue Analysis Reveals Alternative Calcium-sensing Behaviors in Parathyroid Adenomas

CONTEXT

The biochemical basis for clinical variability in primary hyperparathyroidism (PHPT) is poorly understood.

OBJECTIVE

This study aimed to define parathyroid tumor biochemical properties associated with calcium-sensing failure in PHPT patients, and to relate differences in these profiles to variations in clinical presentation.

METHODS

Preoperative clinical data from a sequential series of 39 patients undergoing surgery for PHPT at an endocrine surgery referral center in a large, public university hospital were evaluated for correlation to parathyroid tumor biochemical behavior. An intact tissue, ex vivo interrogative assay was employed to evaluate the calcium-sensing capacity of parathyroid adenomas relative to normal donor glands. Tumors were functionally classified based on calcium dose-response curve profiles, and clinical parameters were compared among the respective classes. Changes in the relative expression of 3 key components in the calcium/parathyroid hormone (PTH) signaling axis-CASR, RGS5, and RCAN1-were evaluated as potential mechanisms for calcium-sensing failure.

RESULTS

Parathyroid adenomas grouped into 3 distinct functional classes. Tumors with diminished calcium sensitivity were the most common (18 of 39) and were strongly associated with reduced bone mineral density (P = 0.0009). Tumors with no calcium-sensing deficit (11 of 39) were associated with higher preoperative PTH (P = 0.036). A third group (6/39) displayed a nonsigmoid calcium/PTH response curve; 4 of these 6 tumors expressed elevated RCAN1.

CONCLUSION

Calcium-sensing capacity varies among parathyroid tumors but downregulation of the calcium-sensing receptor (CASR) is not an obligate underlying mechanism. Differences in tumor calcium responsiveness may contribute to variations in PHPT clinical presentation.

Dysmagnesemia Is the Most Common Disturbance of the Calcium-Magnesium-Phosphorous Balance among Older Hospitalized People in Warsaw

The elderly are at great risk of developing life-threatening disturbances in calcium–magnesium–phosphate homeostasis because of comorbidities, long-term medication use, and dietary deficiencies, but it is still not known how often they occur in this group of patients. This study aimed to assess the prevalence of these disturbances in a group of hospitalized patients over 65 years of age according to age and sex. The study was conducted between January 2018 and September 2020 at the Central Clinical Hospital in Warsaw. A total of 66,450 calcium, magnesium, phosphate, and vitamin D concentration results were included in the analysis. Dysmagnesemia was present in 33% of the calcium results, dyscalcemia, dysphosphatemia, and dysvitaminosis D—in 23.5%, 26%, and 70% of the results, respectively. The magnesium concentration was found to be age-dependent, and older people were found to be at higher risk of developing abnormal magnesium concentrations (p < 0.001). Sex influenced the occurrence of abnormal magnesium (p < 0.001), vitamin D (p < 0.001), and calcium (p < 0.00001) concentrations, with hypercalcemia and hypervitaminosis D disorders being significantly more common in women (p < 0.0001). In conclusion, disorders of the calcium–magnesium–phosphate metabolism are common in hospitalized patients over 65 years of age, and the concentrations of these substances should be routinely monitored in this group.

Association between hypomagnesemia and severity of primary hyperparathyroidism: a retrospective study

BACKGROUND

The occurrence of hypomagnesemia in patients with primary hyperparathyroidism (PHPT) has been noted previously; however, the association of hypomagnesemia and severity of primary hyperparathyroidism remains unknown. The present study aimed to evaluate the association of hypomagnesemia with biochemical and clinical manifestations in patients with PHPT.

METHODS

This was a retrospective study conducted at a tertiary hospital. We obtained data from 307 patients with PHPT from January 2010 through August 2020. Data on demographics, history, laboratory findings, bone densitometry findings, and clinical presentation and complications were collected and were compared in normal magnesium group vs hypomagnesemia group.

RESULTS

Among the 307 patients with PHPT included in our study, 77 patients (33/102 [32.4%] males and 44/205 [21.5%] females) had hypomagnesemia. Mean hemoglobin levels in the hypomagnesemia group were significantly lower than those in the normal magnesium group in both males and females. In contrast, patients with hypomagnesemia had a higher mean serum calcium and parathyroid hormone than individuals with normal magnesium. The typical symptoms of PHPT, such as nephrolithiasis, bone pain/fractures, polyuria, or polydipsia, were more common in the hypomagnesemia group. In addition, patients with hypomagnesemia had a higher prevalence of osteoporosis, anemia, and hypercalcemic crisis. Even after adjusting for potential confounders, including age, sex, body mass index, estimated glomerular filtration rate, and parathyroid hormone levels, these associations remained essentially unchanged.

CONCLUSION

Biochemical and clinical evidence indicates that patients with PHPT with hypomagnesemia have more severe hyperparathyroidism than those without hypomagnesemia. In addition, PHPT patients with hypomagnesemia had a higher prevalence of osteoporosis, anemia, and hypercalcemic crisis.

Primary Hyperparathyroidism – A Contemporary Picture Based on 100 Patients from the Last Decade

Primary hyperparathyroidism (PHPT) is an endocrine disease, the clinical picture of which has slowly shifted to milder and asymptomatic forms during the last decades.

Objective

to describe the clinical presentation and the main laboratory and imaging findings in a group of patients with PHPT diagnosed during the last 10 years.

Materials and Methods

This was a retrospective cross-sectional study with data review from the database of a tertiary endocrine clinic from the last 10 years. Secondary causes for elevated PTH were excluded. The major clinical symptoms and signs of hypercalcemia/HPT were reviewed as well as concomitant diseases and medications. Serum calcium (total, albumin-corrected and ionized; sCa, corrCa, iCa+), phosphates (P), magnesium, creatinine, alkaline phosphatase, beta-crosslinks were measured. The intact parathyroid hormone (iPTH) and 25(OH)-vitamin D were determined by electro-hemi-luminescence (Elecsys, Roche Diagnostics). 24-hour urinary probes for calcium and phosphate were collected. Neck ultrasound (US) was used as the localization study of choice. Almost half of the participants underwent fine-needle aspiration biopsy (FNAB) with cytology and needle-washouts for iPTH. One fourth of the patients were assessed by Single-Photon Emission Tomography (SPECT-CT). Data on bone density (from DXA), fractures and renal stones (from renal US) were collected.

Results

One hundred patients met the study criteria – 95 were women. Most of them were in their 5th and 6th decades. The median corrected sCa was 2.73 mmol/l, iCa+ – 1.39 mmol/l, P – 0.88 mmol/l, iPTH – 14.5 pmol/l and 25(OH)D – 54.0 nmol/l. Normal sCa was registered in 20 participants (20%), while normal sP – in 67.0%. The neck US located single lesions (parathyroid adenoma) in 81% – behind or below the left inferior pole of the thyroid gland in 33 cases (33%) and contra-laterally in another 33%. FNAB of the suspicious lesion had been performed in 51% of the study subjects. The cytology confirmed the presence of parathyroid cells in 22 cases (43.1%), Bethesda II thyroid nodules in 21 cases (41.2%), Bethesda III nodules in 2 cases (3.9%) and insufficient samples (Bethesda I) in 5 cases (9.8%). SPECT-CT from 27 patients identified a suspicious left parathyroid in 11 cases, a right one – in 6 cases, as well as three ectopic locations. BMD data were available in 66 female patients and showed a higher prevalence of osteoporosis than in the general age-matched population; fractures, however, were not more frequent. Data from renal ultrasound were available in 77% and revealed chronic pyelonephritis without stones in 8 patients and renal stone disease – in 37 patients.

Conclusion

To our knowledge, this study is the first of its kind in our country during the last two decades. Mild to moderate hypercalcemia was very common, although most patients were oligoor asymptomatic. Renal and bone involvement were surprisingly frequent, with reduced eGFR and low bone mass being more prevalent than in the general population. The most typical location was a single parathyroid lesion within the lower glands. The use of SPECT-CT seems to decline and is replaced by US-guided FNAB with needle washout measurements of iPTH and cytological examination. Although the general picture of PHPT is shifting towards milder and asymptomatic (and probably earlier) forms of the disease, the classical clinical presentation can still be found in everyday practice.

Aldosterone Secretion in Patients With Primary Hyperparathyroidism Without Arterial Hypertension

OBJECTIVE

There is a direct bidirectional link between parathyroid hormone (PTH) and the renin-angiotensin-aldosterone system (RAAS), but few studies evaluated the RAAS in patients with primary hyperparathyroidism (PHPT), mainly biased from concomitant antihypertensive treatment.

METHODS

We retrospectively evaluated a consecutive series of 130 normotensive patients with PHPT comparing aldosterone (ALD) levels and plasma renin activity (PRA) with the demographic, biochemical, or clinical features of PHPT.

RESULTS

No correlation was found between ALD and PRA, and the demographic, biochemical, and bone densitometry parameters in patients with PHPT without hypertension, with the exception of a negative correlation between age and serum PRA. Moreover, there was no significant correlation between PTH and ALD levels even in patients whose PTH level was >100 ng/L (P = .088).

CONCLUSION

In our normotensive patients with PHPT, the ALD, PRA, and aldosterone/renin ratio were not correlated to PTH and calcium levels. In addition, they were neither related to PHPT clinical presentation nor renal function, vitamin D status, bone mass loss, or the presence of comorbidities such as diabetes and obesity. Further studies are needed to clarify the complex interplay between PTH and the RAAS in the modern PHPT presentation.

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

OBJECTIVE

To identify and understand parathyroid lesions of patients with primary hyperparathyroidism (PHPT) more accurately under ultrasound.

METHODS

This 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.

RESULTS

According 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).

CONCLUSION

The PHPT nodules distinguished by ultrasound echogenicity features showed different histopathologic components, reflected by different clinical characteristics of the patients with PHPT.

Parathyroid Disease in Pregnancy and Lactation: A Narrative Review of the Literature

Pregnancy and lactation are characterized by sophisticated adaptations of calcium homeostasis, aiming to meet fetal, neonatal, and maternal calcium requirements. Pregnancy is primarily characterized by an enhancement of intestinal calcium absorption, whereas during lactation additional calcium is obtained through resorption from the maternal skeleton, a process which leads to bone loss but is reversible following weaning. These maternal adaptations during pregnancy and lactation may influence or confound the presentation, diagnosis, and management of parathyroid disorders such as primary hyperparathyroidism or hypoparathyroidism. Parathyroid diseases are uncommon in these settings but can be severe when they occur and may affect both maternal and fetal health. This review aims to delineate the changes in calcium physiology that occur with pregnancy and lactation, describe the disorders of calcium and parathyroid physiology that can occur, and outline treatment strategies for these diseases in the above settings.

The Risk of Fractures in Primary Hyperparathyroidism: A Meta-Analysis

Primary hyperparathyroidism (PHPT) is a common metabolic bone disease affecting 1% of the adult population. Patients with PHPT have reduced BMD, especially at the cortical bone. However, studies evaluating its impact on fracture risk have shown contradictory results. In an effort to further inform fracture risk for this patient population, a meta-analysis of studies of fracture in patients with PHPT compared with a control population was undertaken. Articles were searched in PubMed/MEDLINE, Excerpta Medica, Cochrane Central Register of Controlled Trials, Latin American and Caribbean Health Sciences Literature, and Web of Science bibliographic databases. The meta-analysis included 17 studies involving 3807 PHPT cases and 11,908 controls. The primary outcome was to determine the risk of vertebral fracture (VF), nonvertebral fracture, hip fracture, distal radius fracture, and total fracture (TF) among patients with PHPT in comparison with a control population. BMD (lumbar spine, femoral neck, total hip, and distal radius) and serum 25-hydroxy vitamin D level, as well as possible predictors of VF as secondary outcomes were assessed. From this meta-analysis, it was found that there was a significantly increased risk of VF (risk ratio [RR], 2.57; 95% CI, 1.3-5.09; p = 0.007) and TF (RR, 1.71; 95% CI, 1.48-1.97; p < 0.00001) in patients with PHPT. There was a significant decrease in BMD in patients with PHPT versus controls at all four sites. Older age, longer duration since menopause, and lower BMD at lumbar spine and distal radius were predictors for VF. To conclude, patients with PHPT had a significantly higher risk for VF and TF in comparison with controls. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Hypercalcemic Crisis Caused by a Parathyroid Mass Requiring Thoracoscopic Resection

Objective

To describe the presentation, work up, and treatment of a giant parathyroid adenoma presenting as hypercalcemic crisis that ultimately weighed 57 g and extended into the mediastinum, requiring hand-assisted thoracoscopic resection.

Methods

The patient is a 68-year-old man with a prior history of parathyroidectomy, who initially presented with a severe hypercalcemia of 16.3 mg/dL and a parathyroid hormone (PTH) level of 2692 pg/mL on routine labs.

Results

Diagnostic and staging work up revealed a 7.2-cm mass extending from just superior to the sternal notch into the right posterior mediastinum to the carina, causing esophageal displacement. No evidence of local invasion or distant metastasis was observed on further imaging, and cytology demonstrated hypercellular parathyroid tissue. The PTH level of the aspirate was >5000 pg/mL. The patient subsequently underwent a right hand-assisted video-assisted thoracoscopic resection of the intrathoracic mass. Final pathology identified a 7.0-cm, 57-g parathyroid adenoma, without any pathologic findings suspicious for malignancy. However, the endocrine surgery team plans for annual laboratory assessment to ensure no recurrence.

Conclusion

Primary hyperparathyroidism is most commonly caused by a single adenoma. However, in the setting of severe hypercalcemia and elevated PTH, one must have a high suspicion for malignancy, and care should be taken to remove the mass en bloc. For extremely large adenomas extending into the mediastinum, a minimally invasive, hand-assisted, thoracoscopic approach is a safe and effective method of resection.

Systemic diseases and the cornea

There is a number of systemic diseases affecting the cornea. These include endocrine disorders (diabetes, Graves' disease, Addison's disease, hyperparathyroidism), infections with viruses (SARS-CoV-2, herpes simplex, varicella zoster, HTLV-1, Epstein-Barr virus) and bacteria (tuberculosis, syphilis and Pseudomonas aeruginosa), autoimmune and inflammatory diseases (rheumatoid arthritis, Sjögren's syndrome, lupus erythematosus, gout, atopic and vernal keratoconjunctivitis, multiple sclerosis, granulomatosis with polyangiitis, sarcoidosis, Cogan's syndrome, immunobullous diseases), corneal deposit disorders (Wilson's disease, cystinosis, Fabry disease, Meretoja's syndrome, mucopolysaccharidosis, hyperlipoproteinemia), and genetic disorders (aniridia, Ehlers-Danlos syndromes, Marfan syndrome). Corneal manifestations often provide an insight to underlying systemic diseases and can act as the first indicator of an undiagnosed systemic condition. Routine eye exams can bring attention to potentially life-threatening illnesses. In this review, we provide a fairly detailed overview of the pathologic changes in the cornea described in various systemic diseases and also discuss underlying molecular mechanisms, as well as current and emerging treatments.