Parathyroid fine needle aspiration with PTH washout: Can it lead to parathyroid cell seeding in primary hyperparathyroidism?

Although parathyroid fine-needle aspiration (P-FNA) with parathyroid hormone (PTH) washout is effective in detecting preoperative parathyroid lesions, it also presents risks such as fibrosis, hematoma, and, in rare cases, tumor seeding. This study aimed to investigate whether P-FNA with PTH washout leads to the seeding of parathyroid cells along the path of the needle. A retrospective analysis was conducted on patients undergoing minimally invasive parathyroidectomy guided by preoperative PTH washout. Permanent pathology reports, imaging data, and postoperative serum parathyroid hormone and calcium levels were assessed to determine the effectiveness and safety of the procedure. Complications following P-FNA with PTH washout were also reviewed using data from the patient registration system of Bulent Ecevit University. The procedure accurately localized parathyroid adenomas in 87 patients who underwent ultrasound-guided parathyroidectomy following preoperative P-FNA and PTH washout. Postoperatively, 75 patients showed normal parathyroid hormone and calcium levels. Two patients required secondary surgery for contralateral adenomas. Critically, there was no evidence of P-FNA with PTH washout-induced parathyromatosis or seeding during the follow-up. Effective adenoma localization is crucial for successful minimally invasive surgery of hyperparathyroidism. Our study indicates that combining preoperative P-FNAB with PTH washout and imaging enhances adenoma detection, especially when intraoperative PTH measurements are not available, thus improving surgical outcomes. Notably, we found no evidence of cell implantation after P-FNA, suggesting the safety and efficacy of this method for preventing parathyroid cell seeding.

Preoperative Lateralization and Diagnostic Value of Selective Bilateral Internal Jugular Venous Sampling in Primary Hyperparathyroidism: Single-Center Experience.

Background and Objectives: Primary hyperparathyroidism (pHPT) is a common endocrine disorder caused by excessive production of parathyroid hormone (PTH) leading to elevated calcium levels. Diagnosis is primarily based on biochemical evaluation, and surgery is the curative treatment. Imaging techniques like ultrasound and Tc-99m Sestamibi scintigraphy are used for localization, but selective Internal Jugular Venous (SVS) becomes valuable in cases of inconclusive or conflicting results. This study evaluated the diagnostic efficacy of SVS for localizing parathyroid adenomas in cases where non-invasive radiological diagnostic methods yielded inconclusive results or negative findings despite clinical symptoms suggestive of pHPT. Materials and Methods: In this retrospective study, a total of 28 patients diagnosed with pHPT underwent SVS at a tertiary center known for receiving referrals from 2017 to 2022. The diagnoses were confirmed through biochemical analysis. The SVS results in 22 patients were compared with non-invasive imaging methods, including ultrasound, scintigraphy, and computed tomography with/without contrast material. SVS was indicated when at least two non-invasive diagnostic procedures failed to clearly localize the parathyroid glands or provided ambiguous results. Results: SVS demonstrated higher sensitivity for localizing parathyroid adenomas compared to non-invasive imaging methods, accurately lateralizing the adenoma in 68.18% of cases. Among the SVS findings, 31.8% of patients had negative results, with 9.1% not having clinically proven parathyroid adenoma, while 22.7% had false negative SVS findings but were later confirmed to have adenoma during surgery. Ultrasound correctly identified the location in 45.45% of cases, CT in 27.27%, and scintigraphy in 40.9%. Conclusions: SVS is a valuable diagnostic tool for accurately localizing parathyroid adenomas in patients with inconclusive non-invasive imaging results. It aids in targeted surgical interventions, contributing to improved management and treatment outcomes in primary hyperparathyroidism.

Testing for Primary Hyperparathyroidism in 17,491 Patients With Hypercalcemia.

BACKGROUND: Primary hyperparathyroidism (PHPT) is underdiagnosed and associated with many adverse health effects. Historically, many hypercalcemic patients have not received parathyroid hormone (PTH) testing; however, underlying reasons are uncertain. Our goals are to determine the PTH testing rate among hypercalcemic individuals at a large academic health system and to assess for characteristics associated with testing versus not testing for PHPT to inform future strategies for closing testing gaps. METHODS: This retrospective study included adult patients with ≥1 elevated serum calcium result between 2018 and 2022. Based on the presence or absence of a serum PTH result, individuals were classified as "screened" versus "unscreened" for PHPT. Demographic and clinical characteristics of these groups were compared. RESULTS: The sample comprised 17,491 patients: 6567 male (37.5%), 10,924 female (62.5%), mean age 59 y. PTH testing was performed in 6096 (34.9%). Characteristics independently associated with the greatest odds of screening were 5+ elevated calcium results (odds ratio [OR] 5.02, P < 0.0001), chronic kidney disease (OR 3.63, P < 0.0001), maximum calcium >12.0 mg/dL (OR 2.48, P < 0.0001), and osteoporosis (OR 2.42, P < 0.0001). Characteristics associated with lowest odds of screening were age <35 y (OR 0.60, P < 0.0001), death during the study period (OR 0.68, P < 0.0001), age ≥85 y (OR 0.70, P = 0.0007), and depression (OR 0.84; P = 0.0081). CONCLUSIONS: Only 35% of hypercalcemic patients received PTH testing. Although the presence of PHPT-associated morbidity was generally associated with increased rates of screening, hypercalcemic patients with depression were 16% less likely to be tested.

Modern Trends for Primary Hyperparathyroidism: Intervening on Less Biochemically Severe Disease.

INTRODUCTION: Primary hyperparathyroidism (PHPT) is defined by autonomous parathyroid hormone secretion, which has broad physiologic effects. Parathyroidectomy is the only cure and is recommended for patients demonstrating symptomatic disease and/or end organ damage. However, there may be a benefit to intervening before the development of complications. We sought to characterize institutional trends in the biochemical and symptomatic presentation of PHPT and the associated cure and complication rates. METHODS: We performed a retrospective cohort study of 1087 patients undergoing parathyroidectomy for PHPT, evaluating patients at 2-year intervals between 2002 and 2019. We identified signs and symptoms of PHPT based on the 2016 American Association of Endocrine Surgery Guidelines. Trends were evaluated with Kruskal Wallis, Chi-square tests, and Fisher's exact tests. RESULTS: Patients with PHPT are presenting with lower parathyroid hormone (P = 0.0001) and calcium (P = 0.001) in the current era. Parathyroidectomy is more commonly performed for borderline guideline concordant patients with osteopenia (40.2%) and modest calciuria (median 246 mg/dL/24 h). 93.7% are cured, with no difference over time or between groups by guideline concordance. CONCLUSIONS: Parathyroidectomy is increasingly performed for patients who demonstrate modest bone and renal dysfunction. Patients experience excellent cure rates and rarely experience postoperative hypocalcemia, suggesting a role for broader surgical indications.

Neonatal hypocalcaemic seizures unmasking asymptomatic maternal primary hyperparathyroidism.

Hypocalcaemia is a common cause of neonatal seizures. Here, we present a breastfed neonate with smooth perinatal transition and no family history of seizures presenting at 3 weeks with recurrent multifocal clonic seizures. On evaluation, the neonate was found to have low iCa and total calcium. 25-hydroxy vitamin D (25(OH)D) level was low and intact parathyroid hormone (iPTH) was inappropriately normal. The maternal evaluation revealed high calcium and low phosphate levels. iPTH was very high and 25(OH)D was very low in the mother. Sestamibi scan showed a left inferior parathyroid adenoma in the mother. Maternal primary hyperparathyroidism causing hypercalcaemia can suppress parathyroid activity in the fetus, resulting in inappropriate parathyroid response to hypocalcaemia after birth causing recurrent hypocalcaemic seizures. So neonatal hypocalcaemic seizures need careful evaluation of the neonate and the mother at times and can help both mother and neonate.

Clinical and outcome comparison of genetically positive vs. negative patients in a large cohort of suspected familial hypocalciuric hypercalcemia.

OBJECTIVE: Biochemical suspicion of familial hypocalciuric hypercalcemia (FHH) might provide with a negative (FHH-negative) or positive (FHH-positive) genetic result. Understanding the differences between both groups may refine the identification of those with a positive genetic evaluation, aid management decisions and prospective surveillance. We aimed to compare FHH-positive and FHH-negative patients, and to identify predictive variables for FHH-positive cases. DESIGN: Retrospective, national multi-centre study of patients with suspected FHH and genetic testing of the CASR, AP2S1 and GNA11 genes. METHODS: Clinical, biochemical, radiological and treatment data were collected. We established a prediction model for the identification of FHH-positive cases by logistic regression analysis and area under the ROC curve (AUROC) was estimated. RESULTS: We included 66 index cases, of which 30 (45.5%) had a pathogenic variant. FHH-positive cases were younger (p = 0.029), reported more frequently a positive family history (p < 0.001), presented higher magnesium (p < 0.001) and lower parathormone levels (p < 0.001) and were less often treated for hypercalcemia (p = 0.017) in comparison to FHH-negative cases. Magnesium levels showed the highest AUROC (0.825, 95%CI: 0.709-0.941). The multivariate analysis revealed that family history and magnesium levels were independent predictors of a positive genetic result. The predictive model showed an AUROC of 0.909 (95%CI: 0.826-0.991). CONCLUSIONS: The combination of magnesium and a positive family history offered a good diagnostic accuracy to predict a positive genetic result. Therefore, the inclusion of magnesium measurement in the routine evaluation of patients with suspected FHH might provide insight into the identification of a positive genetic result of any of the CaSR-related genes.

Genetics of hereditary forms of primary hyperparathyroidism.

Primary hyperparathyroidism (PHPT), a relatively common disorder characterized by hypercalcemia with raised or inappropriately normal serum parathyroid hormone (PTH) concentrations, may occur as part of a hereditary syndromic disorder or as a non-syndromic disease. The associated syndromic disorders include multiple endocrine neoplasia types 1-5 (MEN1-5) and hyperparathyroidism with jaw tumor (HPT-JT) syndromes, and the non-syndromic forms include familial hypocalciuric hypercalcemia types 1-3 (FHH1-3), familial isolated hyperparathyroidism (FIHP), and neonatal severe hyperparathyroidism (NS-HPT). Such hereditary forms may occur in > 10% of patients with PHPT, and their recognition is important for implementation of gene-specific screening protocols and investigations for other associated tumors. Syndromic PHPT tends to be multifocal and multiglandular with most patients requiring parathyroidectomy with the aim of limiting end-organ damage associated with hypercalcemia, particularly osteoporosis, nephrolithiasis, and renal failure. Some patients with non-syndromic PHPT may have mutations of the MEN1 gene or the calcium-sensing receptor (CASR), whose loss of function mutations usually cause FHH1, a disorder associated with mild hypercalcemia and may follow a benign clinical course. Measurement of the urinary calcium-to-creatinine ratio clearance (UCCR) may help to distinguish patients with FHH from those with PHPT, as the majority of FHH patients have low urinary calcium excretion (UCCR < 0.01). Once genetic testing confirms a hereditary cause of PHPT, further genetic testing can be offered to the patients' relatives and subsequent screening can be carried out in these affected family members, which prevents inappropriate testing in normal individuals.

Patient perspectives on barriers to obtaining surgery for primary hyperparathyroidism: A qualitative review.

BACKGROUND: The purpose of this study was to qualitatively explore patient-reported barriers to surgery for primary hyperparathyroidism (PHPT) and identify actionable interventions to improve access to surgical care. METHODS: We recruited forty-nine patients in an endocrine surgery clinic at a large, academic medical to participate in an 11- question phone interview. All interviewees underwent parathyroidectomy for primary hyperparathyroidism. Responses were recorded and a codebook of qualitative themes, blinded to patient race and sex, was created by 3 independent reviewers. Comments were subsequently sorted into the codebook with patient demographic information. RESULTS: Patients that experienced delays in parathyroidectomy most commonly cited "issues with the referral process" and "missed diagnosis" as the cause. Patients were asked to identify the most challenging part about the surgery process. Commonly evoked themes among patients of both races and sexes included "transportation" and "financial" with subthemes of "no ride," "distance from surgeon," "insurance," and "difficulty taking time off work." Patients were asked to name actionable interventions to improve access to surgical care. The most commonly evoked theme involved "support systems," with subthemes of "transportation assistance," "financial," and "patient advocacy." Physician factors were also commonly evoked among patients of both races with subthemes of "knowledge", "communication," and "listening." CONCLUSION: PHPT patients cited multiple barriers to undergoing surgery. Future work can focus on examining these questions with a larger patient cohort and examining delays at the referral and diagnosis stage, which was most commonly cited by our respondents.

How often are intrathyroidal parathyroid glands a cause of primary hyperparathyroidism, and how should they be managed?

BACKGROUND: The purpose of our study was to determine the frequency and management of intrathyroidal parathyroid glands in patients with primary hyperparathyroidism and evaluate whether intrathyroidal parathyroid glands were more often superior or inferior glands. METHODS: A retrospective review of the prospective parathyroid database was completed to determine the number of patients with primary hyperparathyroidism and an intrathyroidal parathyroid gland. Demographic data, laboratory and localization studies, operative management, pathology, and outcome were determined for patients with an intrathyroidal parathyroid gland and were compared with patients with an extrathyroidal parathyroid gland. RESULTS: From 1990-2023, 808 patients were operated on for primary hyperparathyroidism; 17 (2%) patients had an intrathyroidal parathyroid gland, an adenoma in 15 (88.2%), and a hyperplastic gland in 2 (11.8%). The mean age was 53 years; 16 (94%) patients were female. Mean calcium and parathyroid hormone was 12 mg/dL and 150 pg/mL, and there were no differences from the extrathyroidal parathyroid group. Ultrasound and Sestamibi imaging were valuable in identifying an intrathyroidal parathyroid gland in 10 of 13 patients and 13 of 17 patients, respectively. Local excision was performed in 9 (53%) patients and lobectomy in 8 (47%) patients. Intraoperative parathyroid hormone was measured and predictive of cure in 12 patients. The location of intrathyroidal parathyroid glands was determined in 15 patients and was inferior in 11 (73%). All patients were cured. No patient developed recurrent disease after a median 54-month follow-up. CONCLUSION: Intrathyroidal parathyroid glands are the cause of primary hyperparathyroidism in 2% of patients and are most often inferior glands. Local excision was accomplished in 53% of our patients.

Association of patient-practitioner sex concordance with specialist referral in primary hyperparathyroidism.

BACKGROUND: Prior research has demonstrated barriers to the workup and management of primary hyperparathyroidism. As recent data have suggested that patient and practitioner sex concordance is associated with lower surgical complications, we sought to evaluate the effect of sex concordance on referral for primary hyperparathyroidism. METHODS: We queried an institutional database for patients with first-incident hypercalcemia and subsequent biochemical evidence of primary hyperparathyroidism between 2010 and 2018. Primary care practitioner and endocrinologist sex, laboratory values, and complications of primary hyperparathyroidism were collected. Sex concordance (male patient/male practitioner or female patient/female practitioner) was evaluated as a binary predictor of specialist evaluation using logistic regression and Cox proportional hazards modeling. RESULTS: Among 1,100 patients, mean age was 62.5 (standard deviation 13.6), and 74% were female sex. Primary care practitioner sex was 52% female, and 63% of patients had sex concordance with their primary care practitioner. Endocrinologist sex was 59% female, and 45% of patients had sex concordance with their endocrinologist. Patients with sex concordance with their primary care practitioner (70 vs 80%, P = .001) and endocrinologist (71 vs 82%, P < .001) were less likely to be female sex compared to those with discordance. After adjusting for demographics and clinical covariates, those patients with primary care practitioner sex concordance had 32% higher odds of endocrinologist evaluation (odds ratio 1.32, 95% confidence interval 1.003-1.734, P = .047). Similarly, those patients with endocrinologist sex concordance had a 48% higher rate of surgeon evaluation (hazard ratio 1.48, confidence interval 1.1-2.0, P = .009). Stratified analysis revealed that sex discordance reduced the rate of surgeon referral for female patients (hazard ratio 0.63, confidence interval 0.44-0.89, P = .008) but not male patients (hazard ratio 1.06, CI 0.58-1.93, P = .861). CONCLUSION: Sex discordance between patients and their health care professionals may contribute to under-referral in primary hyperparathyroidism. Further evaluation of the effect of patient and practitioner identities on communication and decision-making in surgery are needed.

Lithium-associated primary hyperparathyroidism:: An evaluation of screening and referral patterns in a southeastern veteran population.

BACKGROUND: Long-term lithium therapy has a well-established but under-recognized association with primary hyperparathyroidism. Rates of hypercalcemia, screening for primary hyperparathyroidism, and referral for parathyroidectomy were evaluated among United States veterans on long-term lithium therapy. METHODS: Patients undergoing chronic long-term lithium therapy (>12 months) were identified from 1999 to 2022. Demographics, long-term lithium therapy duration, post-treatment calcium, parathyroid hormone, creatinine, and vitamin D levels were abstracted. Rates of screening for hypercalcemia (calcium ≥10.2 mg/dL), primary hyperparathyroidism (parathyroid hormone ≥30 pg/mL in the setting of hypercalcemia), referral for parathyroidectomy, and outcomes were evaluated. RESULTS: A total of 1,356 patients underwent long-term lithium therapy, 514 of whom received chronic long-term lithium therapy. Baseline characteristics of patients with and without post-treatment hypercalcemia were compared. Of 148 patients with post-treatment hypercalcemia, 112 (74.7%) underwent no further evaluation for primary hyperparathyroidism, while 36 (25.3%) patients had a parathyroid hormone level recorded. Although 33 (91.7%) hypercalcemic patients screened positive for primary hyperparathyroidism, only 5 (13%) were referred for parathyroidectomy. Of the 4 patients who underwent parathyroidectomy, mean calcium was 11.2 mg/dL (range 11.1-11.4), and mean parathyroid hormone was 272 pg/mL (range 108-622). Three patients were localized on preoperative imaging, 2 of whom underwent unilateral exploration with cure, with 1 experiencing recurrence at 31 months. The remaining patient who localized preoperatively underwent bilateral exploration and had 2 ipsilateral glands resected and persistence. The patient who did not localize preoperatively underwent bilateral exploration with 3 gland resection and cure. CONCLUSIONS: Screening for primary hyperparathyroidism and referral for parathyroidectomy are underutilized in United States veterans undergoing chronic long-term lithium therapy. Institutional protocols to standardize screening, surveillance, and referrals to endocrinology/endocrine surgery could benefit this population at increased risk for primary hyperparathyroidism.

Social vulnerability and time to surgeon evaluation for primary hyperparathyroidism in a Massachusetts cohort.

BACKGROUND: Identifying patients at risk for under-evaluation of primary hyperparathyroidism is essential to minimizing long-term sequelae, including osteoporosis, nephrolithiasis, and cardiovascular disease. This study assessed the impact of social vulnerability on time-to-surgery evaluation among patients with primary hyperparathyroidism in a Massachusetts cohort. METHODS: This is a retrospective review of patients from an institutional database with the first incident of hypercalcemia between 2010 and 2018 and subsequent biochemical diagnosis of primary hyperparathyroidism. The overall social vulnerability index and social vulnerability index subthemes were merged with the institutional data via patient ZIP code. Patients were stratified into social vulnerability index quartiles, where quartile 4 represented the highest vulnerability. Baseline sociodemographic and clinical characteristics were compared, and Cox regression was used to assess the association between social vulnerability index and time to surgeon evaluation. RESULTS: Of 1,082 patients included, those with a higher social vulnerability index were less likely to be evaluated by a surgeon (quartile 1 social vulnerability index: 31.1% vs. quartile 2 social vulnerability index: 31.41% vs. quartile 3 social vulnerability index: 25.93% vs. quartile 4 social vulnerability index: 21.92%, P = .03). On adjusted analysis, patients with the highest vulnerability had a 33% lower estimated rate of surgeon evaluation and were seen 67 days later compared with patients with the lowest vulnerability (hazard ratio: 0.67, confidence interval 0.47-0.97, P = .032). Differential rates of surgical evaluation by vulnerability persisted for the social vulnerability index subthemes for socioeconomic status, minority status and language, and housing type and transportation. CONCLUSION: Among a Massachusetts cohort, highly vulnerable populations with primary hyperparathyroidism are at greater risk for under-evaluation by a surgeon, which may contribute to the development of long-term sequelae of their disease.

Normocalcemic hyperparathyroidism: Intervention to differentiate primary from secondary hyperparathyroidism.

BACKGROUND: Normocalcemic hyperparathyroidism can occur, but surgery should not be considered until common etiologies for secondary hyperparathyroidism are comprehensively excluded. Calcium deficiency is an underrecognized cause of normocalcemic parathyroid hormone elevation, and we aim to determine if the implementation of a preoperative calcium challenge can be used to reduce unnecessary parathyroidectomy. METHODS: Consecutive patients referred for parathyroidectomy (1/21-6/22) with normocalcemia (serum calcium <10 mg/dL) and concurrently elevated parathyroid hormone levels were routinely treated with supplemental calcium and vitamin D3, and follow-up laboratory studies were assessed. RESULTS: A total of 29/314 (9%) patients had normocalcemic parathyroid hormone elevation with mean calcium, parathyroid hormone, and vitamin D 25OH levels of 9.5 ± 0.3 mg/dL, 109.9 ± 34.9 pg/mL, and 42.7 ± 23.8 ng/mL respectively. Confounding factors included estimated glomerular filtration rate <60 in 2, loop diuretic use in 4, and prior gastric bypass or gastric sleeve surgery in 4. Follow-up biochemical evaluation was available in 27 (92%); results were unchanged in 7 patients (26%); normalization of parathyroid hormone levels with persistently normal calcium levels occurred in 15 (55%), thus confirming secondary hyperparathyroidism and hypercalcemia with elevated parathyroid hormone levels (classic primary hyperparathyroidism) was diagnosed in 5 (19%). Parathyroid exploration has been completed for 3 of 5 patients with classic primary hyperparathyroidism to date. CONCLUSION: A preoperative calcium challenge was prospectively initiated in normocalcemic patients with parathyroid hormone elevation, and there was high compliance (92%). Short-interval calcium supplementation revealed ∼50% to have resolved secondary hyperparathyroidism due to insufficient calcium intake, which avoided unnecessary surgery. In contrast, classic patients were unveiled in 20%, allowing for prompt and correct surgical intervention.

Persistent Primary Hyperparathyroidism Secondary to an Ectopic Mediastinal Adenoma in a Young Adult: A Case Report.

Primary hyperparathyroidism commonly affects elderly women. When present in the young population, it is usually asymptomatic, most frequently due to a parathyroid adenoma and the definitive management is surgical excision. Uncommonly, 5-10% of patients fail to achieve long-term cure after initial parathyroidectomy and 6-16% of them is due to an ectopic parathyroid adenoma that will require focused diagnostic and surgical approaches. We report a 21-year-old male who had bilateral thigh pain. Work-up revealed bilateral femoral fractures, brown tumors on the arms and multiple lytic lesions on the skull. Serum studies showed hypercalcemia (1.83 mmol/L), elevated parathyroid hormone [(PTH) 2025.10 pg/mL], elevated alkaline phosphatase (830 U/L), normal phosphorus (0.92 mmol/L) and low vitamin D levels (18.50 ng/mL). Bone densitometry showed osteoporotic findings. Sestamibi scan showed uptake on the left superior mediastinal region consistent with an ectopic parathyroid adenoma. Vitamin D supplementation was started pre-operatively. Patient underwent parathyroidectomy with neck exploration; however, the pathologic adenoma was not visualized and PTH levels remained elevated post-operatively. Chest computed tomography with intravenous contrast was performed revealing a mediastinal location of the adenoma. A repeat parathyroidectomy was done, with successful identification of the adenoma resulting in a significant drop in PTH and calcium levels. Patient experienced hungry bone syndrome post-operatively and was managed with calcium and magnesium supplementation. A high index of suspicion for an ectopic adenoma is warranted for patients presenting with hypercalcemia and secondary osteoporosis if there is persistent PTH elevation after initial surgical intervention. Adequate follow-up and monitoring is also needed starting immediately in the post-operative period to manage possible complications such as hungry bone syndrome.

GCM2 p.Tyr394Ser variant in Ashkenazi Israeli patients with suspected familial isolated hyperparathyroidism.

Context: A germline mutation can be identified in up to 10% of patients with primary hyperparathyroidism (PHPT). In 2017, a high frequency of the GCM2 [(NM_ 004752.4) c.1181A> C; p.Tyr394Ser; rs142287570] variant was reported in PHPT Ashkenazi Jews (AJ). Objective: To evaluate the presence of the GCM2 p.Tyr394Ser variant in Israeli patients addressed for genetic evaluation to characterize their phenotype and clinical management. Method: Patients with PHPT who underwent addressed for genetic screening for suspected familial hypocalciuric hypercalcemia (FHH), a family history of isolated hyperparathyroidism (FIHP), or failed parathyroidectomy with persistent PHPT were recruited. Those with normal initial selected gene sequencing or hyperparathyroid genetic panel completed the GCM2 p.Tyr394Ser variant sequencing. The prevalence of this variant was evaluated using our local genomic database. Results: A total of 42 single individuals from unrelated kindreds were evaluated. A disease-causing mutation was found in 11 (26.1%) patients: 10 were diagnosed with FHH (eight CASR and two AP2S1 mutations), and one patient had a CKN2B mutation. In 28 of the remaining patients, the GCM2 p.Tyr394Ser variant was positive in three (10.7%), and all were AJ. Within AJ (15/28, 53.5%), the rate of the p.Tyr394Ser variant was 3/15 (20%), and of those, two had a history of familial isolated hyperparathyroidism. Multi-glandular parathyroid adenoma/hyperplasia was also observed in two of these patients. No clinical or laboratory findings could discriminate patients with the GCM2 p.Tyr394Ser variant from those with FHH. Cinacalcet normalized the calcium levels in one patient. The prevalence of the GCM2 p.Tyr394Ser variant in 15,407 tests in our local genomic database was 0.98%. Conclusion: In contrast to previous observations, the GCM2 p.Tyr394Ser variant-associated phenotype may be mild in AJ with FIHP, sometimes mimicking FHH. Because surgery may be curative, surgeons should be aware of the possibility of multiple gland diseases in these patients. The clinical spectrum and clinical utility of screening for this variant warrant further investigation.

Recurrent Primary Hyperparathyroidism in Multiple Endocrine Neoplasia Type 1 Syndrome.

Primary hyperparathyroidism is a common endocrinopathy. Multiple Endocrine Neoplasia Type 1 (MEN1) is a rare autosomal dominantly inherited endocrine tumor predisposition syndrome, with one of main manifestations being primary hyperparathyroidism. We retrospectively evaluated a set of 1011 patients who underwent surgery for primary hyperparathyroidism between the years 2018-2022, and found 78 (8 %) patients who underwent reoperations and 27 patients with MEN1 syndrome. In the group of patients with MEN1 syndrome, 7 (35 %) needed reoperations. Patients with multiple endocrine neoplasia syndrome have a higher risk of needing reoperation. Genetic testing can help identify MEN1 syndrome preoperatively and to better evaluate the approach to surgery.

Molecular Genetic Aspects of Sporadic Multiglandular Primary Hyperparathyroidism.

Multiglandular primary hyperparathyroidism (MGD) represents a rare form of primary hyperparathyroidism (PHPT). MGD is associated with hereditary PHPT, but the sporadic MGD is more common and affects a similar patient profile as single gland parathyroid disease (SGD). The distinction between SGD and MGD is of great clinical importance, especially for the strategy of parathyroidectomy. Based on the limited knowledge available, MGD is likely to be a genetically heterogeneous disease resulting from the interaction of germline and somatic DNA mutations together with epigenetic alterations. Furthermore, these events may combine and occur independently in parathyroid tumors within the same individual with MGD. Gene expression profiling has shown that SGD and MGD may represent distinct entities in parathyroid tumorigenesis. We are waiting for studies to analyze exactly which genes are different in SGD and MGD in order to identify potential biomarkers that can distinguish between the two forms of the disease.