Feasibility of an Online Patient-Driven International Parathyroid Registry.

INTRODUCTION: Traditional parathyroid registries are labor-intensive and do not always capture long-term follow-up data. This study aimed to develop a patient-driven international parathyroid registry and leverage community connections to improve patient-centered care for hyperparathyroidism. METHODS: An anonymous voluntary online survey was developed using Qualtrics and posted in an international patient and advocate-run social media group affiliated with over 11,700 members. The survey was developed from a literature review, expert opinion, and discussion with the social media group managers. It consists of seven sections: patient demographics, past medical history, preoperative symptoms, laboratory evaluation, preoperative imaging studies, operative findings, and operative outcomes. RESULTS: From July 30, 2022, to October 1, 2022, 89 complete responses were received. Participants were from 12 countries, mostly (82.0%) from the United States across 31 states. Most participants were female (91.4%), White (96.7%) with a mean (±standard deviation) age of 58 ± 12 y. The most common preoperative symptoms were bone or joint pain (84.3%) and neuropsychiatric symptoms: including fatigue (82.0%), brain fog (79.8%), memory loss (79.8%), and difficulty with concentration (75.3%). The median (interquartile range) length from symptom onset to diagnosis was 40.0 (6.8-100.5) mo. Seventy-one percent of participants had elevated preoperative serum calcium, and 73.2% had elevated preoperative parathyroid hormone. All participants obtained preoperative imaging studies (88.4% ultrasound, 86.0% sestabimi scan, and 45.3% computed tomography). Among them, 48.8% of participants received two, and 34.9% had three imaging studies. The median (interquartile range) time from diagnosis to surgical intervention was 3 (2-9) mo. Twenty-two percent of participants traveled to different cities for surgical intervention. Forty-seven percent of participants underwent outpatient parathyroidectomy. Eighty-four percent of participants reported improved symptoms after parathyroidectomy, 12.4% required oral calcium supplementation for more than 6 mo, 32.6% experienced transient hoarseness after parathyroidectomy, and 14.6% required reoperation after initial parathyroidectomy. CONCLUSIONS: This international online parathyroid registry provides a valuable collection of patient-entered clinical outcomes. The high number of responses over 10 wk demonstrates that participants were willing to be involved in research on their disease. The creation of this registry allows global participation and is feasible for future studies in hyperparathyroidism.

Predictive factors for persistent hypercalcemia following parathyroidectomy in patients with persistent hyperparathyroidism after kidney transplantation: a retrospective cohort study.

BACKGROUND: Surgery for irreversible hyperparathyroidism is the preferred management for kidney transplant patients. The authors analyzed the factors associated with persistent hypercalcemia after parathyroidectomy in kidney transplant patients and evaluated the appropriate extent of surgery. MATERIALS AND METHODS: The authors retrospectively analyzed 100 patients who underwent parathyroidectomy because of persistent hyperparathyroidism after kidney transplantation at a tertiary medical center between June 2011 and February 2022. Patients were divided into two groups: 22 with persistent hypercalcemia after parathyroidectomy and 78 who achieved normocalcemia after parathyroidectomy. Persistent hypercalcemia was defined as having sustained hypercalcemia (≥10.3 mg/dl) 6 months after kidney transplantation. The authors compared the biochemical and clinicopathological features between the two groups. Multivariate logistic regression analysis was used to identify potential risk factors associated with persistent hypercalcemia following parathyroidectomy. RESULTS: The proportion of patients with serum intact parathyroid hormone (PTH) level is greater than 65 pg/ml was significantly high in the hypercalcemia group (40.9 vs. 7.7%). The proportion of patients who underwent less than subtotal parathyroidectomy was significantly high in the persistent hypercalcemia group (17.9 vs. 54.5%). Patients with a large remaining size of the preserved parathyroid gland (≥0.8 cm) had a high incidence of persistent hypercalcemia (29.7 vs. 52.6%). In the multivariate logistic regression analysis, the drop rate of intact PTH is less than 88% on postoperative day 1 (odds ratio 10.3, 95% CI: 2.7-39.1, P =0.001) and the removal of less than or equal to 2 parathyroid glands (odds ratio 6.8, 95% CI: 1.8-26.7, P =0.001) were identified as risk factors for persistent hypercalcemia. CONCLUSION: The drop rate of intact PTH is less than 88% on postoperative day 1 and appropriate extent of surgery for controlling the autonomic function were independently associated with persistent hypercalcemia. Confirmation of parathyroid lesions through frozen section biopsy or intraoperative PTH monitoring can be helpful in preventing the inadvertent removal of a parathyroid gland and achieving normocalcemia after parathyroidectomy.

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.

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.

Role of hospital and patient factors in the outcome of reoperations for primary hyperparathyroidism: a retrospective multicenter cohort study.

BACKGROUND: There are few data on outcomes after reintervention for persistent or recurrent primary hyperparathyroidism (PHPT). The authors hypothesized that the variation in outcomes at the hospital level after reoperation would be significant. After accounting for this variability, some patient-level clinical criteria could be identified to help inform treatment decisions in this patient population. The aim of this study was to determine whether there is significant variation in outcomes after reoperation for PHPT between hospitals (hospital-level analysis) and identify clinical factors (patient-level analysis) that influence postoperative outcomes. MATERIALS AND METHODS: This retrospective multicenter cohort study was performed using the Eurocrine registry. Data from 11 countries and 76 hospitals from January 2015 to October 2020 were extracted. A generalized linear mixed model was used to assess the variation in outcomes at the hospital level and to identify risk factors of postoperative outcomes at the patient level. The primary endpoint (textbook outcome) was achieved when all six of the following postoperative conditions were met: no hypocalcemia or persistent hypercalcemia, no laryngeal nerve injury, no negative exploration, no normal parathyroid gland only on histopathology, and no postoperative death. RESULTS: Among 13 593 patients who underwent parathyroidectomy for PHPT, 617 (4.5%) underwent reoperative parathyroidectomy. At follow-up, 231 patients (37.4%) were hypocalcemic, 346 (56.1%) were normocalcemic without treatment, and 40 (6.5%) had persistent hypercalcemia. Textbook outcomes were achieved in 321 (52.0%) patients. The hospital-level variation in textbook outcome rates was significant ( P <0.001), and this variation could explain 29.1% of the observed outcomes. The criterion that remained significant after controlling for inter-hospital variation was 'a single lesion on sestamibi scan or positron emission tomography (PET) imaging' (odds ratio 2.08, 95% confidence interval 1.24-3.48; P =0.005). CONCLUSION: Outcomes after reoperation are significantly associated with hospital-related factors. A 'single lesion observed on preoperative sestamibi scan or PET' appears relevant to select patients before reoperation.

Persistence and Recurrence of Hypercalcemia After Parathyroidectomy Over 5 Decades (1965-2010) in a Community-based Cohort.

BACKGROUND: There is limited long-term follow-up of patients undergoing parathyroidectomy. Recurrence is described as 4% to 10%. This study evaluated persistence and recurrence of hypercalcemia in primary hyperparathyroidism after parathyroidectomy. METHODS: Single-institution retrospective (1965-2010) population-based cohort from Olmsted County (MN) of patients undergoing surgery for primary hyperparathyroidism. Patients' demographic data, preoperative and postoperative laboratory values, clinical characteristics, surgical treatment, and follow-up were noted. RESULTS: A total of 345 patients were identified, 75.7% female, and median age 58.4 years [interquartile range (IQR): 17.6]. In all, 68% of patients were asymptomatic and the most common symptoms were musculoskeletal complaints (28.4%) and nephrolithiasis (25.6%). Preoperative median serum calcium was 11 mg/dL (IQR: 10.8-11.4 mg/dL), and median parathyroid hormone was 90 pg/mL (IQR: 61-169 pg/dL). Bilateral cervical exploration was performed in 38% and single gland resection in 79% of cases. Median postoperative serum calcium was 9.2 mg/dL (IQR: 5.5-11.3). Nine percent of patients presented persistence of hypercalcemia, and recurrence was found in 14% of patients. Highest postoperative median serum calcium was 10 mg/dL (IQR: 6-12.4), and median number of postoperative calcium measurements was 10 (IQR: 0-102). Postoperative hypercalcemia was identified in 37% of patient. Fifty-three percent were attributed to secondary causes, most commonly medications, 22%. Three percent of patients required treatment for postoperative hypercalcemia. Median time to recurrence and death were 12.2 and 16.7 years, respectively. CONCLUSION: Recurrent hypercalcemia after successful parathyroidectomy is higher than previously reported. Most cases are transient and often associated to other factors with only the minority requiring treatment. Long-term follow-up of serum calcium should be considered in patients after successful parathyroidectomy.

Surgical description and outcome of ultrasound-guided minimally invasive parathyroidectomy in 50 dogs with primary hyperparathyroidism.

OBJECTIVE: To describe the surgical technique and clinical outcome of minimally invasive parathyroidectomy for primary hyperparathyroidism (PHPT) in the dog. ANIMALS: Fifty client-owned dogs with PHPT that underwent minimally invasive parathyroidectomy. STUDY DESIGN: Retrospective cohort study. METHODS: An ultrasound-guided mini lateral approach was made via a plane established between the sternocephalicus muscle and sternohyoideus muscles to expose the thyroid gland and enlarged parathyroid gland. Abnormal parathyroid glands were removed en bloc via partial thyroidectomy. The technique for bilateral disease was similar, the skin incision was made on midline and moved laterally to develop the above-mentioned plane of dissection. Age, sex, breed, bodyweight, ultrasound findings, histopathological diagnosis, surgical time, preoperative clinical signs, and clinical outcome were extracted from the records for descriptive statistics. RESULTS: A total of 62 glands were surgically removed, including 17 hyperplastic glands (17/62, 27.4%), 34 adenomas (34/62, 54.8%), and two carcinomas (2/62, 3.2%). Hypercalcemia resolved shortly after surgery in 44 dogs (44/45, 97.8%). One dog had recurrent hypercalcemia (1/45, 2.2%), one dog had persistent hypercalcemia (1/45, 2.2%), two dogs had permanent hypocalcemia requiring life-long calcitriol supplementation (2/45, 4.4%), and one dog died from clinical hypocalcemia (1/45, 2.2%). CONCLUSION: Minimally invasive parathyroidectomy was associated with a low morbidity and led to favorable outcomes in 44/45 dogs in this series. CLINICAL SIGNIFICANCE: The results of this study supports the use of minimally invasive parathyroidectomy to treat PHPT in dogs.

Effects of primary hyperparathyroidism on oral health. A longitudinal register-based study.

OBJECTIVES: To analyze the effects of primary hyperparathyroidism on oral health and to investigate if the effects are linked to severity of the disease. SUBJECTS AND METHODS: This prospective cohort study involved 6151 primary hyperparathyroidism patients registered in the Scandinavian Quality Registry of Thyroid, Parathyroid, and Adrenal surgery and the National Cancer Register after parathyroidectomy (exposure) during 2011-2017 (patient cohort) and 60,654 individuals without primary hyperparathyroidism (reference cohort), matched by age, gender, and county of resident at the date of parathyroidectomy. The outcomes were tooth extractions and periodontal interventions. The risk for the outcomes was assessed by Poisson regression models. RESULTS: After adjusting for covariates, the patient cohort had a higher incidence rate of tooth extraction during the two-year period after parathyroidectomy (IRR = 1.15; 95% CI = 1.01-1.31), but a lower incidence rate of periodontal interventions during the four- to six-year period after parathyroidectomy (IRR = 0.88; 95% CI = 0.79-0.99). Furthermore, patients with more severe primary hyperparathyroidism were more likely to have tooth extractions and periodontal interventions after parathyroidectomy. CONCLUSIONS: The risk of tooth extraction increased slightly during the first two years after parathyroidectomy. Thereafter, the oral health effects subsided. Pre-surgical serum ionized calcium levels and adenoma weight may indicate negative dental outcomes after parathyroidectomy.

What happens to the bone structure after normocalcemic primary hyperparathyroidism surgery?

BACKGROUND: Bone disease in primary hyperparathyroidism is a clear indication for surgical treatment. However, it is not known whether surgery benefits hypercalcemic primary hyperparathyroidism and normocalcemic primary hyperparathyroidism equally. The aim of our study was to evaluate the bone changes in patients undergoing parathyroidectomy based on the biochemical profile 1 and 2 years after surgery. METHODS: This prospective study included 87 consecutive patients diagnosed with primary hyperparathyroidism who underwent surgery between 2016 and 2018. Bone densitometry (1/3 distal radius, lumbar, and femur) and bone remodeling markers (osteocalcin, type 1 procollagen [P1NP], ß-cross-linked telopeptide of type I collagen [BCTX]) were performed preoperatively and postoperatively. Postoperative changes in bone mineral density and bone markers were compared and evaluated according to the clinical characteristics and the individual biochemical profile. RESULTS: One year after surgery, all patients showed an increase in bone mineral density at the lumbar site (mean, 0.029 g/cm2; range, 0.017-0.04; P < .001) and femur neck (mean, 0.025 g/cm2; range, 0.002-0.05; P < .001); however, there were no changes in the distal third of the radius (mean, -0.003 g/cm2; range, -0.008 to 0.002; P = NS). There were no significant differences when comparing normocalcemic primary hyperparathyroidism and hypercalcemic primary hyperparathyroidism. Serum osteocalcin (37 ± 17.41), P1NP (67.53 ± 31.81) and BCTX (0.64 ± 0.37) levels were elevated before surgery. One year after the surgery, we observed a significant decrease in P1NP (33.05 ± 13.16, P = .001), osteocalcin (15.80 ± 6.19, P = .001), and BCTX (0.26 ± 0.32, P < .001) levels. CONCLUSION: Our findings indicate that parathyroidectomy has similar benefits for normocalcemic primary hyperparathyroidism and hypercalcemic primary hyperparathyroidism in terms of bone improvement. Although the most substantial improvement occurred during the first postoperative year in both groups, we consider that studies with longer follow-up are warranted.

How and when is multiglandular disease diagnosed in sporadic primary hyperparathyroidism?

BACKGROUND: In total, ∼15% of patients with sporadic primary hyperparathyroidism have multiglandular disease, which may be suspected preoperatively but can only be confirmed intra or postoperatively. The study aim is to determine how and when patients are diagnosed with multiglandular disease and to what extent different modalities contribute. METHODS: Consecutive cases of sporadic primary hyperparathyroidism (2013-2019) undergoing initial exploration were reviewed from a single-institution prospective database. Preoperative single-photon emission tomography/computed tomography and neck ultrasound were routinely performed to help direct either bilateral or unilateral exploration guided by intraoperative parathyroid hormone monitoring using the dual criteria. Multiglandular disease was defined as either resection of >1 enlarged parathyroid or hypercalcemia at ≥6 months after single gland resection. RESULTS: Of 1,890 patients with sporadic primary hyperparathyroidism, multiglandular disease was identified in 254 (13.4%); 244 (96.1%) were diagnosed intraoperatively and 10 (3.9%) postoperatively. In these multiglandular disease patients, single gland disease was suggested on single-photon emission tomography/computed tomography in 54.0%, ultrasound in 49.2%, and both were concordant for single gland disease in 29.4%. Intraoperative multiglandular disease diagnosis was prompted by an inadequate intraoperative parathyroid hormone monitoring drop in 38.5%, by surgeon interpretation of imaging in 38.1%, by observing ipsilateral gland enlargement in 11.0%, by finding an initial gland <200 mg in 10.3%, and 2.0% had unexpected multiglandular disease during thyroidectomy. Multiglandular disease was diagnosed by postoperative hypercalcemia in 10 of 254 patients (4.9%). CONCLUSION: To avoid failure at parathyroidectomy for primary hyperparathyroidism, expert surgeons use multiple approaches to diagnose and manage multiglandular disease. Preoperative localization studies alone are insufficient, missing multiglandular disease in at least 30% of cases. All examined adjuncts are informative, including intraoperative parathyroid hormone monitoring, imaging, and intraoperative visual cues.

Stones left unturned: Missed opportunities to diagnose primary hyperparathyroidism in patients with nephrolithiasis.

BACKGROUND: Nephrolithiasis is a sequela of primary hyperparathyroidism and an indication for parathyroidectomy. The prevalence of primary hyperparathyroidism in patients with nephrolithiasis is 3% to 5%; however, recent studies suggest that many hypercalcemic patients with nephrolithiasis never undergo workup for primary hyperparathyroidism. Our goal is to evaluate primary hyperparathyroidism screening rates at a tertiary academic health institution and identify opportunities to increase referral rates in patients presenting with nephrolithiasis. METHODS: We retrospectively reviewed 15,725 patients across an academic health system who presented with nephrolithiasis between 2012 and 2020. Calcium levels measured within 6 months of presentation were identified, and those with hypercalcemia (≥10.3 mg/dL) were reviewed if parathyroid hormone levels were measured. Patients with primary hyperparathyroidism were evaluated to see if they were referred to a specialist for treatment. RESULTS: Of 15,725 patients presenting with nephrolithiasis, 12,420 (79%) had calcium levels measured; 630 patients (4.0%) were hypercalcemic, and 207 (33%) had parathyroid hormone levels measured. Patients were more likely to have parathyroid hormone levels sent if they were older, had higher calcium levels, or presented to an outpatient clinic (P = .028, P = .002, P < .001). We identified 89 patients (0.6%) with primary hyperparathyroidism, of which only 35 (39%) were referred for treatment. CONCLUSION: The proportion of patients presenting with nephrolithiasis ultimately diagnosed with primary hyperparathyroidism was significantly lower than others have reported. Additionally, a substantial number of patients with nephrolithiasis did not have calcium and/or parathyroid hormone levels measured. These missed opportunities for diagnosis are critical as early definitive management of primary hyperparathyroidism can prevent recurrent nephrolithiasis and other primary hyperparathyroidism-related end organ effects.

Recurrence after successful parathyroidectomy-Who should we worry about?

BACKGROUND: Preventing cervical reoperations is important-especially after parathyroidectomy. We sought to examine early predictors of recurrence of primary hyperparathyroidism after surgical cure. METHODS: Adult patients with sporadic primary hyperparathyroidism treated with parathyroidectomy between September 1, 1997, and September 1, 2019, with confirmed eucalcemia at 6 months postoperatively were identified. Recurrence was defined as hypercalcemia (>10.2 mg/dL) with an elevated or nonsuppressed parathyroid hormone level on subsequent follow-up. RESULTS: Parathyroidectomy was performed in 522 patients (median age, 62.1 years, 77% female) with the majority undergoing planned minimally invasive parathyroidectomy (85.4%, n = 446). After a median follow-up of 30.9 months, 13 patients (2.5%) recurred (median time to recurrence 50.2 months, interquartile range 27.9-66.5), all of whom underwent planned minimally invasive parathyroidectomy (n = 13/446, 2.9%). Recurrence was more common in those with higher (but still normal) 6-month calcium (10.1 vs 9.3 mg/dL, P < .001) or parathyroid hormone values (64 vs 46 pg/mL, P < .01). Multivariate analysis revealed that age >66.5 years, calcium ≥9.8mg/dL and parathyroid hormone ≥80 pg/mL at 6 months were associated with increased risk of recurrence. In addition, the presence of at least 1 preoperative imaging study that conflicted with intraoperative findings among minimally invasive parathyroidectomy patients (n = 446) was associated with increased risk of recurrence (hazard ratio 4.93, 95% confidence interval 1.25-16.53, P = .016). CONCLUSION: Recurrence of sporadic primary hyperparathyroidism after initial surgical cure in the era of minimally invasive parathyroidectomy is 2.5%. Identification of those at risk for recurrence using 6-month serum calcium ≥9.8 mg/dL, parathyroid hormone ≥80 pg/mL, and/or potentially conflicting localization studies may inform surveillance strategies.

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

BACKGROUND: Although the inverse correlation between serum PTH and phosphate (P) levels in patients with primary hyperparathyroidism (PHPT) is well known, the relationship between P levels and the clinical picture of the disease has not been well investigated. This was thus the aim of this paper. PATIENTS: A total of 472 consecutive patients with PHPT attending our center were retrospectively evaluated at diagnosis. RESULTS: P levels lower than 2.5 mg/dL (HypoP) were found in 198/472 patients (41.9%). HypoP was mild (2-2.5 mg/dL), moderate (1-1.9 mg/dL), and severe (<1 mg/dL) in 168 (84.9%), 30 (15.1%), and 0 cases, respectively. P levels were lower in males than females. Patients with more severe bone density impairment at the radial (but not the vertebral or femoral) site had P levels significantly lower than other patients. PHPT severity was worse in HypoP patients, both clinically (higher prevalence of renal stones, but not of osteoporosis) and biochemically (higher serum calcium and PTH levels). All patients in the moderate HypoP group were either symptomatic or asymptomatic reaching surgical indication according to the latest guidelines. CONCLUSIONS: We observed a relationship between P levels and biochemical and clinical features of PHPT severity. In asymptomatic PHPT patients, even moderate HypoP is predictive of surgical indication, regardless of age and hypercalcemia severity.

Metastatic parathyroid cancer: a rare cause of hypercalcaemia.

A 45-year-old man presenting with abdominal pain was found to have severe hypercalcaemia with elevated parathyroid hormone. Investigations revealed a parathyroid mass and bone metastases consistent with metastatic parathyroid carcinoma. The patient underwent parathyroidectomy, with histology confirming a right inferior parathyroid carcinoma. His postoperative management was complicated by severe hypercalcaemia refractory to medical therapy, owing to the metastases continuing to produce parathyroid hormone. Despite palliative radiotherapy to the metastases, the patient died within 3 months from end-organ failure related to hypercalcaemia.

Primary hyperparathyroidism presenting as a brown tumor with hypercalcemia crisis in a second-trimester pregnant woman: A case report.

INTRODUCTION: Primary hyperparathyroidism (PHPT) in pregnancy is rare and unrecognized because the maternal physiological adaptations blurs the symptoms. There is no standard treatment strategy for maternal PHPT. Early diagnosis and interventions can prevent catastrophic consequences to the mother and fetus. PATIENT CONCERNS: A 31-year-old Chinese woman was admitted, due to a lump on the left lower leg for 4 months. The patient complained of mild pain in the left lower leg following exercise that could be relieved after a short rest. The patient was at 18 weeks of gestation, and the growth of the fetus was normal. The patient has a 3-year history of hypercalcemia and a 2-year history of nephrolithiasis. No family history of hypercalcemia and endocrine tumors were present. DIAGNOSIS: Laboratory tests demonstrated high serum calcium level of 3.84 mmol/L, parathyroid hormone 1393 pg/mL, alkaline phosphatase 488 µ/L. Ultrasound showed a 22.4 mm × 7.8 mm solid nodule in the left lower lobe of the thyroid gland. Based on these findings, the patient was diagnosed with PHPT. INTERVENTIONS: The patient accepted continuous renal replacement to reduce ironized calcium level. Parathyroidectomy was performed at the 19th week of gestation. Threatened abortion occurred 2 days after the surgery, and magnesium sulfate was used to prevent the abortion. Calcium gluconate, calcium carbonate and vitamin D3 were used to treat the hypocalcemia that occurred 5 days after the surgery. OUTCOMES: Pathology examination demonstrated the parathyroid adenoma. Abortion was prevented using magnesium sulfate and hypocalcemia was cured with calcium gluconate, calcium carbonate and vitamin D3. At 38-week of gestation, the patient (ionized calcium level: 2.16 mmol/L) delivered a healthy female baby weighing 2700 g with 10/10 Apgar. Till now, both the mother and infant showed no complications. CONCLUSION: Maternal PHPT is rare and challenging to diagnose, causing life-threatening complications to mother and fetus. Any decision regarding surgery for a pregnant woman with primary hyperparathyroidism is more complex than in men or nonpregnant women. The decision should be made based on the severity of hypercalcemia and symptoms.

Radiofrequency Ablation of Parathyroid Glands to Treat a Patient With Hypercalcemia Caused by a Novel Inactivating Mutation in CaSR.

Objective: We identified a novel inactivating mutation in the calcium-sensing receptor (CaSR) gene in a patient with refractory hypocalciuric hypercalcemia and analyzed its function. The effectiveness of radiofrequency ablation of the parathyroid glands to treat hypercalcemia caused by this mutation was explored. Methods: Clinical data of patients before and after radiofrequency ablation were retrospectively analyzed. The CaSR mutation (D99N) found in the patient was studied in cell lines. HEK-293 cells were transfected with plasmids containing wild-type (WT) or mutant CaSR genes (D99N and W718X). Expression levels of the respective CaSR proteins were measured, and their functions were assessed by examining the effect of NPS R-568 (a CaSR agonist) on intracellular Ca2+ oscillations and that of exogenous parathyroid hormone (PTH) on intracellular cyclic adenosine monophosphate (cAMP) levels. Results: The effectiveness of pharmacological treatment was poor, whereas radiofrequency ablation of the parathyroid glands resulted in controlled blood calcium and PTH levels in the patient. In cell lines, upon NPS R-568 administration, the amplitude of intracellular Ca2+ oscillations in the D99N group was lower than that in the WT group and higher than that in the W718X group. Upon administration of PTH, intracellular cAMP levels in the D99N group were higher than those in the WT group and lower than those in the W718X group. Conclusion: The homozygous mutation D99N reduced CaSR activity and caused more severe hypocalciuric hypercalcemia. For patients with this type of hypercalcemia and poor response to pharmacological treatments, radiofrequency ablation of the parathyroid glands may be a suitable treatment option.

Urinary calcium indices in primary hyperparathyroidism (PHPT) and familial hypocalciuric hypercalcaemia (FHH): which test performs best?

AIM: Primary hyperparathyroidism (PHPT) is much more common than familial hypocalciuric hypercalcaemia (FHH), but there is considerable overlap in biochemical features. Urine calcium indices help with the differential diagnosis, but their reliability in making this distinction is not clear. The aim of this study was to compare urinary calcium values in patients with PHPT and FHH. METHODS: This was a case-control study of patients with PHPT who had successful surgery and genetically proven FHH between 2011 and 2016. Due to low FHH numbers, patients from neighbouring hospitals and outside study period (2017-2019) were allowed to improve power. Data on demographics and urinary calcium were obtained from electronic records and compared between the two groups. RESULTS: During the study period, 250 patients underwent successful PHPT surgery, while in the FHH arm, 19 genetically proven cases were included. The median (IQR) 24-hour urine calcium excretion (UCE) in the PHPT group was 8.3 (5.6-11.2) mmol/24 hours compared with 3.2 (2.1-6.1) mmol/24 hour in the FHH group (p<0.001). Median (IQR) calcium to creatinine clearance ratio (CCCR) in the PHPT and FHH groups was 0.020 (0.013-0.026) and 0.01 (0.002-0.02), respectively (p=0.001). The sensitivity of urinary tests for PHPT was 96% for UCE (cut-off ≥2.5 mmol/24 hour) and 47% for CCCR (cut-off >0.02). The specificity of the urinary tests for FHH was 29.4% for UCE (cut-off <2.5 mmol/24 hour) and 93% for CCCR (cut-off <0.02). CONCLUSIONS: 24-hour UCE is more sensitive in diagnosing PHPT; however, it is less specific in ruling out FHH as compared with CCCR, when the cut-offs suggested by the International guidelines from the fourth international workshop are used. A significant proportion of patients with PHPT would have also required genetic studies if the guidelines were followed.