Effect of vitamin D nutrition on parathyroid adenoma weight: pathogenetic and clinical implications

Calcium/phosphate ratio: an additional tool for the clinical management of asymptomatic primary hyperparathyroidism?

PURPOSE

Serum calcium/phosphate ratio (Ca/P) has been recently proposed as an additional tool to identify primary hyperparathyroidism (PHPT), especially in patients with subclinical presentation, with a proposed cut-off of 3.3 when both values are expressed in mg/dL. No data are available on the relationship between Ca/P and the clinical presentation of PHPT. We thus evaluated this relationship in a large, single-center, unselected series.

METHODS

515 consecutive PHPT patients (mean age 65 ± 13.15 years, 77.1% females) were retrospectively evaluated at diagnosis.

RESULTS

Mean Ca/P was 4.54 ± 1.5 (range 2.36-13.9), being higher than 3.3 in 88.5% of patients. Ca/P was significantly higher in (1) males, (2) symptomatic PHPT, (3) patients with 25-hydroxy vitamin D levels lower than 20 μg/L, (4) patients with osteitis fibrosa cystica, (5) patients with T score < - 2.5 at the radial site. In a multivariate regression analysis, Ca/P resulted significantly associated with PTH levels. After the exclusion of 57 patients with asymptomatic PHPT (aPHPT) patients and serum Ca higher than 1 mg/dL above the upper limit of normal range, no differences were found in Ca/P between aPHPT meeting or not surgical criteria.

CONCLUSIONS

In PHPT Ca/P ratio is associated with increased biochemical and clinical severity of disease and represents a direct indicator of clinical bone damage. However, it does not seem an additional tool to identify aPHPT patients reaching surgical indication.

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.

A Significant Association between Parathyroid Adenoma Volume and Bone Mineral Loss at Distal Forearm

INTRODUCTION

The cortical bone is the most severely affected site in patients with primary hyperparathyroidism (PHPT) and thus, a low bone mineral density (BMD) is predominantly observed in distal forearm. Several studies have investigated potential associations between the weight of the gland and bone mineral loss. In this study, we wanted to investigate the relationship between parathyroid adenoma (PTA) volume and bone mineral loss.

METHODS

All patients with a diagnosis of PHPT who were operated at our hospital, and with a histologically proven single PTA were retrospectively analyzed. Z-scores were used as the main variable in our analysis to eliminate the effects of age, sex and gonadal status on BMD.

RESULTS

Total of 153 patients who met the inclusion criteria were eligible for the study. A significant negative correlation between the PTA volume and z-score for distal third of the radius (DR) (p = 0.006, r = -0.297) was shown. The cut-off value of gland volume for predicting cortical bone mineral loss was 9043.2 mm3. There was also a significant negative correlation between the 24-hour urine calcium and z-scores for lumbar vertebrae and total hip. A significant negative correlation was found between preoperative 25-hydroxy vitamin D levels and the PTA weight.

CONCLUSIONS

As the first study that evaluated any possible association between the volume of a parathyroid adenoma and bone mineral loss in patients with PHPT, we found a significant negative correlation between DR z-scores and resected gland volume. Since the volume of a PTA can also be determined by a preoperative US, our findings may be helpful during the preoperative evaluation of a patient with a preliminary diagnosis of PHPT.

Differences in the Clinical Presentation and Biochemical Profile of the Patients with Primary Hyperparathyroidism with regard to their Serum Vitamin D Levels: a Single-center Experience

The association between vitamin D deficiency and primary hyperparathyroidism (PHPT) is common and has clear implications. Vitamin D deficiency is commonly seen in PHPT population and exacerbates its severity with skeletal and metabolic effects. Retrospective data collection and review were done in patients who underwent surgery for PHPT at a tertiary care hospital in India between January 2011 and December 2020. A total of 150 subjects were included in the study and were divided into group 1 (vitamin D < 20 ng/ml, deficient), group 2 (vitamin D 21-29 ng/ml, insufficient), and group 3 (vitamin D > 30 ng/ml, sufficient). There was no difference in the duration of symptoms or the symptomatology between the three groups. Mean pre-operative serum calcium and serum phosphorous levels were also comparable in all the three groups. Mean pre-operative parathyroid hormone (PTH) levels in the three groups were 703 ± 996 vs 343.6 ± 396 vs 343.6 ± 396 pg/ml, respectively (P = 0.009). There was a statistically significant difference in group 1 vs groups 2 and 3 in their mean weight of the parathyroid gland (P = 0.018) and high alkaline phosphatase (ALP) levels (P = 0.047). Post-operative symptomatic hypocalcemia was observed in 17.3% of patients. Post-operative hungry bone syndrome occurred in 4 patients, all in group 1. PHPT in patients with low serum vitamin D was associated with higher serum PTH levels, increased frequency of high serum ALP levels, and higher weight of the excised gland, with no difference in the serum calcium and phosphorous.

Revisiting Captain Charles Martell: witnessing the true face of primary hyperparathyroidism even in the twenty-first century

BACKGROUND

Severe presentation of primary hyperparathyroidism (PHPT) which, although, common in the Asian population, is albeit rarely encountered in the present era.

CASE PRESENTATION

We present a 23-year-old lady whose symptoms began in 2016 with generalized body aches. Subsequently, her husband noticed a reduction in her height and she developed gradual protrusion of chest. Meanwhile, she conceived in November 2019 and delivered a full-term healthy baby girl. She breastfed her baby for 18 months during which her symptoms worsened. On examination, she measured only 123 cm, having lost nearly 23 cm in height. She had a short neck, pectus carinatum-like deformity of chest, protruded abdomen, kyphosis, and scoliosis. Investigations revealed PTH-dependent hypercalcemia, diffuse cortical thinning, brown tumors, codfish vertebrae, and bilateral nephrolithiasis. A diagnosis of primary hyperparathyroidism (PHPT) was made with the grave clinical picture bearing a striking resemblance to that of Captain Charles Martell, the first ever recorded case of PHPT in the world.

CONCLUSION

The index case highlights the fact that PHPT, if left undiagnosed and untreated, can have debilitating consequences. A high index of suspicion should be exercised while evaluating all suspected cases of metabolic bone disorders and being the third most common endocrine disorder, the possibility of PHPT should be entertained wherever appropriate.

Effect of Parathyroidectomy on Metabolic Homeostasis in Primary Hyperparathyroidism

Background: The benefits of parathyroidectomy on cardiovascular risk in primary hyperparathyroidism (PHPT) are controversial. This monocentric, observational, prospective study aimed to assess the effects of parathyroidectomy on glucose and lipid metabolism in classic or mild PHPT. Methods: Patients who underwent parathyroidectomy for classic (calcemia >2.85 mmol/L) or mild PHPT (calcemia ≤2.85 mmol/L) between 2016 and 2019 were included. A metabolic assessment was performed before and 1 year after parathyroidectomy. Patients with a history of diabetes were excluded. Results: Nineteen patients had classic and 120 had mild PHPT. Ninety-five percent were normocalcemic 6 months after surgery. Fasting plasma glucose and insulin levels decreased after parathyroidectomy in patients with mild PHPT (p < 0.001). HOMA-IR decreased after surgery in the overall population (p < 0.001), while plasma adiponectin concentrations increased in patients with both classic (p = 0.005) and mild PHPT (p < 0.001). Plasma triglyceride levels decreased significantly only in patients with classic PHPT (p = 0.021). Plasma PCSK9 levels decreased in patients with mild PHPT (p < 0.001). Conclusions: Parathyroidectomy for PHPT improves insulin resistance and decreases plasma triglyceride levels in classic PHPT and plasma PCSK9 levels in mild PHPT. Further studies are needed to better characterize the consequences of such metabolic risk factors’ improvements on cardiovascular events.

Reduction in parathyroid adenomas by cinacalcet therapy in patients with primary hyperparathyroidism

INTRODUCTION

Cinacalcet is a calcimimetic that modulates the functions of calcium-sensing receptor and is currently used to treat patients with primary hyperparathyroidism (PHPT). Although it was reported that cinacalcet treatment reduced the size of hyperplastic parathyroid glands in patients with secondary hyperparathyroidism, whether or not cinacalcet treatment can reduce the size of parathyroid adenomas in patients with PHPT has been unknown.

MATERIALS AND METHODS

We recruited nine (male: one, female: eight) patients with PHPT due to parathyroid adenomas who did not undergo parathyroidectomy. Cinacalcet was administered at a dose of 50 mg/day, and we evaluated the size of parathyroid adenomas (width × thickness) (mm²) using ultrasonography before and after 6 months of cinacalcet treatment.

RESULTS

The mean age of the subjects was 58.1 ± 7.2 years old, and the mean serum intact parathyroid hormone (PTH) concentration was 134.8 ± 8.7 pg/ml. All participants showed hypercalcemia and osteopenia. After 6 months, the mean size of parathyroid adenomas was significantly decreased (baseline: 73.8 ± 33.4 mm² vs. after 6 months: 52.5 ± 25.0 mm², p = 0.045). Thus, 6-month cinacalcet treatment induced a 29% size reduction in parathyroid adenomas. Furthermore, the serum intact PTH concentration before cinacalcet treatment was positively correlated with the reduction in the size of parathyroid adenomas.

CONCLUSION

The present study revealed that cinacalcet treatment reduces the size of parathyroid adenomas in patients with PHPT. The accumulation of more PHPT cases with cinacalcet therapy is required to confirm this finding.

Giant versus regular parathyroid adenoma: A retrospective comparative study

Background

A fraction of Parathyroid Adenoma (PTA) is considered giant if they weigh more than 3.5 g. There is no clear consensus whether this subgroup has a distinct clinical or biochemical presentation that could have implications on PTA localization and management. In this study, we investigate the difference between regular and giant PTA patients regarding their clinical and laboratory findings as well as their postoperative outcomes.

Materials and methods

Clinical and PTA-related data were retrospectively retrieved from all patients undergoing parathyroidectomy from 2010 to 2019 at our hospital.

Results

A total number of 84 PTA (Females 76.2%) patients were included, of which 24 (28.6%) qualified as a giant with a mean weight of 7.86 g and the rest were regular adenomas (71.4%) with a mean weight of 1.45 g. Giant adenomas were more likely to present at a younger age compared to regular adenoma patients, (44.4 vs 50.8, P = 0.053, D = 0.470). Preoperative PTH levels were significantly higher in the giant PTA group (650.8 vs 334.2 pg/mL, P = 0.044, r = 0.22). Hospital stay was on average 1.6 days longer in giant PTA patients compared to regular PTA patients.

Conclusion

Giant PTA compromised a significant percentage of all adenomas, which was higher than what is reported in the literature and might reflect a delay in diagnosis and lack of screening tests. Both giant and regular adenomas seem to run a similar clinical course, yet biochemical abnormalities in PTH levels may have a predictive value for adenoma weight.

•

Our sample included a high percentage of giant PTA compared to the literature. This might reflect a delay in diagnosis.

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Despite the difference in size, both giant and regular adenomas seem to run a similar clinical course, and the success of surgical treatment was found to be comparable.

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Biochemical abnormalities in PTH levels could have a potential role in predicting the weight and size of PTA.

Progressive rise in the prevalence of asymptomatic primary hyperparathyroidism in India: Data from PHPT registry

INTRODUCTION

Primary hyperparathyroidism (PHPT), a third common endocrine disorder, varies from asymptomatic disease, mostly seen in the West where routine biochemical screening is practiced, to the classical symptomatic disease mostly seen in the Eastern countries. We aimed to compare the demographic, clinical, biochemical measurements in patients with asymptomatic and symptomatic PHPT from the Indian PHPT registry.

MATERIAL AND METHODS

Data of PHPT patients from the last 25 years (1995-2019) were analyzed for demographic, clinical presentation and biochemical measurements, and compared these characteristics between asymptomatic and symptomatic PHPT patients.

RESULTS

Of the 554 patients, 54 (10%) patients had asymptomatic PHPT. There was a sharp rise in the proportion of asymptomatic PHPT patients of 3% in the first decade to 13% in the second decade of the century (p = 0.003). Patients with asymptomatic PHPT were significantly older (50 vs. 42 years; p < 0.0001) and had higher mean body mass index (27.8 vs. 23.5 kg/m²; p < 0.0001) compared to the symptomatic PHPT group. In addition, asymptomatic PHPT patients had significantly lower median plasma iPTH (180 vs. 370 pg/mL; p < 0.0001), serum alkaline phosphatase (119 vs. 172 IU/L; p < 0.0001), and parathyroid adenoma weight (1.0 vs. 2.62 g; p = 0.006) compared to the symptomatic PHPT group.

CONCLUSION

Although symptomatic PHPT is still most prevalent (> 90%) in India with higher indices of the disease and tumor weights, there is a progressive rise in the prevalence of asymptomatic PHPT patients in the last decade. Improvements in calcium and vitamin D nutrition might account for this change as in the Western series.

Symptomatic primary hyperparathyroidism in a young woman presenting with multiple skeletal destructions: a case report and review of literature

BACKGROUND

Multiple pathological manifestations are rarely present in patients with primary hyperparathyroidism (PHPT). Here we described a case of a young woman who presented with multiple skeletal destructions and received an unclear diagnosis at several hospitals.

CASE PRESENTATION

A 30-year-old woman was admitted to our hospital due to pain in both knees and walking difficulty that lasted for 6 and 2 years, respectively. Her laboratory test results revealed a high parathyroid hormone level (822 pg/ml) and hypercalcemia (2.52 mmol/L) in the blood. Parathyroid imaging revealed a lumpy concentration of radioactive uptake detected at the lower pole in the right lobe of the thyroid, and was nearly 2.2 cm * 2.4 cm in size. Next, the patient was treated with parathyroidectomy that resulted in a significant improvement in physiological and clinical symptoms. Moreover, the skeletal destruction and bone mineral density were significantly improved after a 5-years follow-up period.

CONCLUSIONS

Multiple skeletal destructions can be caused by PHPT that should be taken into consideration in young patients with complex bone lesions.

Primary Hyperparathyroidism in Sickle Cell Disease: An Unknown Complication of the Disease in Adulthood

Primary hyperparathyroidism (pHPT) is the third most common endocrine disorder and usually affects patients between 60 and 70 years of age. To our knowledge, this condition has never been studied in young patients with sickle cell disease (SCD). Our objective was to describe the clinical and biological characteristics of pHPT in adult patients with SCD and its management. We conducted a retrospective study that included SCD patients who were diagnosed with pHPT in four SCD referral centers. pHPT was defined by the presence of elevated serum calcium levels with inappropriate normal or increased parathyroid hormone (PTH) serum levels or histopathological evidence of parathyroid adenoma or hyperplasia. Patients with severe renal impairment (GFR <30 mL/min) were excluded. Twenty-eight patients (18 women, 64%; 22 homozygous genotype, 79%) were included. The median age at pHPT diagnosis was 41 years (interquartile range -IQR- 31.5-49.5). The median serum calcium and PTH concentration were, respectively, 2.62 mmol/L (IQR 2.60-2.78) and 105 pg/mL (IQR 69-137). Bone mineral density (BMD) revealed very low BMD (-2.5 SD) in 44% of patients explored (vs. 12.5% among 32 SCD patients matched for SCD genotype, sex, age, and BMI, p = 0.03). Fourteen patients (50%) received surgical treatment, which was successful in all cases, but four of these patients (29%) presented with pHPT recurrence after a median time of 6.5 years. Three of these patients underwent a second cervical surgery that confirmed the presence of a new parathyroid adenoma. These results suggest that SCD is a condition associated with pHPT in young subjects. SCD patients with pHPT have a high risk of very low BMD. A diagnosis of pHPT should be suspected in the presence of mild hypercalcemia or low BMD in SCD patients.

Primary Hyperparathyroidism in Sickle Cell Disease: An Unknown Complication of the Disease in Adulthood

Primary hyperparathyroidism (pHPT) is the third most common endocrine disorder and usually affects patients between 60 and 70 years of age. To our knowledge, this condition has never been studied in young patients with sickle cell disease (SCD). Our objective was to describe the clinical and biological characteristics of pHPT in adult patients with SCD and its management. We conducted a retrospective study that included SCD patients who were diagnosed with pHPT in four SCD referral centers. pHPT was defined by the presence of elevated serum calcium levels with inappropriate normal or increased parathyroid hormone (PTH) serum levels or histopathological evidence of parathyroid adenoma or hyperplasia. Patients with severe renal impairment (GFR <30 mL/min) were excluded. Twenty-eight patients (18 women, 64%; 22 homozygous genotype, 79%) were included. The median age at pHPT diagnosis was 41 years (interquartile range -IQR- 31.5-49.5). The median serum calcium and PTH concentration were, respectively, 2.62 mmol/L (IQR 2.60-2.78) and 105 pg/mL (IQR 69-137). Bone mineral density (BMD) revealed very low BMD (-2.5 SD) in 44% of patients explored (vs. 12.5% among 32 SCD patients matched for SCD genotype, sex, age, and BMI, p = 0.03). Fourteen patients (50%) received surgical treatment, which was successful in all cases, but four of these patients (29%) presented with pHPT recurrence after a median time of 6.5 years. Three of these patients underwent a second cervical surgery that confirmed the presence of a new parathyroid adenoma. These results suggest that SCD is a condition associated with pHPT in young subjects. SCD patients with pHPT have a high risk of very low BMD. A diagnosis of pHPT should be suspected in the presence of mild hypercalcemia or low BMD in SCD patients.

Serum Vitamin D Level Does not Affect The Sensitivity of Parathyroid Adenoma Localization Tests

The aim of the present study was to evaluate the predictive value of 25-hydroxyvitamin D, calcium and parathormone level, co-existence of thyroid nodule, thyroidectomy history and adenoma volume on the success of neck ultrasound (US) and technetium-99m sestamibi (MIBI) scan in primary hyperparathyroidism (PHP) patients. This study included 256 patients with PHP who underwent parathyroidectomy. 169 (%66) patients had vitamin D deficiency and 56 (%22) of patients had insufficiency. The sensitivity of US and MIBI studies showed no difference between vitamin D deficiency, insufficiency and replete groups (%80.5, %82 and %71 (p > 0.05) and %81, %84 and %71 respectively (p > 0.05)). Vitamin D level was not found to be an independent predictor of localization on either US or MIBI scan after adjusting for different variables (p > 0.05). Calcium level was found to be an independent predictor for US sensitivity (r²:0,033, p:0,032) and parathormone level for MIBI sensitivity (r²:0,05, p:0,025). The co-existence of nodular thyroid disease and history of thyroidectomy significantly decreased the sensitivity of US (%76 and %43). MIBI sensitivity was not impaired by nodular disease but the history of thyroidectomy also impaired the sensitivity of MIBI (%43). As a result vitamin D level does not affect the sensitivity of preoperative localization tests.

25-Hydroxyvitamin D and Vitamin D Binding Protein Levels in Patients With Primary Hyperparathyroidism Before and After Parathyroidectomy

Objective: To evaluate vitamin D binding protein and free 25-hydroxyvitamin D [25(OH)D] levels in healthy controls compared to primary hyperparathyroidism (PHPT) patients, and to examine PHPT before and after surgery. Methods: Seventy-five PHPT patients and 75 healthy age, gender, and body mass index (BMI) -matched control subjects were examined. In addition, 25 PHPT patients underwent parathyroidectomy and had a 3-month follow up visit. Levels of total and free 25(OH)D, DBP, and intact parathyroid hormone (iPTH) were determined before and 3 months after surgery. Results: There was no significant difference in age and BMI between PHPT patients and controls. Levels of 25(OH)D and DBP were lower in PHPT patients compared to controls (p < 0.01). There was no significant difference in calculated free and bioavailable 25(OH)D levels between PHPT patients and controls. Calcium and iPTH levels decreased to normal but DBP and DBP-bound-25(OH)D increased (P < 0.001) after parathyroidectomy. Levels of DBP were inversely correlated with iPTH (r = -0.406, P < 0.001) and calcium levels (r = -0.423, P < 0.001). Conclusion: Serum DBP levels were lower in patients with PHPT and parathyroidectomy restored DBP levels. We suggest that lower DBP levels is one of contributing mechanisms of low total 25(OH)D in PTHP patients and the total 25(OH)D levels might not reflect true vitamin D status in PHPT patients.

Pre-operative localization of abnormal parathyroid tissue by 99mTc-sestamibi in primary hyperparathyroidism using four-quadrant site analysis: an evaluation of the predictive value of vitamin D deficiency

CONTEXT

Accurate preoperative localization of abnormal parathyroid tissue aids importantly in minimally invasive parathyroidectomy in patients with primary hyperparathyroidism. Vitamin D deficiency may possibly influence the success and characteristics of pre-operative localization because it is associated with more active disease and possibly larger adenomas. This could increase the sensitivity of the sestamibi to identify abnormal parathyroid tissue, but earlier reports are conflicting. Vitamin D deficiency could also influence the nature of preoperative localization because it could lead to multi-gland stimulation of parathyroid tissue giving an appearance of multi-gland disease, which may lower accuracy of preoperative localization with sestamibi.

OBJECTIVE

To examine the relationship between vitamin D deficiency and correct parathyroid tissue localization by four-pole thyroid quadrant analysis.

DESIGN

Retrospective study.

SETTING

Referral center.

PARTICIPANTS

A total of 138 patients were divided into three groups according to the level of 25OHD; <20 ng/mL (vitamin D deficient), ≥20 to <30 ng/mL (vitamin D insufficient) and ≥30 ng/mL (vitamin D replete).

MAIN OUTCOMES

Quadrant localization using ^99mTc-sestamibi/SPECT.

RESULTS

Among those with single-gland disease, the proportion of patients with correct quadrant localization were 60.0, 68.3 and 63.5% (p = 0.778), and the accuracy of sestamibi was 89.3, 90.6 and 89.9% for the deficient, insufficiency and replete groups, respectively. Among those with multi-gland disease, the proportion of patients with correct quadrant localization were 50.0, 25.0 and 18.2% (p = 0.619) while the accuracy was 50.0, 50.0 and 45.5%, respectively. Multi-gland disease did not occur more frequently in any of the three groups (p = 0.296).

CONCLUSIONS

Vitamin D levels do not affect the accuracy of preoperative localization with sestamibi.

Primary hyperparathyroidism

In this Review, we describe the pathogenesis, diagnosis and management of primary hyperparathyroidism (PHPT), with a focus on recent advances in the field. PHPT is a common endocrine disorder that is characterized by hypercalcaemia and elevated or inappropriately normal serum levels of parathyroid hormone. Most often, the presentation of PHPT is asymptomatic in regions of the world where serum levels of calcium are routinely measured. In addition to mild hypercalcaemia, PHPT can manifest with osteoporosis and hypercalciuria as well as with vertebral fractures and nephrolithiasis, both of which can be asymptomatic. Other clinical forms of PHPT, such as classical disease and normocalcaemic PHPT, are less common. Parathyroidectomy, the only curative treatment for PHPT, is recommended in patients with symptoms and those with asymptomatic disease who are at risk of progression or have subclinical evidence of end-organ sequelae. Parathyroidectomy results in an increase in BMD and a reduction in nephrolithiasis. Various medical therapies can increase BMD or reduce serum levels of calcium, but no single drug can do both. More data are needed regarding the neuropsychological manifestations of PHPT and the pathogenetic mechanisms leading to sporadic PHPT, as well as on risk factors for complications of the disorder. Future work that advances our knowledge in these areas will improve the management of the disorder.

Comparison of Initial Clinical Presentations between Primary Hyperparathyroidism Patients from New Brunswick and Changsha

PURPOSE

To compare the initial clinical features, laboratory values, and bone mineral density among patients with primary hyperparathyroidism (PHPT) in Changsha (China) and New Brunswick (USA).

METHODS

In this retrospective study, we reviewed 169 PHPT patients who presented at Robert Wood Johnson University Hospital and 133 PHPT patients who presented at the Second Xiangya Hospital of Central South University in the same time period. The following characteristics were compared between the groups: age, gender, BMI, serum calcium, alkaline phosphatase (AKP), albumin, intact PTH (iPTH), 25-hydroxyvitamin D (25 (OH) D), fasting blood glucose levels, and bone mineral density (BMD). All these parameters were also compared according to gender and menopausal status. iPTH associations were also assessed along with several other parameters.

RESULTS

PHPT patients from Changsha had higher serum calcium, iPTH, and AKP levels but lower 25 (OH) D levels than the patients from New Brunswick (p < 0.05). Patients in Changsha had lower T-scores and Z-scores in both the lumbar spine and hip regions than those in New Brunswick (p < 0.05). Patients in New Brunswick had lower percentages of parathyroid adenoma and kidney stones. Serum iPTH level was positively correlated with serum calcium and serum AKP levels in both Changsha and New Brunswick (p < 0.05).

CONCLUSIONS

There are distinct biochemical and clinical differences between patients with PHPT in China and the United States. Our study revealed that Asian PHPT patients from Changsha presented more severe PHPT profiles, lower bone mineral density, and higher incidence of renal stones.

Selective Parathyroid Hormone Venous Sampling in Patients with Persistent or Recurrent Primary Hyperparathyroidism and Negative, Equivocal or Discordant Noninvasive Imaging

BACKGROUND

In patients with persistent (P-PHPT) or recurrent (R-PHPT) primary hyperparathyroidism, preoperative localization is important. Selective parathyroid hormone venous sampling (sPVS) is an invasive technique that can be used to regionalize and/or lateralize the source of PHPT when noninvasive imaging studies are nonlocalizing. The aim of the present study was to assess the role of sPVS in the preoperative evaluation of patients with P-PHPT or R-PHPT and negative, equivocal, or discordant noninvasive imaging localization.

METHODS

After IRB-approval a retrospective review of all patients with P-PHPT or R-PHPT and nonlocalizing noninvasive imaging that underwent sPVS from 2000 to 2014 was performed. The location of the source of PHPT at sPVS was predicted by a parathyroid hormone (PTH) gradient and compared to the surgical, pathology, and biochemical follow-up data as the gold standard. Sensitivity and positive predictive value (PPV) were calculated.

RESULTS

Of 30 patients who underwent sPVS, 12 patients did not undergo surgical exploration due to negative or non-localizing PTH gradient (n = 8) or opted for medical management (n = 4). Of the 18 patients who underwent surgical exploration, 17 (94 %) had a positive PTH gradient and pathologic parathyroid tissue identified at surgery. Sensitivity and PPV of sPVS were 93 and 77 %, respectively, for all surgical cases, 86 and 60.0 % for cervical cases (n = 11), and 100 and 100 % for mediastinal cases (n = 7). Sixteen patients (89 %) were surgically cured.

CONCLUSIONS

In patients with P-PHPT or R-PHPT and nonlocalizing imaging studies, sPVS is a sensitive test for localizing the source of PHPT when a positive PTH gradient is present.

Regional Clinical and Biochemical Differences among Patients with Primary Hyperparathyroidism

Background:

Environmental habitat may play a role in clinical disparities of primary hyperparathyroidism (pHPT) patients.

Aims:

To compare preoperative clinical symptoms and associated conditions and surgical findings in patients with pHPT, living in different geographical regions from the Black Sea, Mediterranean and Anatolia regions.

Study Design:

Retrospective, clinical-based multi-centric study of 694 patients with pHPT.

Methods:

Patients from 23 centers and 8 different geographical regions were included. Data related to baseline demographics, clinical, pathologic and treatment characteristics of 8 regions were collected and included age, gender, residential data, symptoms, history of fracture, existence of brown tumor, serum total Ca and p levels, serum parathormone (PTH) levels, serum 25-OH vitamin D levels, bone mineral density, size of the resected abnormal parathyroid gland(s), histology, as well as the presence of ectopia, presence of dual adenoma, and multiple endocrine neoplasia (MEN)- or familial-related disease.

Results:

The median age was 54. Asymptomatic patient rate was 25%. The median PTH level was 232 pg/mL and serum total Ca was 11.4 mg/dL. Eighty-seven percent of patients had an adenoma and 90% of these had a single adenoma. Hyperplasia was detected in 79 patients and cancer in 9 patients. The median adenoma size was 16 mm. Significant parameters differing between regions were preoperative symptoms, serum Ca and p levels, and adenoma size. All patients from South-East Anatolia were symptomatic, while the lowest p values were reported from East Anatolia and the largest adenoma size, as well as highest Ca levels, were from Bulgaria.

Conclusion:

Habitat conditions vary between geographical regions. This affects the clinicopathological features of patients with pHPT.

Impact of vitamin D deficiency on the clinical and biochemical phenotype in women with sporadic primary hyperparathyroidism

The purpose of the study was to evaluate the relationship between serum 25(OH)D and the clinical phenotype in 215 consecutive Italian Caucasian women with sporadic primary hyperparathyroidism (PHPT) not taking vitamin D supplements. The study was performed at a single Italian tertiary center. PHPT-related manifestations, serum 25(OH)D, and other parameters of calcium metabolism and bone mineral density (BMD) by DXA were recorded. Serum 25(OH)D was negatively correlated with age (r = -0.18; P = 0.006), BMI (r = -0.20; P = 0.002), PTH (r = -0.21; P = 0.001), bone-specific alkaline phosphatase (BSAP) (r = -0.27; P < 0.001), and eGFR (r = -0.22; P = 0.01), and positively with serum creatinine and 1/3 distal radius BMD (R-BMD; r = 0.17; P = 0.015). In a multivariate regression analysis, serum 25(OH)D remained significantly correlated with age (r = -0.18; P = 0.005), BMI (r = -0.23; P = 0.049), serum PTH (r = -0.01; P = 0.023), BSAP (r = -0.01; P = 0.023) and eGFR (r = -0.09; P = 0.001), but not with R-BMD. Serum 25(OHD) was higher in patients with nephrolithiasis than in those without nephrolithiasis (18.5 ± 8.8 vs. 15.6 ± 8.0 ng/ml; P = 0.029), whereas no difference was found between fractured and unfractured patients (16.8 ± 9.3 vs. 16.0 ± 7.7; P = 0.663). There was a statistically significant inverse correlation between vitamin D status [defined by quartiles of measured values as well as commonly accepted cutoffs of serum 25(OH)D] and severity of the disease, as reflected by higher PTH and BSAP, but not by meeting the latest guidelines for parathyroidectomy. In conclusion, a low vitamin D status is associated with some features reflecting a more severe biochemical and clinical phenotype of PHPT in Italian women not taking vitamin D supplements.

Effect of concomitant vitamin D deficiency or insufficiency on lumbar spine volumetric bone mineral density and trabecular bone score in primary hyperparathyroidism

Lower vitamin D and higher parathyroid hormone (PTH) levels are associated with higher volumetric BMD and bone strength at the lumbar spine as measured by central quantitative computed tomography in primary hyperparathyroidism (PHPT), but there are no differences in bone microarchitecture as measured by trabecular bone score (TBS).

INTRODUCTION

The purpose of this study was to evaluate the association between 25-hydroxyvitamin D (25OHD) and volumetric bone mineral density (vBMD) and the TBS at the lumbar spine (LS) in PHPT.

METHODS

This is a cross-sectional analysis of PHPT patients with and without low 25OHD. We measured vBMD with quantitative computed tomography (cQCT) and TBS by dual-energy X-ray absorptiometry (DXA) at the LS in 52 and 88 participants, respectively.

RESULTS

In the cQCT cohort, those with lower vitamin D (<20 vs. 20-29 vs. ≥30 ng/ml) tended to be younger (p = 0.05), were less likely to use vitamin D supplementation (p < 0.01), and had better renal function (p = 0.03). Those with 25OHD <20 ng/ml had 80 and 126 % higher serum PTH levels respectively vs. those with 25OHD 20-29 ng/ml (p = 0.002) and 25OHD ≥30 ng/ml (p < 0.0001). Covariate-adjusted integral and trabecular vBMD were higher in those with 25OHD 20-29 vs. those with 25OHD ≥30 ng/ml, but those with 25OHD <20 did not differ. Because there were few participants with 25OHD deficiency, we also compared those with vitamin D <30 vs. ≥30 ng/ml. Covariate-adjusted integral and trabecular vBMD were 23 and 30 % higher respectively (both p < 0.05) in those with vitamin D <30 vs. ≥30 ng/ml. TBS was in the partially degraded range but did not differ by vitamin D status.

CONCLUSION

In mild PHPT, lower 25OHD is associated with higher PTH, but vitamin D deficiency and insufficiency using current clinical thresholds did not adversely affect lumbar spine skeletal health in PHPT. Further work is needed to determine if higher vBMD in those with lower vitamin D is due to an anabolic effect of PTH.

Clinical and laboratory profile of primary hyperparathyroidism in Kashmir Valley: A single-center experience

BACKGROUND

Although primary hyperparathyroidism (PHPT) has become an asymptomatic disease in the West, in India, PHPT is still an uncommonly diagnosed, overtly symptomatic disease with skeletal, muscular, and renal manifestations.

AIMS

To describe the profile and surgical outcome of 78 consecutive PHPT patients over a period of two decades at a single center.

MATERIALS AND METHODS

All patients who underwent evaluation and surgery for PHPT from January 1996 to December 2015 were included. Evaluation included measurement of serum total calcium, inorganic phosphorus, alkaline phosphatase, intact parathyroid hormone, 25-hydroxy Vitamin D, 24 hour urinary calcium and radiological survey. Ultrasonography neck and technetium-99m sestamibi scan were used for preoperative localization.

RESULTS

A total of 78 patients were identified during the two decades of whom 29 patients were studied retrospectively and 49 patients prospectively. Mean age of patients was 44.72 ± 12.46, and male:female ratio was 1:6. The most common presenting features were nephrolithiasis and/or nephrocalcinosis (64.10%), bone pain (44.1%), abdominal pain (39%), constipation (26%), and myopathy (14.10%). Fractures were present only in 10.25%, and brown tumors in 6.41% patients. The cure rate in our series was 96.15%. The mean parathyroid gland weight was 2.05 ± 3.03 g. None of the 41 patients in whom long-term follow-up was available, had recurrence of PHPT.

CONCLUSIONS

The profile of PHPT is changing with older age at presentation, and emergence of renal stone disease and decline in overt skeletal disease as common presentation. The parathyroid weight in our study resembles that reported from developed countries.

Challenging neck mass: non-functional giant parathyroid adenoma

A 46-year-old man was referred to our ear, nose and throat department after the accidental discovery of a large retrotracheal mass. In order to obtain the diagnosis and to plan treatment he underwent a full battery of tests (CT, MRI, blood tests, hormonal assays, ultrasounds, thyroid scintigraphy, urine tests and fine-needle aspiration of the mass), but none of these was able to define the true nature of such cervical mass. Only after surgical excision and histological evaluation, it was diagnosed as an exceptional case of giant non-functional parathyroid adenoma.

Characteristics of patients operated for primary hyperparathyroidism at university hospitals in Türkiye: differences among Türkiye's geographical regions

Purpose

The aim of this study was to define the clinical and laboratory characteristics of patients operated on for primary hyperpatathyroidism (PHPT) at university hospitals in Türkiye, and to investigate the differences in the clinical presentations of the disease between different geographical regions.

Methods

Patients operated on for PHPT in the university hospitals of Türkiye were included in the study. The demographic, clinical, and laboratory findings and the operational data of the patients were investigated according to the whole country and to different geographical regions. Comparisons were performed according to whole country and regions.

Results

A total of 1,162 cases were included in the study from different regions and 20 university hospitals. The mean age of patients was 52.4 ± 0.38 (mean ± standard error) in the general population of Türkiye. The rates of hypertension, urolithiasis, bone disease and 25-hydroxyvitamin D insufficiency were 35%, 18.6%, 67.6%, and 63%, respectively. The median parathormone (PTH), serum total calcium (Ca⁺²) and phosphorus value were 220 pg/mL (range, 70–2,500 pg/mL), 11.2 mg/dL (range, 9.5–11.2 mg/dL), and 2.4 mg/dL (range, 1–4.7 mg/dL), respectively. The median size of the adenomas resected was 16 mm (range, 4–70 mm). Significant differences were observed in the clinical and laboratory findings of the patients operated on due to PHPT between different geographical regions of Türkiye (P < 0.05).

Conclusion

The clinical and laboratory characteristics of the patients with PHPT in different geographical regions of Türkiye differ. Furthermore, the general findings of the cases in Türkiye give us a hint that the severity of the disease here is somewhere between Eastern and Western countries.

Novel multiple endocrine neoplasia type 1 variations in patients with sporadic primary hyperparathyroidism

BACKGROUND AND OBJECTIVES

Primary hyperparathyroidism (PHPT) can occur either as a sporadic case or in association with syndromes such as multiple endocrine neoplasia. Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal-dominant disease resulting from mutations in MEN1 gene encoding a 621 amino acid long tumor suppressor protein "menin." We report here the results of MEN1 screening in 31 patients diagnosed with sporadic PHPT.

MATERIALS AND METHODS

Diagnosis of sporadic PHPT was made when blood urea and serum creatinine were normal, serum parathyroid hormone was high, and parathyroid enlargement could be localized on ultrasound and/or parathyroid scan. A total of 31 patients and 50 healthy volunteers were recruited for molecular analysis after taking informed consent.

RESULTS

Major symptoms at presentation were bone pain, fatigue, muscle weakness, and renal stones. Molecular genetic analysis revealed the presence of two novel intronic variations, c. 913-79T>A and c. 784-129T>A which by human splicing finder are predicted to cause potential alteration of splicing by either activating an intronic cryptic acceptor site or converting a conserved exonic splicing silencer sequence to an exonic splicing enhancer site. Apart from these, two reported polymorphisms rs144677807 and rs669976 were seen only in patients and none of the controls. Other reported polymorphisms rs2071313 and rs654440 were identified both in controls and patients.

CONCLUSIONS

This is the first study of MEN1 gene screening in sporadic PHPT in India reporting on the clinical and genetic findings, wherein two novel intronic variations c. 913-79T>A and c. 784-129T>A were identified showing their possible role in disease causation.

Diffuse parathyroid hormone expression in parathyroid tumors argues against important functional tumor subclones

OBJECTIVE

Primary hyperparathyroidism is usually characterized by a monoclonal parathyroid tumor secreting excess parathyroid hormone (PTH). The main regulator of PTH secretion is calcium and the calcium-PTH set point is shifted in parathyroid tumor cells. We sought to investigate the relationship between tumor PTH and PTH mRNA expression and clinical presentation as well as the regulatory factors including phosphate, vitamin D, and fibroblast growth factor 23.

DESIGN

A total of 154 parathyroid tumors were analyzed by PTH immunohistochemistry and chromogenic in situ hybridization of PTH mRNA. A subset of samples (n = 34) was analyzed using quantitative real-time PCR.

RESULTS

Low tumor PTH mRNA level was significantly associated with low tumor PTH immunoreactivity (P = 0.026), but the two did not correlate with regard to histological distribution within individual tumors. Tumors displaying reduced PTH mRNA levels as compared with normal rim were significantly larger (P = 0.013) and showed higher expression of the calcium-sensing receptor (CASR) (P = 0.046). Weaker tumor PTH mRNA level was significantly associated with higher concentration of circulating 25-hydroxyvitamin D (P = 0.005). No significant correlation was seen between PTH immunoreactivity and patient biochemistry. Tumor weight was strongly associated with circulatory concentrations of calcium and PTH.

CONCLUSIONS

No areas with apparently higher PTH expression were identified, perhaps suggesting that hyper functioning parathyroid tumor subclones should be rare. Circulating 25-hydroxyvitamin D levels may influence tumor PTH expression in vivo. If PTH immunoreactivity reflects the tumor calcium-PTH set point, our data imply that the main determinant of disease severity should be tumor weight.

Low vitamin D levels have become less common in primary hyperparathyroidism

We compared temporal trends in serum 25-hydroxyvitamin D and parathyroid hormone (PTH) in two primary hyperparathyroidism (PHPT) cohorts recruited 20 years apart. The prevalence of 25-hydroxyvitamin D levels <20 and <30 ng/mL declined by 30-50 %, respectively, and was accompanied by lower PTH. In the older cohort, higher PTH may be due to lower 25-hydroxyvitamin D.

INTRODUCTION

Vitamin D deficiency may exacerbate PHPT. Whether there have been temporal trends in 25-hydroxyvitamin D (25OHD) levels in PHPT is unclear. The prevalence of low vitamin D levels (25OHD <20 and <30 ng/mL) and associated biochemical and bone mineral density (BMD) profiles were assessed in two PHPT cohorts recruited over 20 years apart.

METHODS

This is a cross-sectional comparison of serum 25OHD levels, calciotropic hormones, and BMD between two PHPT cohorts recruited at the same hospital: the "old" (N = 103) and "new" (N = 100) cohorts were enrolled between 1984 and 1991 and between 2010 and 2014, respectively.

RESULTS

Mean 25OHD levels were 26 % higher in the new cohort (23 ± 10 vs. 29 ± 10 ng/mL, p < 0.0001). Levels of 25OHD <20 and <30 ng/mL declined from 46 and 82 %, respectively, to 19 and 54 % (both p < 0.0001). Supplemental vitamin D use was common in the new (64 %) but not the old cohort (0 %). The new cohort demonstrated 33 % lower serum PTH levels (p < 0.0001). Neither serum nor urine calcium differed. BMD was higher in the new cohort at all skeletal sites (all p < 0.001).

CONCLUSION

With the rise in vitamin D supplementation over the last two decades, low 25OHD levels are no longer common in PHPT patients in the New York area. Those with 25OHD <20 and <30 ng/mL have declined by over 50 and 30 %, respectively. The lower mean PTH levels in the new cohort are most likely accounted for by higher vitamin D intake. Whether improved vitamin D status also underlies the relatively higher BMD in the more vitamin D replete cohort of PHPT patients is unknown.

Vitamin D in Primary Hyperparathyroidism: Effects on Clinical, Biochemical, and Densitometric Presentation

CONTEXT

Vitamin D (25-hydroxyvitamin D [25OHD]) deficiency (<20 ng/mL) and insufficiency (20-29 ng/mL) are common in primary hyperparathyroidism (PHPT), but data regarding their skeletal effects in PHPT are limited.

OBJECTIVE

The objective was to evaluate the association between 25OHD levels and PHPT severity.

DESIGN, SETTINGS, AND PARTICIPANTS

This is a cross-sectional analysis of 100 PHPT patients with and without 25OHD insufficiency and deficiency from a university hospital setting.

OUTCOME MEASURES

We measured calciotropic hormones, bone turnover markers, and bone mineral density (BMD) by dual x-ray absorptiometry.

RESULTS

Lower 25OHD was associated with some (PTH: r = -0.42; P < .0001; 1,25-dihydroxyvitamin D: r = -0.27; P = .008; serum PO4: r = 0.31; P = .002) but not all (serum/urine calcium) indicators of PHPT severity. Lower 25OHD was also associated with younger age, higher body mass index, male gender, better renal function, and lower vitamin D intake. Comparison of those with deficient (<20 ng/mL; 19%) vs insufficient (20-29 ng/mL; 35%) vs replete (≥30 ng/mL; 46%) 25OHD demonstrated more severe PHPT as reflected by higher PTH (mean ± SEM, 126 ± 10 vs 81 ± 7 vs 72 ± 7 pg/mL; P < .0001) but no difference in nephrolithiasis, osteoporosis, fractures, serum or urinary calcium, bone turnover markers, or BMD after adjustment for age and weight. In women, T-scores at the 1/3 radius were lower in those with 25OHD of 20-29 ng/mL, compared to those who were vitamin D replete (P = .048). In multiple regression modeling, 25OHD (but not PTH) was an independent predictor of 1/3 radius BMD.

CONCLUSION

Vitamin D deficiency is associated with more severe PHPT as reflected by PTH levels, but effects on BMD are limited to the cortical 1/3 radius and are quite modest. These data support international guidelines that consider PHPT patients with 25OHD <20 ng/mL to be deficient. However, in this cohort with few profoundly vitamin D-deficient patients, vitamin D status did not appear to significantly impact clinical presentation or bone density.

Hypertension, Antihypertensive Medications, and Risk of Incident Primary Hyperparathyroidism

CONTEXT

Hypertension is associated with higher PTH levels, and specific antihypertensive medications may modulate PTH. Whether hypertension or the use of specific antihypertensive medications influences the risk of developing incident primary hyperparathyroidism (P-HPTH) is not known.

OBJECTIVE

The purpose of this study was to investigate whether a history of hypertension and the use of specific antihypertensive medications determine the risk for developing P-HPTH in a large prospective study.

DESIGN/PARTICIPANTS

A longitudinal prospective cohort of female nurses in the Nurses' Health Study I (n = 75 600), who did not have P-HPTH at baseline and completed a questionnaire assessment of lifetime history of P-HPTH were followed from 1986 to 2008. Most participants were white and postmenopausal.

SETTING

The study was a nationwide cohort study.

MAIN OUTCOME MEASURE

Incident P-HPTH was assessed initially via questionnaire and then was confirmed by medical record review. Cox proportional hazards models were used to adjust for potential confounders.

RESULTS

We documented 347 incident cases of P-HPTH during 1 719 416 person-years of follow-up. The age-adjusted relative risk (RR) for incident P-HPTH associated with hypertension was 1.80 (95% confidence interval [CI], 1.43-2.26), and the multivariate-adjusted RR was 1.45 (95% CI, 1.10-1.91). Among participants with a history of hypertension, the use of furosemide, when compared with the use of other antihypertensive medications, was associated with increased risk for developing P-HPTH; age-adjusted RR for incident P-HPTH was 1.79 (95% CI, 1.15-2.79) and multivariate-adjusted RR was 1.71 (95% CI, 1.08-2.71).

CONCLUSIONS

In a large longitudinal prospective cohort study of mostly older white women, a history of hypertension and use of furosemide were associated with a significantly higher risk of developing P-HPTH.

Secular trends in the incidence of primary hyperparathyroidism over five decades (1965-2010)

Introduction of automated serum calcium measurements in the 1970s resulted in a sharp rise in primary hyperparathyroidism (PHPT) incidence. However, recent investigations suggest a significant rise in PHPT incidence for unclear reasons. Our objective was to update our population-based secular trends in PHPT incidence, to determine if there has been a significant rise in PHPT incidence as suggested by others, and, if possible, to identify changes in clinical practice that might be responsible. Rochester, Minnesota, residents who met the criteria for PHPT from 2002 through 2010 were identified through the medical records-linkage system of the Rochester Epidemiology Project and added to the historical cohort beginning in 1965. Incidence rates were adjusted to the 2010 US white population. Altogether, 1142 Rochester residents have been diagnosed with PHPT since 1965, including 341 in 2002-2010. Over time, two periods of increased PHPT incidence occurred, one beginning in 1974 (121.7 per 100,000 person-years) and a second peak (86.2 per 100,000 person-years) starting in 1998. The median age of PHPT subjects has increased significantly from 55 years in 1985-1997 to 60 years of age in 1998-2010 and more patients (36%) had a parathyroidectomy in 1998-2010. Although serum calcium measurement has declined since 1996, there was a progressive increase in parathyroid hormone testing between 1994 and 2008. There was also a rise in orders for bone mineral density measurements in women since 1998, which peaked in 2003-2004. A second sharp rise in PHPT incidence occurred in our community in 1998, simultaneously with the introduction of national osteoporosis screening guidelines, Medicare coverage for bone density measurement, and new medications for the treatment of osteoporosis. Case ascertainment bias from targeted PHPT screening in patients being evaluated for osteoporosis is the most likely explanation.

Parathyroid adenoma in a patient with familial hypocalciuric hypercalcaemia

A 57-year-old man with symptoms of fatigue, joint pains and insomnia was found to have hypercalcaemia secondary to hyperparathyroidism with a corrected calcium of 2.61 mmol/L (2.2-2.6 mmol/L) and a serum parathyroid hormone (PTH) of 86 pg/mL (10-65 pg/mL). Preoperative workup demonstrated a parathyroid adenoma in the right upper position and he proceeded to surgery. Postoperatively, however, his symptoms remained unchanged and the corrected calcium remained elevated at 2.87 mmol/L with a PTH of 59 pg/mL. He had no family history of hypercalcaemia. Further investigations revealed low 24 h urinary calcium level and a low urine calcium to creatinine ratio. Genetic testing revealed a mutation in exon 4 of the calcium sensing receptor (CaSR) confirming a diagnosis of familial hypocalciuric hyercalcaemia (FHH). The case is an example of a rare phenomenon when a parathyroid adenoma develops in patients with FHH.

Primary hyperparathyroidism from a probable ectopic parathyroid adenoma with severe skeletal disease and vitamin D deficiency

Primary hyperparathyroidism (PHPT) may lead to skeletal deformities, fractures and renal failure in symptomatic patients if untreated. We present a case of a 30-year-old woman presented with muscle weakness, weight loss, hypercalcaemia and a pathological fracture, eventually with rapidly progressive musculoskeletal disease. Subsequent biochemical, radiographic and scintigraphy findings were consistent with PHPT from an ectopic mediastinal adenoma, and concomitant vitamin D deficiency. The severe hypercalcaemia was adequately temporised with hydration, forced diuresis and intravenous bisphosphonates. Removal of the adenoma by video-assisted thoracoscopic surgery was contemplated; however, consent was withdrawn precluding histological confirmation. A review of literature shows the changing profiles of patients with PHPT, the uncommon occurrence of parathyroid adenomas in ectopic locations and possible association between severity of PHPT and vitamin D status.

Do giant parathyroid adenomas represent a distinct clinical entity?

BACKGROUND

The size of abnormal parathyroid glands in patients with primary hyperparathyroidism (PHPT) is highly variable, but the clinical significance of giant glands is unknown.

METHODS

We reviewed 300 consecutive patients after parathyroidectomy for PHPT. We compared patients with giant parathyroid adenomas (weight ≥95th percentile) with the remaining patients.

RESULTS

Giant adenomas were defined as weight ≥95th percentile or 3.5 g (median, 0.61; range, 0.05-29.93). Patients with giant adenomas had a greater mean preoperative calcium level, greater mean parathyroid hormone (PTH) level, and were less likely to have multiglandular or symptomatic disease. Giant adenomas were successfully localized on imaging in 87% of patients, which was not increased over other patients (82%). There were no differences between the groups in age, gender, gland location, or the incidence of persistent or recurrent hyperparathyroidism. Finally, giant glands had an increased incidence of symptomatic postoperative hypocalcemia, including 1 patient who required rehospitalization after removal of a giant gland.

CONCLUSION

Giant parathyroid adenomas have a distinct presentation characterized by single gland disease and lower incidence of symptoms despite increased levels of calcium and PTH. Additionally, after resection of a giant adenoma, patients are more likely to develop symptomatic hypocalcemia.

Primary Hyperparathyroidism: A Tale of Two Cities Revisited - New York and Shanghai

In the 1970s, with the advent of biochemical multichannel screening in the United States and other western countries, the clinical presentation of primary hyperparathyroidism (PHPT) changed from a symptomatic to an asymptomatic disorder. However, in Asian countries, like China, PHPT did not show this evolution, but rather continued to be a symptomatic disease with target organ involvement. In this paper, we revisit the clinical features of PHPT in New York and Shanghai, representative United States and Chinese cites, over the past decade. The questions we address are whether the disease evolved in China to a more asymptomatic one and, whether in the United States further changes are evident. The results indicate that while PHPT continues to present primarily as an asymptomatic disease in the United States, a new phenotype characterized by normal serum calcium and high parathyroid hormone levels, normocalcemic PHPT, has emerged. Data from Shanghai demonstrates a trend for PHPT to present more commonly as an asymptomatic disorder in China. However, most patients with PHPT in China still manifest classical symptoms, i.e. nephrolithiasis and fractures. A comparison of the two cohorts shows that Chinese patients with PHPT are younger, with higher serum calcium and PTH levels, and lower 25-hydroxyvitamin D levels than patients in New York. Normocalcemic PHPT has not yet been recognized in Shanghai. In summary, although the phenotypes of PHPT in both cities are evolving towards less evident disease, sharp clinical and biochemical differences are still apparent in PHPT as expressed in China and the United States.

Vitamin d status in patients operated for primary hyperparathyroidism: comparison of patients from southern and northern europe

Aim. The interaction between vitamin D deficiency and primary hyperparathyroidism (PHPT) is not fully understood. The aim of this study was to investigate whether patients with PHPT from Spain and Sweden differed in vitamin D status and PHPT disease activity before and after surgery. Methods. We compared two cohorts of postmenopausal women from Spain (n = 126) and Sweden (n = 128) that had first-time surgery for sporadic, uniglandular PHPT. Biochemical variables reflecting bone metabolism and disease activity, including levels of 25-hydroxy vitamin D3 (25(OH)D) and bone mineral density, BMD, were measured pre- and one year postoperatively. Results. Median preoperative 25(OH)D levels were lower, and adenoma weight, PTH, and urinary calcium levels were higher in the Spanish cohort. The Spanish patients had higher preoperative levels of PTH (13.5 versus 11.0 pmol/L, P < 0.001), urinary calcium (7.3 versus 4.1 mmol/L, P < 0.001), and heavier adenomas (620 versus 500 g, P < 0.001). The mean increase in BMD was higher in patients from Spain and in patients with vitamin D deficiency one year after surgery. Conclusion. Postmenopasual women with PHPT from Spain had a more advanced disease and lower vitamin 25(OH)D levels. Improvement in bone density one year after surgery was higher in patients with preoperative vitamin D deficiency.

Bone disease in primary hyperparathyrodism

Nowadays, primary hyperparathyroidism (PHPT) is mostly a mild disease. Overt skeletal manifestations are rare but decreased bone mineral density (BMD) can still be demonstrated. Even in mild cases, excess parathyroid hormone (PTH) increases bone turnover leading to bone loss particularly at cortical sites. Conversely, a relative preservation of cancellous bone has been shown by histomorphometric analyses and advanced imaging techniques. An increased fracture rate has been demonstrated in untreated patients with PHPT at peripheral sites and in the spine. Parathyroidectomy (PTx) is the definitive cure for PHPT. With the restoration of normal PTH, bone resorption is quickly tapered down, while bone formation proceeds at the level of bone multicellular units, which were activated prior to PTx. The rapid refilling of the enlarged remodeling space and the subsequent matrix mineralization will result in an increase in BMD at sites rich in trabecular bone, such as lumbar spine and hip, which mainly occurs during the first 6-12 months after PTx. Cortical bone is less responsive to PTX because of the low rate of bone turnover, but sensible increases in BMD at the distal third of the radius can be observed in the long term. PTx seems to decrease the risk of fractures but more data are needed before a definitive conclusion on this important matter can be reached. Treatment with bisphosphonates can be considered for patients with low BMD who do not undergo PTx. Two-year treatment with alendronate has been shown to decrease bone turnover markers and increase BMD at the lumbar spine and hip, but not at the distal radius. Cinacalcet stably decreased serum calcium levels across a broad range of PHPT severity, but no change in BMD occurred in patients treated for up to 5.5 years.

Prolonged treatment with vitamin D in postmenopausal women with primary hyperparathyroidism

INTRODUCTION/BACKGROUND

Vitamin D deficiency further increases circulating parathyroid hormone (PTH) levels in patients with primary hyperparathyroidism (pHPT), with potential detrimental effects on bone mass.

METHODS

This was an observational clinical study in consecutive conservatively treated postmenopausal women (n=40) with pHPT and coexistent 25-hydroxyvitamin D deficiency (25OHD ≤50 nmol/l (≤20 ng/ml)). Patients who showed an increase in serum 25OHD above the threshold of vitamin D deficiency (>50 nmol/l; n=28) using treatment with various commonly prescribed vitamin D preparations were, for the purposes of statistical analyses, allocated to the treatment group. Patients who were retrospectively identified as having received no treatment with vitamin D and/or remained vitamin D deficient were considered as non-responders/controls (n=12). Adjusted calcium (adjCa), PTH and 25OHD concentrations were monitored in all subjects up to 54 months (mean observation period of 18±2 months).

RESULTS

Prolonged increased vitamin D intake, regardless of the source (serum 25OHD, increase from 32.2±1.7 nmol/l at baseline to 136.4±11.6 nmol/l, P<0.0001), significantly reduced serum PTH (13.3±1.1 vs 10.5±1.0 pmol/l, P=0.0001), with no adverse effects on adjCa levels (2.60±0.03 vs 2.60±0.02 mmol/l, P=0.77) and renal function tests (P>0.73). In contrast, serum PTH remained unchanged (15.8±2.6 vs 16.3±1.9 pmol/l, P=0.64) in patients who remained vitamin D deficient, with a significant difference between groups in changes of PTH (P=0.0003). Intrapartial correlation analyses showed an independent negative correlation of changes in 25OHD with PTH levels (r ic=-0.41, P=0.014).

CONCLUSIONS

Prolonged treatment with vitamin D in various commonly prescribed preparations appeared to be safe and significantly reduced PTH levels by 21%.

A mathematical model of calcium and phosphorus metabolism in two forms of hyperparathyroidism

Parathyroid hormone (PTH) plays a critical role in calcium and phosphorus metabolism. Interestingly, in two forms of hyperparathyroidism (excessive amount of PTH in the serum), the metabolic disturbances in patients with chronic kidney disease (CKD) significantly differ from those with primary hyperparathyroidism (PHP). Since an intuitive understanding of these PTH-linked regulatory mechanisms are hardly possible, we developed a mathematical model using clinical data (1586 CKD and 40 PHP patients). The model was composed of a set of ordinary differential equations, in which the regulatory mechanism of PTH together with other key factors such as 1,25-Dihydroxyvitamin D (1,25(OH)₂D) and calcium was described in the tissues including bone, the kidney, the serum, and the parathyroid glands. In this model, an increase in PTH was induced by its autonomous production in PHP, while PTH in CKD was elevated by a decrease in feedback inhibition of 1,25(OH)₂D in the serum, as well as an increase in stimulation by phosphorus in the serum. The model-based analysis revealed characteristic differences in the outcomes of hyperparathyroidism in CKD and PHP. The calcium exchange in bone, for instance, was predicted significantly higher in PHP than CKD. Furthermore, we evaluated the observed and predicted responses to the administration of calcimimetics, a recently developed synthetic drug that modulated efficacy of calcium-sensing receptors. The results herein support the notion that the described model would enable us to pose testable hypotheses about the actions of PTH, providing a quantitative analytical tool for evaluating treatment strategies of PHP and CKD.

The impact of vitamin D status and tumor size on the intraoperative parathyroid hormone dynamics in patients with symptomatic primary hyperparathyroidism

PURPOSE

The intraoperative parathyroid hormone (IOPTH) monitoring is a useful adjunct for predicting whether a cure has been obtained during parathyroidectomy. We studied the influence of vitamin D status and parathyroid tumor weight on the IOPTH dynamics for predicting a cure in patients with symptomatic primary hyperparathyroidism.

METHODS

Fifty-nine primary hyperparathyroidism patients with a single adenoma underwent curative surgery. Patients were grouped according to their serum 25-hydroxy vitamin D levels (deficient, insufficient and sufficient) and tumor weights (small, large and giant). The IOPTH results in patient groups were compared, and the percentage of the IOPTH decrease was examined for a correlation with the serum 25-hydroxy vitamin D level and tumor weight.

RESULTS

The sensitivity, specificity and overall accuracy of IOPTH in predicting a cure of hyperparathyroidism were 94.8, 100 and 93.2%, respectively. The percentage decrease in the IOTPH was significantly higher in the vitamin D deficient, compared to the vitamin D sufficient patients (p = 0.012); and in the patients with larger tumors, compared to those with smaller parathyroid tumors (p = 0.02). A statistically significant correlation was found between the percentage decrease in the IOPTH at 10 min post-tumor excision and the serum 25-hydroxy vitamin D level (p = 0.037), but not with the tumor weight (p = 0.208).

CONCLUSIONS

The IOPTH can accurately predict a cure in patients with severe primary hyperparathyroidism. The percentage of decrease in the IOPTH is steeper in patients with lower serum 25-hydroxy vitamin D levels and larger parathyroid tumors.

Vitamin D deficiency influences histomorphometric features of bone in primary hyperparathyroidism

INTRODUCTION

Vitamin D deficiency is common in patients with primary hyperparathyroidism (PHPT). The presence of low levels of vitamin D may affect the skeletal consequences of PHPT.

METHODS

In this cross-sectional study, transiliac crest bone biopsies were performed after double tetracycline labeling in patients with mild PHPT and analyzed according to serum levels of 25 hydroxyvitamin D (25OHD).

RESULTS

We studied 30 patients with mild PHPT (age 53 ± 11 years; 67% women; calcium 11.1 ± 1.0 mg/dl; PTH 149 ± 129 pg/ml). Serum 25OHD levels were low in the majority of subjects (mean 21 ± 11 ng/ml) and inversely associated with PTH (r = -0.69; p < 0.01). 25OHD levels were directly associated with cortical width (Ct.Wi; r = 0.46, p < 0.03) and trabecular separation (Tb.Sp; r = 0.41; p < 0.04), but inversely associated with cancellous bone volume (BV/TV; r = -0.39, p < 0.04). Subjects with 25OHD levels < 20 ng/ml (n = 14) and ≥ 20 ng/ml (n = 16) were compared. Groups did not differ by age, sex, menopausal status, serum calcium, creatinine, or 1,25(OH)₂D. PTH was 1.8-fold higher in subjects with 25OHD < 20 (265 ± 166 pg/ml vs. 95 ± 50 pg/ml; p < 0.01). On histomorphometric analysis, those with low 25OHD had lower Ct.Wi (541 ± 167 μm vs. 712 ± 200 μm; p < 0.03). Conversely, measures of trabecular microarchitecture were better in those with lower 25OHD, with higher BV/TV (26.1 ± 6.1% vs. 20.4 ± 6.4%; p < 0.03), greater trabecular number (Tb.N: 2.0 ± 0.4 mm⁻¹ vs. 1.8 ± 0.4 mm⁻¹; p < 0.04) and lower Tb.Sp (371 ± 90 μm vs. 472 ± 137 μm; p < 0.04). There were no differences between the groups in bone remodeling indices.

CONCLUSIONS

Low levels of 25OHD in patients with PHPT are associated with higher concentrations of PTH, greater catabolic effects in cortical bone and greater anabolic effects in trabecular bone.

Severe obesity is associated with symptomatic presentation, higher parathyroid hormone levels, and increased gland weight in primary hyperparathyroidism

CONTEXT

A relationship between primary hyperparathyroidism (PHPT) and obesity has been observed but is incompletely understood. Furthermore, obesity has been associated with vitamin D deficiency, suggesting that the three conditions may be linked.

OBJECTIVE

We hypothesized that PHPT in morbidly obese patients is more severe and that the difference may be explained by vitamin D deficiency. DESIGN AND SETTING, PARTICIPANTS, AND OUTCOME MEASURES: Records of 196 patients with surgically treated PHPT and known body mass index (BMI) were examined. Patients were stratified into three BMI groups: group I (nonobese), BMI < 25 kg/m(2) (n = 54); group II (non-severely obese), BMI 25-34 kg/m(2) (n = 102); and group III (severely obese), BMI 35 kg/m(2) or greater (n = 40).

RESULTS

Preoperative PTH levels were higher in group ΙΙΙ compared with group Ι (181 ± 153 vs. 140 ± 80 pg/ml, p = 0.04). Group III patients had larger tumors on average compared with group I (1.8 ± 1.5 vs. 1.04 ± 1.5 g, P = 0.0002). In group III, BMI positively correlated with parathyroid tumor weight (r = 0.5, P = 0.002). Postoperative PTH was higher in group III compared with group Ι (61 ± 41 vs. 44 ± 28 pg/ml, P = 0.02). There was higher frequency of depression, musculoskeletal symptoms, weakness, and gastroesophageal reflux disease in group III patients.

CONCLUSIONS

BMI positively correlated with parathyroid tumor weight independent of vitamin D. Severely obese patients have larger parathyroid tumor weight, higher pre- and postoperative PTH, and greater symptoms.

Cardiac structure and diastolic function in mild primary hyperparathyroidism

CONTEXT

Data on the presence, extent, and reversibility of cardiovascular disease in primary hyperparathyroidism (PHPT) are conflicting.

OBJECTIVE

To evaluate the heart in PHPT, we assessed cardiac structure and diastolic function in patients with mild PHPT compared with age- and sex-matched controls.

DESIGN

This was a case-control study.

SETTINGS

The study was conducted in a university hospital Metabolic Bone Diseases Unit.

PARTICIPANTS

Fifty-four men and women with PHPT and 76 controls without PHPT participated in the study.

OUTCOME MEASURES

We measured left ventricular mass index (LVMI), the presence of mitral annular calcification, the ratio of early to late diastolic mitral inflow velocities (E/A), and early diastolic velocity of the lateral mitral annulus using Doppler tissue imaging (tissue Doppler e').

RESULTS

Patients had mild disease with mean (+/-sd) serum calcium 10.5 +/- 0.5 mg/dl and PTH 96 +/- 45 pg/ml. LVMI and diastolic function were normal in PHPT. There was no difference in LVMI (98 +/- 23 vs. 96 +/- 24 g/m(2), P = 0.69) or the frequency of mitral annular calcification between PHPT cases and controls. Diastolic function variables (E/A and tissue Doppler e') were higher (better) in cases compared with controls, although both were within the reference range. PHPT patients with low E/A had higher serum PTH (121 +/- 36 vs. 89 +/- 46 pg/ml, P = 0.03) and calcium (10.8 +/- 0.4 vs. 10.5 +/- 0.5 mg/dl, P = 0.05) than those with normal values. Finally, we found LVMI to be inversely associated with serum 25-hydroxyvitamin D in PHPT (r = -0.29, P < 0.05). All findings persisted after adjustment for group differences in cardiovascular risk factors.

CONCLUSIONS

Patients with biochemically mild PHPT do not have evidence of increased left ventricular mass, diastolic dysfunction, or increased valvular calcifications. However, the data support an association between low vitamin D levels and the development of left ventricular hypertrophy in this disorder. Finally, the increased serum calcium and PTH levels in those with diastolic dysfunction suggest that disease severity may determine the presence of cardiac manifestations in PHPT.

Prevalence of vitamin D depletion among subjects seeking advice on osteoporosis: a five-year cross-sectional study with public health implications

We assessed vitamin D nutritional status in unselected consecutive patients seeking advice on osteoporosis. The prevalence of vitamin D depletion ranged from 15-72% depending upon the cut-off levels used for serum 25-hydroxyvitamin D, and the prevalence did not change over the 5 years of the study.

INTRODUCTION

Vitamin D depletion is a significant public health problem and has been studied in different populations using different cut-off levels, but the optimal level is yet to be established.

METHODS

In a cross-sectional study of 2,924 patients seen for osteoporosis advice we determined the prevalence of vitamin D depletion, as assessed by 25-hydroxyvitamin D (25-OHD), using three different cut-off levels stratified by gender, race and the year of the study over 5 years.

RESULTS

Mean age was 68.3 +/- 10.0 years; 90% women and 88% white. Mean 25-OHD level was 24.6 +/- 10 ng/ml and mean PTH was 48.4 +/- 32 pg/ml. The prevalence of vitamin D depletion was 15% with a cut-off level of <15 ng/ml, and rose to 32% and 72% with cut-off levels <20 ng/ml and <30 ng/ml, respectively. The prevalence was higher in men and blacks and remained constant over 5 years, regardless of the cut-off level. The expected inverse relationship between 25-OHD and PTH was observed irrespective of gender or ethnicity.

CONCLUSIONS

The prevalence of vitamin D depletion in patients seeking advice for osteoporosis is high and did not change over the 5 years of the study.

A very high incidence of low 25 hydroxy-vitamin D serum concentration in a French population of patients with primary hyperparathyroidism

Since the demonstration that vitamin D status might influence the clinical and biological expression of primary hyperparathyroidism (PHPT), a serum 25-hydroxy vitamin D (25-OHD) concentration of 50 nmol/l has been considered by an expert panel as the minimum level to be maintained in asymptomatic PHPT patients. Two yr after this recommendation, we aimed to evaluate the frequency of serum 25-OHD concentrations below this threshold in PHPT patients. In the present study, serum 25-OHD, second- and third-generation PTH, calcium, phosphate, magnesium, albumin and creatinine were measured in 72 out 145 consecutive PHPT patients operated on in our Endocrine Surgery Department, in whom blood samples were available before as well as two days after surgical intervention. Before surgery, the frequency of serum 25-OHD levels <50 nmol/l ranged from 91.5 to 100% whatever the classification used to identify patients: whole group, symptomatic vs asymptomatic, patients with calcium levels >3 vs <3 mmol/l. 25-OHD concentrations correlated negatively with the weight of adenoma, PTH levels, and total calcium concentrations measured before surgery. Pre-operative PTH levels, whatever the assay used, and total calcium concentrations were positively and significantly correlated. Two days post-surgery, 13 patients were moderately hypocalcemic. Neither pre-surgery 25-OHD nor PTH, calcium or phosphorus level or adenoma weight were predictive of post-operative hypocalcemia. The dramatic frequency of low 25-OHD concentrations in our PHPT patients demonstrates that the above-mentioned recommendation is far from being applied in France despite evidence of worsening expression of PHPT with decreasing 25-OHD serum levels.