Hiperparatiroidismo primario

Do large parathyroid adenomas increase the risk of severe hypercalcemia?

<b><br>Introduction:</b> Primary hyperparathyroidism (PHPT) is mainly caused by parathyroid adenoma (PA). Rare variants of PA, weighing >2.0-3.5 g are called "large" or "giant" adenomas and account for about 1.5% of all PA.</br> <b><br>Aim:</b> The aim of this study was to compare normal-sized and large parathyroid lesions identifying risk factors for severe hypercalcemia.</br> <b><br>Materials and methods:</b> 27 patients with PHPT and parathyroid lesion ≥2.0 cm3 (study group) were compared with 73 patients with PHPT and lesion < 2.0 cm³ (control group). In both groups, the majority were women (81.5% - study group, 90.5% - control group, gender ratios 4.4:9.1, respectively). The patients were examined preoperatively and postoperatively: PTH, creatine, calcium, and phosphate serum and urine concentrations, and calcidiol serum levels were assessed. Preoperative ultrasonography (US) was performed.</br> <b><br>Results:</b> Patients with larger parathyroid lesions had signifficantly higher PTH and calcium serum concentrations and lower serum phosphate and calcidiol concentrations. There were no statistically significant differences in the concentration of creatine in serum and urine, calciuria, or tubular reabsorption of phosphorus (TRP). US relatively underestimated the parathyroid volume by about 0.3-0.4 mL (10% in larger lesions and 43% in smaller ones).</br> <b><br>Conclusions:</b> Due to higher PTH and calcium levels, larger parathyroid adenomas may constitute a higher risk of severe hypercalcemia. In general, US underestimated the parathyroid volume.</br>.

Factors influencing serum calcium levels and the incidence of hypocalcemia after parathyroidectomy in primary hyperparathyroidism patients

Background

Parathyroidectomy (PTX) is an effective treatment for primary hyperparathyroidism (PHPT) patients. Postoperative hypocalcemia is a common complication after PTX. This study aimed to analyze the factors influencing serum calcium levels and the incidence of hypocalcemia after parathyroidectomy in primary hyperparathyroidism patients.

Methods

The retrospective study included 270 PHPT patients treated with PTX and collected their demographic and clinical information and their laboratory indices. Factors influencing serum calcium levels and hypocalcemia after PTX in PHPT patients were analyzed using univariate and multifactorial analyses.

Results

First, in patients with normal preoperative serum calcium levels (2.20-2.74 mmol/L), the higher the preoperative alkaline phosphatase and serum phosphorus levels, the lower the postoperative serum calcium levels. Furthermore, the higher the preoperative serum calcium levels and the accompanying clinical symptoms, the higher the postoperative serum calcium levels. Low preoperative serum calcium levels were shown to be a risk factor for postoperative hypocalcemia (OR=0.022), and the optimal preoperative serum calcium threshold was 2.625 mmol/L (sensitivity and specificity were 0.587 and 0.712, respectively). Second, in the mild preoperative hypercalcemia group (2.75-3.00 mmol/L), the older the patient, the higher the preoperative and postoperative serum calcium levels, the higher the postoperative serum calcium; the lower the alkaline phosphatase and calcitonin levels, the higher the postoperative serum calcium levels. On the other hand, the younger the patient was, the more likely hypocalcemia blood was (OR=0.947), with an optimal age threshold of 47.5 years (sensitivity and specificity were 0.543 and 0.754, respectively). Third, in the preoperative moderate to severe hypercalcemia group (>3.0mmol/L), patients undergoing a combined contralateral thyroidectomy and a total thyroidectomy had low postoperative serum calcium levels.

Conclusion

Patients with different preoperative serum calcium levels had various factors influencing their postoperative serum calcium levels and postoperative hypocalcemia, which facilitated the assessment of their prognosis.

Delayed Diagnosis of Primary Hyperparathyroidism: A Case Report

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

Bilateral giant parathyroid adenoma and hungry bone syndrome: a case report

BACKGROUND

There is some evidence supporting the idea that double parathyroid adenomas represent a different entity from multiglandular hyperplasia; however, the distinction among them is not straightforward.

CASE PRESENTATION

We described a case of primary hyperparathyroidism (PHPT) with pronounced clinical manifestations, caused by a bilateral giant parathyroid adenoma. A 34-year-old Hispanic/Latino male was diagnosed with PHPT caused by two giant parathyroid adenomas. The preoperative tests were neck ultrasound and computed tomography scan (CT-scan), showing two masses in the territory of parathyroid glands, bilaterally distributed (right was 31 × 18 × 19 mm and the left was 38 × 15 × 14 mm); sestamibi scan was not available. Parathyroid hormone (PTH) was highly elevated. Multiple complications of PHPT were present, such as bone lytic lesions, renal and pancreatic calcifications, and cardiovascular disease, the latter of which is an overlooked complication of PHPT. Multiple endocrine neoplasia 1 and 2 (MEN 1/2) were ruled out by the absence of clinical, biochemical, and radiological findings in other endocrine glands. The patient underwent subtotal parathyroidectomy with an intraoperative histopathological study; both intraoperative and definitive histopathology results were consistent with parathyroid adenomas; afterward, adequate suppression of PTH was assured, and later on, the patient presented hungry bone syndrome (HBS).

CONCLUSIONS

The diagnosis of double parathyroid adenomas is difficult. Regarding the similarities between multiglandular hyperplasia and parathyroid adenomas, this case report contributes to the further distinction between these two clinical entities. This case report also represents, in particular, the challenge of difficult diagnosis in places with limited resources, such as developing countries.

Cystic Parathyroid Adenomas as a Risk Factor for Severe Hypercalcemia

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

Safety and diagnostic performance of parathyroid hormone assay in fine-needle aspirate in suspicious parathyroid adenomas

OBJECTIVE

To evaluate the safety and diagnostic performance of parathyroid hormone assay in fine-needle aspirate (PTH-FNA) in patients with primary hyperparathyroidism and suspicious parathyroid adenomas.

METHODOLOGY

A retrospective observational study was performed in 47 patients (57.7 ± 11.2 years of average age, 74% women) attending an endocrinology clinic for primary hyperparathyroidism (average calcemia: 11.6 ± 1.6 mg/dl and PTH: 276 ± 477 pg/mL) in which PTH-FNA was made. Sensibility, specificity, positive predictive value and negative predictive value were calculated in all surgical patients.

RESULTS

Forty-seven lesions were punctured (mean adenoma maximum diameter: 1.8 ± 2.6 cm): negative image in the sestamibi scan (26 patients); the discordance between ultrasonography and the sestamibi scan (6 patients); possible intrathyroidal adenomas (4 patients); a positive sestamibi scan in 2 or more localizations (4 patients); ectopic adenoma (3 patients); persistent primary hyperparathyroidism (2 patients) and atypical adenomas (2 patients). Mean PTH-FNA was 2853 ± 3957 pg/mL and 68% were considered positive (PTH-FNA ≥ 100 pg/mL). No complications were detected during or after the puncture. Thirty-seven patients were operated on, 95% were cured and no parathyromatosis cases were detected. PTH-FNA ≥ 100 pg/mL as a diagnostic test had a sensitivity of 93.7%, a specificity of 100%, a positive predictive value of 100% and an negative predictive value of 71.4%.

CONCLUSION

PTH-FNA is an easy and safe diagnostic test and has a high sensitivity and specificity for differentiating between parathyroid adenomas and other cervical masses in patients with primary hyperparathyroidism.

Factors associated with negative 99mTc-MIBI scanning in patients with primary hyperparathyroidism

OBJECTIVE

The objective was to evaluate the clinical and biological factors associated with negative ^99mTc-MIBI scanning in patients with primary hyperparathyroidism (PHPT).

METHODS

A retrospective observational study was designed in 195 patients (mean age: 59.2 ± 13.0 years; 77% woman) with PHPT (calcium: 11,3 ± 1,1 mg/dl and PTH: 218 ± 295 pg/ml) studied in endocrinology setting between 2013 and 2020. An univariate and multivariate analysis was made to evaluate the clinical and biological factors associated with negative ^99mTc-MIBI scanning.

RESULT

50 patients (26%) with negative ^99mTc-MIBI scanning had lower PTH levels (146 ± 98 vs. 244 ± 334; p < 0,001), adenomas with smaller sonographic dimensions (maximum diameter: 1,2 ± 0,4 vs. 1,7 ± 0,9 cm; p = 0,001 and volume: 0,36 ± 0,43 vs. 1,7 ± 4,1 cm³; p < 0,001), localized more frequently in upper parathyroid glands (37% vs 14%; p = 0,005) and associated more frequently to thyroid nodules (72% vs 57%; p = 0,045) than patients with positive scanning. 116 patients were operated and parathyroid adenomas were smaller (maximum diameter: 1,3 ± 0,5 vs. 1,9 ± 1,1 cm; p = 0,008 and volume: 0,30 ± 0,20 vs. 1,2 ± 1,1 cm³; p < 0,001), less heavy (567 ± 282 vs. 1470 ± 1374 mgr.; p = 0,030) and were localized more frequently in upper situation (65% vs 16%; p < 0,001) than patients with positive scanning. In the multivariate analysis an independent association between negative ^99mTc-MIBI scanning and size of removed adenoma ≤1 cm (OR: 5,77; IC 95: 1,46-22,71) and upper adenoma localization were observed (OR: 8,05; IC 95%: 2,22-29,16).

CONCLUSIONS

One in four patients studied for PHPT had a negative ^99mTc-MIBI scanning and were independent associated with size of adenoma ≤1 cm and upper adenoma localization.

Factors associated with negative 99mTc-MIBI scanning in patients with primary hyperparathyroidism

OBJECTIVE

The objective was to evaluate the clinical and biological factors associated with negative ^99mTc-MIBI scanning in patients with primary hyperparathyroidism (PHPT).

MATERIAL AND METHODS

A retrospective observational study was designed in 195 patients (mean age: 59.2±13.0years; 77% woman) with PHPT (calcium: 11.3±1.1mg/dl and PTH: 218±295pg/ml) studied in endocrinology setting between 2013 and 2020. An univariate and multivariate analysis was made to evaluate the clinical and biological factors associated with negative ^99mTc-MIBI scanning.

RESULTS

50 patients (26%) with negative ^99mTc-MIBI scanning had lower PTH levels (146±98 vs. 244±334; p<0.001), adenomas with smaller sonographic dimensions (maximum diameter: 1.2±0.4 vs. 1.7±0.9cm; p=0.001 and volume: 0.36±0.43 vs. 1.7±4.1cm³; p<0.001), localized more frequently in upper parathyroid glands (37% vs. 14%; p=0.005) and associated more frequently to thyroid nodules (72% vs. 57%; p=0.045) than patients with positive scanning. 116 patients were operated and parathyroid adenomas were smaller (maximum diameter: 1.3±0.5 vs. 1.9±1.1cm; p=0.008 and volume: 0.30±0.20 vs. 1.2±1.1cm³; p<0.001), less heavy (567±282 vs. 1470±1374mg; p=0.030) and were localized more frequently in upper situation (65% vs. 16%; p<0.001) than patients with positive scanning. In the multivariate analysis an independent association between negative ^99mTc-MIBI scanning and size of removed adenoma ≤1cm (OR: 5.77; 95% CI: 1.46-22.71) and upper adenoma localization were observed (OR: 8.05; 95% IC: 2.22-29.16).

CONCLUSIONS

One in four patients studied for PHPT had a negative ^99mTc-MIBI scanning and were independent associated with size of adenoma ≤1cm and upper adenoma localization.

Primary hyperparathyroidism is associated with a higher level of serum uric acid: A systematic review and meta-analysis

OBJECTIVES

Studies have suggested that primary hyperparathyroidism could be a risk factor for hyperuricemia although the results were not consistent across the studies. This systematic review and meta-analysis was performed in order to identify all available studies and summarize their results together.

METHODS

A systematic review was performed using EMBASE and MEDLINE from inception to August 2018 to identify all cohort studies that consisted of 2 cohorts, a cohort of patients with primary hyperparathyroidism and a cohort of individuals without hyperparathyroidism. Eligible studies had to provide data on mean serum uric acid level and standard deviation of both cohorts, which would be extracted to calculate mean difference (MD). Pooled MD was then calculated by combining MDs of each study using a random-effects model. Funnel plot was used for evaluation for publication bias.

RESULTS

A total of 9 cohort studies met the inclusion criteria and were included into the meta-analysis. The pooled analysis found that patients with primary hyperparathyroidism had a significantly higher level of serum uric acid than individuals without hyperparathyroidism with the pooled MD of 65.00 μmol/L (95% CI 37.74-92.25). The statistical heterogeneity was high with I² of 90%. The funnel plot was relatively symmetric and did not provide evidence for publication bias.

CONCLUSION

Patients with primary hyperparathyroidism had a significantly higher level of serum uric acid compared to individuals without hyperparathyroidism.

Parathyroid Hormone Fragments: New Targets for the Diagnosis and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder

As a common disorder, chronic kidney disease (CKD) poses a great threat to human health. Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a complication of CKD characterized by disturbances in the levels of calcium, phosphorus, parathyroid hormone (PTH), and vitamin D; abnormal bone formation affecting the mineralization and linear growth of bone; and vascular and soft tissue calcification. PTH reflects the function of the parathyroid gland and also takes part in the metabolism of minerals. The accurate measurement of PTH plays a vital role in the clinical diagnosis, treatment, and prognosis of patients with secondary hyperparathyroidism (SHPT). Previous studies have shown that there are different fragments of PTH in the body's circulation, causing antagonistic effects on bone and the kidney. Here we review the metabolism of PTH fragments; the progress being made in PTH measurement assays; the effects of PTH fragments on bone, kidney, and the cardiovascular system in CKD; and the predictive value of PTH measurement in assessing the effectiveness of parathyroidectomy (PTX). We hope that this review will help to clarify the value of accurate PTH measurements in CKD-MBD and promote the further development of multidisciplinary diagnosis and treatment.