Utility of parathyroid hormone immunocytochemistry in fine needle aspiration diagnosis of parathyroid tissue.

OBJECTIVE: The cytomorphological features of parathyroid tissue (PTT) may overlap with those of thyroid lesions, thus posing a diagnostic challenge. In this retrospective study, we reviewed our institutional experience in using parathyroid hormone (PTH) immunocytochemistry (ICC) to substantiate the diagnosis of PTT on fine needle aspiration (FNA). METHODS: Our pathology database was searched for FNA cases in which PTH ICC was performed between 1 January 2015 and 31 March 2022. PTH ICC was performed on a ThinPrep slide in cases with a clinical suspicion of PTT or with cytomorphological features raising the possibility of PTT. Patients' clinicopathological characteristics, PTH ICC results, cytological diagnoses, and surgical follow-ups, if available, were reviewed and analysed. RESULTS: The study cohort included 103 cases clinically designated as thyroid (n = 85, 82.5%), parathyroid (n = 11, 10.7%) and neck soft tissue (n = 7, 6.8%). PTH immunostaining was negative, positive, and indeterminate in 53 (51.5%), 27 (26.2%), and 23 (22.3%) cases, respectively. Surgical follow-up was available in 27 (26.2%) cases, including 17 thyroid lesions and 10 PTT cases. All positive PTH cases were confirmed to be PTT, while all but one of the negative PTH cases were non-PTT on follow-up. The calculated sensitivity, specificity, positive and negative predictive values were 85.7%, 100%, 100% and 93.3%, respectively. CONCLUSION: Our study demonstrates that PTH ICC performed on additional ThinPrep slides is a valuable adjunct test in FNA samples with a differential diagnosis of PTT vs non-PTT. Low cellularity may be a limiting factor in the accurate assessment of PTH by ICC.

Parathyroid hormone in situ measurement in patients with hyperparathyroidism: single-centre experience of 179 patients.

Context: The measurement of parathyroid hormone(PTH) in situ (PTHis) by fine-needle aspiration (FNA) has been proposed as a tool to preoperatively help localize parathyroid glands detected on ultrasound. However, the accuracy of PTHis is highly variable according to the few available studies. Aim: We aimed to develop and validate the PTHis procedure and assessed the performance of PTHis in a large series of patients with hyperparathyroidism and/or undetermined cervical lesions. Patients and methods: The technique set-up consisted of PTHis measurement in thyroid samples from patients with thyroid nodules and patients with high circulating PTH levels (tertiary hyperparathyroidism). Consecutive patients were recruited at one tertiary referral centre from 2017 to 2020 and submitted to ultrasound-guided FNA-PTHis determination. Results: During the method set-up, we obtained undetectable PTHis levels in all non-parathyroid tissues after sample dilutions. PTHis was higher in patients with hyperparathyroidism (n = 145; 1817 ± 3739 ng/L; range: <4.6-31 140) than in those with thyroid or undetermined cervical lesions (n= 34; <4.6 ng/mL; P < 0.0001). When evaluating PTHis performance in histologically proven samples (158 lesions from 121 patients), PTHis was detectable in 85/97 parathyroid lesions (87%; range: 22-31;140 ng/L) and undetectable in all non-parathyroid lesions (n = 61; P < 0.0001). The specificity and positive predictive value were 100%, and the sensitivity was 87.6%. False-negative lesions (n= 12) were smaller (9.4 ± 5.9 mm) and more often consisted of hyperplasias (75%) than true-positive lesions (16.1 ± 8.4 mm and 33%, P = 0.009 and P = 0.0089, respectively). The method was safe and well tolerated. Four educational cases are also provided. Conclusions: PTHis determination is a safe and well-tolerated procedure that enhances the specificity of ultrasound-detected lesions. If accurately set-up, it confirms the parathyroid origin of uncharacterized cervical lesions.

Use of the parathyroid hormone assay at H6 post thyroidectomy: an early predictor of hypocalcemia.

PURPOSE: Hypocalcemia linked to a diminished circulating intact parathormone (iPTH) is the most common complication after total thyroidectomy. The objective of this study was to evaluate iPTH as a predictor of post-thyroidectomy hypocalcemia. METHODS: Hundred-and-eight patients who underwent total thyroidectomy were included. Blood samples (iPTH, calcium and albumin) were performed at different times: preoperatively (H0), after removal of the gland (Hdrop), 6 h (H6) and one day (D1) after the surgery. Hypocalcemia was defined by total calcium corrected by serum albumin ≤ 2.10 mmol/l. The area under the ROC curve (AUC) was used to determine the best cut-off value and predictability of iPTH for hypocalcemia in terms of absolute value (ng/L), decrease in the slope (ng/L) and decline (%) between two times. RESULTS: The study included 101 patients. Among them, 39 had hypocalcemia (38.6%). At H6, an iPTH absolute value less than 14.35 ng/L (Se = 0.706; Sp = 0.917) and a decline from the preoperative time of more than 59.5% (Se = 0.850; Sp = 0.820) were predictive of hypocalcemia. Other absolute values, decrease in the sloop and decline between preoperative and postoperative values were less relevant. CONCLUSION: The iPTH 6 h after total thyroidectomy is predictive of hypocalcemia. It might be used to identify patients not at risk of hypocalcemia and earlier discharge could be considered.

Challenging NICE guidelines on parathyroid surgery.

BACKGROUND: National Institute of Clinical Excellence (NICE) recommend against routinely using Intra-Operative Parathyroid Hormone (IOPTH) for first-time parathyroid surgery due to its cost and minimal surgical benefit. The European Society of Endocrine Surgeons differ from this and recommends IOPTH with conflicting pre-operative or single imaging. NICE guidance acknowledged that this may change practice in larger centres. We devised a retrospective single-centre cohort study to analyse the impact of IOPTH on decision-making and cost-effectiveness. METHODOLOGY: First-time parathyroidectomy procedures for primary hyperparathyroidism were assessed between 2017 and 2019. Ultrasound (US) and Sestamibi with parathyroid single-photon emission with computed tomography (SPECT-CT) were compared with IOPTH. The contribution of IOPTH to cure and cost effectiveness ratio was calculated. RESULTS: 114 cases were included, with IOPTH performed in all cases, SPECT-CT in 112 and US in 108 cases. A cure rate of 99.1% (113/114) was achieved. 11.4% (13/114) of the cure rate was influenced by IOPTH (P 0.01), instigating further exploration when its levels didn't decrease. This included 7.1% (4/56) in the concordant-imaging cohort. IOPTH accuracy (96.5%) was significantly superior (P = 0.03) to both US (80%) and SPECT-CT (81%). Comparing the total costs for IOPTH testing over 2 years (£39,721) with 13 potential re-operative procedures in its absence (£63,536), a positive cost-effectiveness ratio of £1832 per re-operative procedure averted was achieved. CONCLUSION: Abandoning IOPTH in first-time parathyroid surgery is too ambitious when weighing the cost of re-operative surgery against cost savings obtained by using routine IOPTH to achieve an improved cure rate, even in concordant imaging.

Crisis hipercalcémica, presentación inusual de adenoma paratiroideo: reporte de 2 casos / Hypercalcemic crisis, unusual presentation of parathyroid adenoma

La crisis hipercalcémica (CH) es una emergencia endocrina inusual, definida por la presencia de calcemia > 14 mg/dl asociada a disfunción renal, alteraciones cardiovasculares, gastrointestinales y del sensorio; también podría considerarse en pacientes con síntomas graves y calcemia menor. El hiperparatiroidismo primario (HPTP) y las neoplasias malignas son las etiologías más comunes de la hipercalcemia (90% de los casos); sin embargo, rara vez el primero se presenta como CH. Debido a la alta mortalidad asociada a esta entidad, es de gran importancia establecer diagnóstico y tratamiento precoces. Presentamos dos pacientes con crisis hipercalcémica como primera manifestación del HPTP, el 1.° con bloqueo auriculoventricular (AV) completo y el 2.° con pancreatitis aguda. La anatomía patológica (AP) reveló adenoma oxifílico en ambos casos, que es una variante histológica poco frecuente y puede manifestarse clínicamente de forma grave. Conclusiones: los adenomas paratiroideos son causa poco frecuente de CH. Consideramos el tipo histológico observado (adenoma oxifílico) como probable factor condicionante. La pancreatitis y especialmente el bloqueo AV son manifestaciones poco frecuentes de la CH. Resaltamos la importancia de la determinación de los niveles de calcio dentro de la evaluación inicial de todo paciente con bloqueo AV. (AU)

Hypercalcemic crisis (HC) is an unusual endocrine emergency, defined as the presence of serum calcium > 14 mg/dl related to kidney dysfunction, cardiovascular, gastrointestinal and sensory disturbances. It could also be considered in patients with severe symptoms and lower serum calcium levels. Primary hyperparathyroidism (PHPT) and malignant neoplasms are the most common hypercalcemia etiologies (90% of cases), nevertheless, the former hardly ever occurs as HC. Due to the high mortality associated with HC, it is crucial to establish early diagnosis and treatment.We report two patients with HC as the first manifestation of PHPT; the former with atrioventricular (AV) block and the latter with acute pancreatitis. Pathology revealed oxyphilic adenoma in both cases, which is an infrequent histological variant that can have a severe clinical manifestation. Conclusions: parathyroid adenomas are a rare cause of HC. We consider the histological type observed (oxyphilic adenoma) as a probable conditioning factor. Pancreatitis and especially AV block are rare manifestations of HC. We emphasize the importance of determining calcium levels in the initial evaluation of all patients with AV block. (AU)

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 ±â€¯11.2 years of average age, 74% women) attending an endocrinology clinic for primary hyperparathyroidism (average calcemia: 11.6 ±â€¯1.6 mg/dl and PTH: 276 ±â€¯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 ±â€¯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 ±â€¯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.

Concentrations of Ca, Mg, P, Prostaglandin E2 in Bones and Parathyroid Hormone; 1,25-dihydroxyvitamin D3; 17-ß-estradiol; Testosterone and Somatotropin in Plasma of Aging Rats Subjected to Physical Training in Cold Water.

Exposure to low temperatures can be considered a stressor, which when applied for a specific time can lead to adaptive reactions. In our study we hypothesized that cold, when applied to the entire body, may be a factor that positively modifies the aging process of bones by improving the mechanisms related to the body's mineral balance. Taking the above into account, the aim of the study was to determine the concentration of calcium (Ca), magnesium (Mg), and phosphorus (P) in bones, and to examine bone density and concentrations of the key hormones for bone metabolism, namely parathyroid hormone (PTH), somatotropin (GH), 1,25-dihydroxyvitamin D3, 17-ß estradiol, testosterone (T) in plasma, and prostaglandin E2 (PGE2) in the bone of aging rats subjected to physical training in cold water. The animals in the experiment were subjected to a series of swimming sessions for nine weeks. Study group animals (male and female respectively) performed swimming training in cold water at 5 ± 2 °C and in water with thermal comfort temperature (36 ± 2 °C). Control animals were kept in a sedentary condition. Immersion in cold water affects bone mineral metabolism in aging rats by changing the concentration of Ca, Mg, and P in the bone, altering bone mineral density and the concentration of key hormones involved in the regulation of bone mineral metabolism. The effect of cold-water immersion may be gender-dependent. In females, it decreases Ca and Mg content in bones while increasing bone density and 17-ß estradiol and 1,25-dihydroxyvitamin D3 levels, and with a longer perspective in aging animals may be positive not only for bone health but also other estrogen-dependent tissues. In males, cold water swimming decreased PTH and PGE2 which resulted in a decrease in phosphorus content in bones (with no effect on bone density), an increase in 1,25-dihydroxyvitamin D3, and increase in T and GH, and may have positive consequences especially in bones and muscle tissue for the prevention of elderly sarcopenia.

Intra-operative parathyroid hormone evaluation is superior to frozen section analysis in parathyroid surgery.

BACKGROUND: Surgery is currently the only treatment option for patients with primary hyperparathyroidism (PHPT). Recently, minimally invasive parathyroidectomy (MIP) has begun to replace traditional bilateral neck exploration (BNE). OBJECTIVE: The aim of this study is to compare the results of parathyroidectomies performed in our hospital over the past decade that were guided by intra-operative parathyroid hormone (IOPTH) sampling or frozen section (FS) analysis. MATERIAL AND METHODS: Data on 697 patients who underwent parathyroidectomies in the Department of Endocrine Surgery, Dokuz Eylul University between January 2005 and 2018 were included in this study. Patients with malignancies other than thyroid papillary microcarcinoma and parathyroid cancer were excluded from the study. RESULTS: The concomitant use of neck ultrasound (US) and technetium 99m Sestamibi (99mTc MIBI) scintigraphy successfully localized the hyperfunctioning parathyroid glands in nearly 96% of cases. As compared with the IOPTH group, the operation time was longer in the FS group (p < 0.001), and the need for postoperative calcium (Ca) supplementation was higher (p < 0.001). The duration of hospitalization (days) was significantly higher in the FS group (4.2 ± 3.4 vs. 2.6 ± 1.9) as compared with that in the IOPTH group (p < 0.001). In addition, the recurrence rate in the FS group was significantly higher than that in the IPOTH group (p = 0.002). CONCLUSION: IOPTH sampling is a safe and effective method when performed by experienced surgeons and with appropriate preoperative screening. This study emphasizes that IOPTH sampling. We believe that the success in parathyroid surgery is due to three factors: correct indication, accurate localization and experienced surgeon.

The changing face of reoperative parathyroidectomy: a single-centre comparison of 147 parathyroid reoperations.

INTRODUCTION: Reoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies. MATERIALS AND METHODS: Retrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B). RESULTS: From over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B. CONCLUSION: Optimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.

Biomarkers of Bone Turnover Identify Subsets of Chronic Kidney Disease Patients at Higher Risk for Fracture.

BACKGROUND: We sought to identify biomarkers that indicate low turnover on bone histomorphometry in chronic kidney disease (CKD) patients, and subsequently determined whether this panel identified differential risk for fractures in community-dwelling older adults. METHODS: Among CKD patients who underwent iliac crest bone biopsies and histomorphometry, we evaluated candidate biomarkers to differentiate low turnover from other bone disease. We applied this biomarker panel to 641 participants in the Health Aging and Body Composition Study (Health ABC) study with estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2 who were followed for fracture. Cox proportional hazards models evaluated the association of bone mineral density (BMD) with fracture risk and determined whether biomarker-defined low bone turnover modified fracture risk at any level of BMD. RESULTS: In 39 CKD patients age 64 ± 13 years, 85% female, with mean eGFR 37 ± 14 mL/min/1.73 m2 who underwent bone biopsy, lower fibroblast growth factor (FGF)-23, higher ɑ-Klotho, and lower parathyroid hormone (PTH) indicated low bone turnover in accordance with bone histomorphometry parameters (individual area under the curve = 0.62, 0.73, and 0.55 respectively; sensitivity = 22%, specificity = 100%). In Health ABC, 641 participants with CKD were age 75 ± 3 years , 49% female, with mean eGFR 48 ± 10 mL/min/1.73 m2. For every SD lower hip BMD at baseline, there was an 8-fold higher fracture risk in individuals with biomarker-defined low turnover (hazard ratio 8.10 [95% CI, 3.40-19.30]) vs a 2-fold higher risk in the remaining individuals (hazard ratio 2.28 [95% CI, 1.69-3.08]) (Pinteraction = .082). CONCLUSIONS: In CKD patients who underwent bone biopsy, lower FGF-23, higher ɑ-Klotho, and lower PTH together had high specificity for identifying low bone turnover. When applied to older individuals with CKD, BMD was more strongly associated with fracture risk in those with biomarker-defined low turnover.

Autosomal dominant hypocalcaemia: identification of two novel variants of CASR gene.

Autosomal dominant hypocalcaemia is a rare aetiology of hypocalcaemia, caused by gain-of-function mutations of the calcium-sensing receptor (CASR) gene. We present two cases of two asymptomatic women (50-year-old-case 1 and 25-year-old-case 2), referred to our endocrinology department for investigation of hypocalcaemia, hyperphosphatemia and inappropriately low parathormone. Both patients had relatives with the same laboratorial findings. At diagnosis, both patients presented basal ganglia calcifications. Genetic analysis was performed, identifying two novel heterozygous CASR variants: c.2269G>A (p.Glu757Lys) and c.2086C>G (p.Leu696Val), respectively, for case 1 and case 2. Affected individuals started oral calcium and vitamin D analogues, aiming to a low-normal calcium level. They remain under observation and are asymptomatic.

Fine-needle aspiration with rapid parathyroid hormone assay to identify parathyroid gland in thyroidectomy.

To determine the levels of parathyroid hormone (PTH) in the fluids of various tissues for identification of parathyroid glands during thyroidectomy.Our study comprised 31 patients with thyroid cancer who underwent lobectomy with central compartment dissection at our hospital from October 2014 to February 2015. A total of 186 tissue samples, including 28 from parathyroid glands and 158 from non-parathyroid tissues, were obtained during the operations. Tissue fluids were collected via fine-needle aspiration to measure PTH levels; the tissue was punctured 3 times with a 26-gauge syringe needle and washed with 0.5 mL normal saline. Tissues were also prepared for pathological examination.PTH concentrations were significantly higher in parathyroid tissues than non-parathyroid tissues. None of the patients had irremediable parathyroid dysfunction after surgical resection.Use of fine-needle aspiration for quantification of PTH levels in tissue fluids rapidly, safely, and effectively identifies the parathyroid glands during thyroidectomy.

Association of parathormone and alkaline phosphatase with bone turnover and mineralization in children with CKD on dialysis: effect of age, gender, and race.

BACKGROUND: Studies investigating bone histology in children with chronic kidney disease (CKD) are scarce. METHODS: Forty-two patients, mean age 11.3 ± 4.3 years with stage 5 CKD on dialysis, underwent double tetracycline labeling bone biopsy and the relationship between clinical features, biochemical markers, and bone densitometry (DXA) was investigated. RESULTS: Low bone turnover was present in 59% of patients, abnormal mineralization in 29%, and low bone volume in 7%. Higher bone formation rate was found in non-Caucasian patients, whereas abnormal mineralization occurred in older and shorter children. We found no impact of gender and etiology of renal disease in our population. Parathormone (PTH) and alkaline phosphatase (AP) showed positive associations with bone turnover. ROC curve analysis showed a fair performance of biomarkers to predict TMV status. PTH < 2 times ULN independently associated with low bone turnover (RR 5.62, 95% CI 1.01-31.24; p = 0.049), in a model adjusted for race, calcitriol dosage, and calcium. It was also associated with abnormal mineralization (RR 1.35, 95% CI 1.04-1.75; p = 0.025), in a model adjusted for BMD scores, AP, age, and calcitriol. PTH and AP significantly predicted turnover and mineralization defect, although with low specificity and sensitivity, reaching a maximum value of 64% and 67%, respectively. CONCLUSIONS: While PTH and AP were associated with turnover and mineralization, we recognize the limitation of their performance to clearly distinguish high from low/normal bone turnover and normal from abnormal mineralization. Our results reinforce the need to expand knowledge about renal osteodystrophy in pediatric population through prospective bone biopsy studies. Graphical abstract.

Influence of common clinical variables on intraoperative parathyroid hormone monitoring during surgery for primary hyperparathyroidism.

BACKGROUND: Intraoperative monitoring of parathyroid hormone (IOPTH) is a reliable method of predicting the cure of primary hyperparathyroidism (PHPT). The aim of this study is to assess whether common clinical variables (CCV) frequently encountered in patients with PHPT may affect the magnitude of PTH drop or the likelihood of patients meeting the intraoperative cure criterion. DESIGN: Patients who were surgically cured from PHPT caused by single gland disease (SGD) and had full IOPTH protocol (4 measurements) were stratified according to age, gland weight, renal function, vitamin D status and severity of hypercalcemia. The percentage of IOPTH drop and the frequency of patients who had true positive IOPTH test results were compared among groups. RESULTS: 762 patients had surgery for PHPT, of whom 746 were (98%) cured. Of these 746 patients, 511 who had SGD and a full IOPTH protocol were included in this study. The median IOPTH drop was significantly higher among younger patients, those with severe hypercalcaemia at 5, 10, 15 min after gland excision, giant glands (at 5-min only), patients with vitamin D deficiency (at 10, 15 min), and those with normal renal function (at 15 min only). The likelihood of the patients meeting the intraoperative cure criterion was not significantly affected among the groups except in patients with mild hypercalcaemia, who were significantly less likely to have 50% IOPTH drop than those with severe hypercalcaemia at all time points. The frequency of mildly hypercalcaemic patients who met cure criterion was significantly improved by extending measurement to 15 min. CONCLUSIONS: IOPTH monitoring has the ability to mitigate the variability of IOPTH kinetics associated with most clinical variables. Mildly hypercalcemic patients in particular may benefit from waiting for 15-min measurement before any surgical decision is made.

Surgical treatment in patients with single and multiple gland primary hyperparathyroidism with the use of intraoperative parathyroid hormone monitoring: extensive single-center experience.

PURPOSE: To evaluate a single-center extensive experience and effectiveness in surgical treatment of primary hyperparathyroidism (pHPT) with the use of rapid intraoperative parathyroid hormone (ioPTH) monitoring in patients with single gland (SGpH) or multiple gland (MGpH) disease. METHODS: This retrospective, single-center cohort study included 214 patients with pHPT treated from January 2010 to June 2017. In total, 172 patients fulfilled the inclusion criteria having at least one preoperative localization image study and measurement of ioPTH. Statistical analysis was made by the chi-square test and Student's t tests. RESULTS: Of the 172 patients, 146 were women (85%) and 26 men (15%), with a mean age of 56.9 years; 153 (89%) had SGpH and 19 (11%) MGpH. The mean follow-up was 41.8 months. A total of 153 surgical procedures were performed as minimal invasive parathyroidectomy (MIP) based on a SGpH diagnosis; operative success was achieved in 150 cases (98%), according to ioPTH concentrations. The remainder (19 procedures) were performed as bilateral neck exploration (BNE) based on a MGpH diagnosis; operative success was achieved in 16 cases (84%). ioPTH correctly modified the initially planned operation in 26.3% of patients with MGpH. CONCLUSIONS: ioPTH enables the surgical treatment of patients with pHPT with focused approaches and excellent results, as it helps the surgeon to identify cases of MGpH. ioPTH adds value to cases where preoperative imaging failed to detect the affected gland or the results are inconclusive. According to the literature, its application seems to be of marginal benefit in cases in which there are two concordant preoperative imaging studies.

The Influence of Different Cholecalciferol Supplementation Regimes on 25(OH) Cholecalciferol, Calcium and Parathyroid Hormone after Bariatric Surgery.

Background and objectives: Vitamin D is an essential vitamin that plays a key role in maintaining physiological calcium balance, and is also a pivotal element in the formation of bone structure. Vitamin D deficiency is associated with a wide array of clinical symptoms. Vitamin and mineral deficiencies are quite common prior to and after bariatric surgery, and therefore we have evaluated the effects of two different cholecalciferol supplementation regimes on serum calcium, 25(OH) cholecalciferol, and parathyroid hormone (PTH). Materials and Methods: In this retrospective matched cohort study, two different cholecalciferol supplementation regimes were compared. Group A consisted of 50 patients who had 1000 mg calcium and 800 IU cholecalciferol. In Group B, 50 patients had 1000 mg calcium and 800 IU cholecalciferol with an additional 1 ml liquid cholecalciferol (50,000 IU) monthly. The primary outcome was the effects on blood serum levels of calcium, 25(OH) cholecalciferol, and PTH. Results: In group A and group B, there were significant increases in 25(OH) cholecalciferol, with a higher delta in favor of group B (for all three p < 0.001). A decrease was seen in PTH (p < 0.001), and no differences were measured in calcium levels in both groups. Conclusion: Our study suggests that an additional 1 ml cholecalciferol (50,000 IU) monthly can result in less biochemically 25(OH) cholecalciferol deficient patients after bariatric surgery. No effects were seen on the calcium balance. However, larger randomized clinical trials need to be done to assess the effects on clinical outcomes like bone health and fracture risk.

Tenofovir Has Minimal Effect on Biomarkers of Bone Health in Youth with HIV Receiving Initial Antiretroviral Therapy.

Both HIV infection and tenofovir disoproxil fumarate (TDF) treatment adversely impact bone metabolism and may lead to osteopenia, which has critical implications for youth with HIV (YWH). This study evaluates changes in the biomarkers of bone metabolism and inflammation among YWH receiving initial treatment with TDF- and non-TDF-containing antiretroviral therapies (ARTs). YWH [n = 23, median age 21 years (range 18-24), 87% male, 61% African American] were assessed for inflammatory and bone metabolism biomarkers at enrollment, after 48 weeks of TDF-containing ART, and 96 weeks of ART without TDF with continued viral suppression. Spearman's rank correlation evaluated biomarker associations. Bone alkaline phosphatase, parathyroid hormone, and osteopontin increased after TDF treatment. All fell after TDF was discontinued. Levels of RANKL and osteoprotegerin did not change throughout the study. There was little correlation between biomarkers of bone metabolism and either macrophage or lymphocyte activation at any time point. Our results establish baseline associations between bone metabolism and immune biomarkers for this population, and find that before CD4 T cell decline chronic inflammation does not perturb biomarkers of bone metabolism among YWH. The adverse effects of TDF on bone health may be marginal for YWH at the early stages of disease.

Parathyroid Neoplasms: Immunohistochemical Characterization and Long Noncoding RNA (lncRNA) Expression.

Parathyroid adenomas are slow growing benign neoplasms associated with hypercalcemia, while atypical parathyroid adenomas and parathyroid carcinomas are uncommon tumors and their histologic features may overlap with parathyroid adenomas. LncRNAs participate in transcription and in epigenetic or post-transcriptional regulation of gene expression, and probably contribute to carcinogenesis. We analyzed a group of normal, hyperplastic, and neoplastic parathyroid lesions to determine the best immunohistochemical markers to characterize these lesions and to determine the role of selected lncRNAs in tumor progression. A tissue microarray consisting of 111 cases of normal parathyroid (n = 14), primary hyperplasia (n = 15), secondary hyperplasia (n = 10), tertiary hyperplasia (n = 11), adenomas (n = 50), atypical adenomas (n = 7), and carcinomas (n = 4) was used. Immunohistochemical staining with antibodies against chromogranin A, synaptophysin, parathyroid hormone, and insulinoma-associated protein 1(INSM1) was used. Expression of lncRNAs including metastasis-associated lung adenocarcinoma transcript one (MALAT1), HOX transcript antisense intergenic RNA (HOTAIR), and long intergenic non-protein coding regulator of reprograming (Linc-ROR or ROR) was also analyzed by in situ hybridization and RT-PCR. All of the parathyroid tissues were positive for parathyroid hormone, while most cases were positive for chromogranin A (98%). Synaptophysin was expressed in only 12 cases (11%) and INMS1 was negative in all cases. ROR was significantly downregulated during progression from normal, hyperplastic, and adenomatous parathyroid to parathyroid carcinomas. These results show that parathyroid hormone and chromogranin A are useful markers for parathyroid neoplasms, while synaptophysin and INSM1 are not very sensitive broad-spectrum markers for these neoplasms. LincRNA ROR may function as a tumor suppressor during parathyroid tumor progression.