iPTH Levels Research Articles

Effectiveness and Safety of Ultrasound-Guided Local Paricalcitol Injection in Treating Secondary Hyperparathyroidism in ESRD: A Retrospective Study.

To compare the safety and efficacy of percutaneous paricalcitol injection with intravenously administered paricalcitol in treating parathyroid hyperplasia in patients with secondary hyperparathyroidism (SHPT). This study was approved by the Ethics Committee of our institution. We retrospectively collected data on patients who received percutaneous paricalcitol injection (24 patients) and intravenously administered paricalcitol (22 patients) based on their intact parathyroid hormone (iPTH) level. Serum iPTH, calcium, phosphorus, and the volume of the parathyroid gland were measured at several indicated time points after treatment, and adverse events associated with the two treatments were evaluated. After 6 months of follow-up, we found that patients from the percutaneous injection group had significantly decreased levels of iPTH (from 1887.81 ± 726.81 pg/mL to 631.06 ± 393.06 pg/mL), phosphate (from 1.94 ± 0.36 mmol/L to 1.71 ± 0.34 mmol/L), and volume of the parathyroid gland (from 0.87 ± 0.50 cm3 to 0.60 ± 0.36 cm3), with relief from ostealgia within 48-72 h. In the intravenously administered group, the levels of iPTH decreased from 686.87 ± 260.44 pg/mL to 388.47 ± 167.36 pg/mL; while there was no significant change in phosphate levels, the volume of the parathyroid gland and ostealgia relief were observed at the end of follow-up. The serum calcium level did not significantly change, and no severe complications were observed in both groups. In vitro fluorescence-activated single cell sorting (FACS) analysis indicated that paricalcitol induced parathyroid cell apoptosis in a dose-dependent manner. Percutaneous paricalcitol injection is a selective treatment for SHPT in ESRD.

Optimal Serum 25(OH)D Level and Vitamin D Intake in Young Korean Women.

Vitamin D status is essential for preventing bone disease. Young Korean women have the highest vitamin D deficiency prevalence compared with other demographic groups. This study aimed to establish the optimal vitamin D intake level for maintaining an adequate serum 25-hydroxyvitamin D (25[OH]D) level by season in young Korean women (mean age: 23.1 years). Each participant (wintertime, n = 101; summertime, n = 117) completed a lifestyle survey, dietary record, bone mineral density, and biochemical tests. Seasonal factors impacting 25(OH)D were identified, vitamin D intake for sufficient 25(OH)D levels was calculated, and the relationship between 25(OH)D and intact parathyroid hormone (iPTH) was analyzed. During summertime, 25(OH)D levels were higher than in wintertime (17.9 vs. 15.0 ng/mL). A 1 µg/1000 kcal increase in vitamin D intake increased 25(OH)D levels by 0.170 ng/mL in wintertime and 0.149 ng/mL in summertime. iPTH levels reached a theoretical plateau corresponding to an 18.4 ng/mL 25(OH)D level. The vitamin D intake threshold for maintaining 25(OH)D levels at ≥20 and ≥18.4 ng/mL was ≥10.97 μg/day. For a sufficient level of 25(OH)D in young Korean women, increasing summertime UV irradiation time and increasing vitamin D supplements and vitamin D-containing foods throughout the year is beneficial.

Effect of total parathyroidectomy in patients with secondary hyperparathyroidism: a retrospective study

PurposeTo investigate the therapeutic efficacy, feasibility, and safety of total parathyroidectomy (tPTX) in the treatment of secondary hyperparathyroidism (SHPT).MethodsThe clinical data of 34 SHPT patients admitted to the Department of Nephrology, Yuxi People’s Hospital, from January 2018 to January 2021 who had received tPTX, were retrospectively analyzed. The indications for tPTX were severe SHPT that did not respond to medical treatment and was ineligible for kidney transplantation. tPTX without autotransplantation was adopted to compare the level of symptom relief and changes in serum intact parathyroid hormone (iPTH), blood calcium, and blood phosphorus pre- and postoperatively.ResultsIn 34 patients, 142 parathyroid glands were removed, including 21 ectopic parathyroid glands (14.78%). Six patients (17.64%, 6/34) had supernumerary parathyroid glands. At 6 h postoperatively, arthralgia and bone pain were significantly reduced to almost zero in 94.12% (32/34) of patients. At 24 h postoperatively, relief of bone pain and improvement of limb movement were observed in 100% (34/34) of patients, and pruritus almost disappeared in 86.36% (19/22) of patients. There were significant differences in iPTH (χ2 = 134.93, P < 0.05), calcium (χ2 = 23.02, P < 0.05), and phosphorus (χ2 = 102.11, P < 0.05) levels preoperatively and 40 min, 24 h, 1 week, half a year, and last available (> 1 year) postoperatively.The patients were followed up for 15–47 months (median 33 months). Hypoparathyroidism was observed in three patients, who underwent neck dissection or partial thymotomy concurrently for different reasons. No intractable hypocalcemia or adynamic bone disease occurred during the follow-up period.ConclusionIn SHPT patients who were ineligible for renal transplantation, tPTX was effective, safe, and reliable, with a low recurrence rate. However, when tPTX was performed alone without autologous transplantation, bilateral neck exploration was sufficient, and central neck dissection and thymic resection were inadvisable.

Determinants of Secondary Hyperparathyroidism 1 Year After One-Anastomosis Gastric Bypass or Sleeve Gastrectomy.

Bariatric surgery alters the anatomic and physiological structure of the gastrointestinal tract, predisposing patients to the malabsorption of nutrients. The purpose of this study was to determine the prevalence and determinants of secondary hyperparathyroidism (SHPT) in the patients undergoing either one-anastomosis gastric bypass (OAGB) or sleeve gastrectomy (SG). A total of 517 patients (without SHPT at the baseline) who had undergone OAGB or SG were prospectively assessed 1year after the surgery. Anthropometric parameters, calcium, intact parathyroid hormone (iPTH), and 25(OH)D levels were compared according to the surgery type before and 1year after surgery. Multiple logistic regression models were used to evaluate possible SHPT predictors after bariatric surgery. The overall prevalence of SHPT was 12.6% after surgery, significantly different between the OAGB and SG groups (17.1 vs. 9.9%, respectively). The serum levels of albumin-corrected calcium and 25(OH)D were not significantly different between the two groups. The patients undergoing OAGB had significantly higher serum levels of ALP (198.2 vs. 156.6) compared to the subjects undergoing SG. Higher iPTH levels preoperatively, lower 1-year excess weight loss%, and OAGB surgery seemed to be independent predictors for SHPT 1year after surgery. Morbidly-obese patients undergoing OAGB had a higher risk of SHPT than their counterparts undergoing SG, whereas 25(OH)D deficiency and calcium levels did not differ between the two groups. The OAGB procedure, preoperative iPTH levels, and 1-year weight loss were predictors of postoperative SHPT development.

Reoperation treatment of persistent postoperative secondary hyperparathyroidism

Objective:To evaluate the clinical effect of reoperation in persistent hyperparathyroidism （PHPT） patients after operation of parathyroidectomy combined with autotransplantation（PTX+AT） on secondary hyperparathyroidism （SHPT） . Methods:18 PHPT patients who treated with reoperation after PTX+AT were enrolled in this study during the period from Aug 2012 to Dec 2021 in the Department of Otolaryngology Head and Neck Surgery of Peking University Civil Aviation School of Clinical Medicine, Civil Aviation General Hospital. The remaining parathyroid glands were located by preoperative colour Doppler ultrasonography, radionuclide imaging, enhanced CT and MR imaging in the neck region . Based on the imaging findings, the remaining parathyroid glands were removed in situ, and the missed ectopic or extra parathyroid glands were resected with an extended surgical scope according to the parathyroid dissection method. The surgical effect was evaluated by the changes of clinical symptoms, the dynamic change of serum intact paramyroidhomone（i-PTH） between preoperative and postoperative periods and the surgical complications. Results:All the 18 patients accepted successful operation. 30 parathyroid glands were resected confirmed by postoperative pathology, including 16 in situ and 14 ectopic glands（5 in superior mediastinum, 4 in thymus, 2 in posterior mediastinum ,2 in thyroid glands, 1 in carotid sheath）.Osteoarthropathy and skin itching were significantly relieved or even disappeared at 6 h after surgery. The levels of serum i-PTH, calcium and phosphorus reached the standards and muscle weakness was significantly improved 1 week after surgery. 16 patients presented hypocalcemia and returned to normal after supplement of calcium. Hoarseness due to temporary injury of laryngeal nerve was found in 6 cases. No serious complications or death occurred after the operation.There was no recurrence after 1 year follow-up. Conclusion:Reoperation is the first choice for SHPT patients complicated with persistent hyperparathyroidism. Multiple imaging examinations are used to locate the residual parathyroid, especially the ectopic gland. Expanded surgical scope is applied to resect all the residual parathyroid glands（ectopic, in situ and concealed parathyroid） according to the concept of dissection parathyroidectomy. The surgery is effective and safe. Patients'quality of life and long-term survival rate is improved.

ODP085 Denosumab Induced Severe Hypophosphatemia

Abstract Introduction Denosumab is a receptor activator of nuclear factor kappa-B (RANK) ligand inhibitor used for treatment of osteoporosis and bone metastases in patients with solid tumors. Denosumab induced hypophosphatemia has been reported in less than 1% of patients, and in most cases described as mild to moderate in severity. We present a case of severe hypophosphatemia after denosumab treatment for diffuse bone metastases due to prostate cancer. Case report A 78-year-old male patient with history of diffuse bone metastases due to prostate cancer, schizophrenia on treatment and intermittent alcohol use, presented to the hospital with suicidal ideation and worsening fatigue. Patient was found to have a phosphorus levels of &amp;lt;1. 0 mg/dL (2.5-4.6 mg/dL), corrected calcium of 8.2 mg/dL (8.4-10.5 mg/dl), vitamin D 25 OH of 36.34 ng/mL (30-100 ng/mL), magnesium of 2.3 mg/dL (1.7-2.5 mg/dL), parathyroid hormone (iPTH) level of 379 pg/mL (10-65pg/mL) and serum creatinine of 1.1 mg/dL (0.5-1.2 mg/dL). Urinary studies showed 24 hour urinary phosphate 1282 mg/24h (360-1600 mg/24h), urine creatinine 1570 mg/24h (500-2150 mg/24h). There was no evidence of acidosis, chronic kidney disease, preexisting osteomalacia or vitamin D deficiency. The patient had no recent alcohol consumption and his alcohol level was undetectable. After reviewing the outside medical records it was noted that the patient had received denosumab 120 mg, 11 days prior to the hospital admission, as part of the management of bone metastases due to prostate cancer. The patient's baseline phosphorus prior to denosumab was in the low normal range. The severe hypophosphatemia and secondary hyperparathyroidism were attributed to denosumab administration. Patient was initially treated with intravenous phosphate and then transitioned to oral phosphate along with elemental calcium and calcitriol during the course of his hospitalization. Patient's phosphorus improved to 2.3 mg/dL by the time of discharge. Discussion In patients treated with denosumab, the primary concern is potential post-treatment hypocalcemia, however, our case brings attention to severe hypophosphatemia as a serious side effect to treatment with denosumab. Multiple specialties are involved in the treatment of osteoporosis and metastatic bone lesions, and each should be aware that denosumab can lead to lower serum phosphate levels due to its effects on bone resorption and reduction of proximal tubular reabsorption of the phosphate resulting in clinical symptoms of muscle weakness, bone pain, fractures and even stupor, coma and death. We therefore conclude that monitoring phosphate levels should be part of the pre- and post-treatment evaluation in patients who are candidates for treatment with denosumab, particularly high-dose denosumab. Presentation: No date and time listed

Coronary artery calcification in patients with advanced chronic kidney disease

IntroductionCardiovascular disease (CVD) is associated with higher morbidity and mortality rates in patients with chronic kidney disease (CKD). Studies have shown that vascular calcification is a major predictor of CVD. Vascular calcification in the CKD population is associated with various risk factors, and changes in bone and mineral metabolism have been linked to an increased risk of atherosclerosis. Therefore, we aimed to investigate the correlation between vascular calcification and bone metabolism, which is necessary to improve the survival and prognosis of patients with CKD.MethodsWe included 146 patients with CKD who received coronary artery calcification (CAC) scores at our hospital from May 2017 to November 2018. Spearman rank correlation analysis, Mann–Whitney U test, and Kaplan–Meier method were used to analyze laboratory data and all-cause mortality.ResultsIn the 146 patients, chronic glomerulonephritis accounted for the most common cause of CKD, at approximately 39.0%. Spearman rank correlation analysis on the factors influencing vascular calcification in patients with CKD showed that CAC score was significantly and positively correlated with C-reactive protein, N-terminal/midregion osteocalcin (N-MID), N-terminal peptide of type 1 procollagen (P1NP), β-cross-linked C-telopeptide of type 1 collagen (β-CTx), and parathyroid hormone (P = 0.0423, P = 0.0432, P = 0.0235, P = 0.0061, P < 0.0001, respectively). Serum calcium levels were positively correlated with N-MID, P1NP, β-CTx, and iPTH (r = 0.19, r = 0.24, r = 0.21, r = 0.21, respectively), and serum phosphorus levels were positively correlated with N-MID, P1NP, β-CTx, and iPTH (r = 0.50, r = 0.37, r = 0.50, r = 0.55, respectively). However, no difference was found in CVC scores among patients with CKD in different stages and receiving different treatments. In the Kaplan–Meier analysis of all-cause hospitalization and mortality rates, patients with CAC > 400 had a higher risk.ConclusionWe found that the primary cause of CKD is glomerulonephritis, and the CAC score is positively correlated with inflammatory and bone metabolism markers, with a higher risk of all-cause mortality and cardiovascular hospitalization when the CAC score is greater than 400.

The current status of chronic kidney disease-mineral and bone disorder management in China

Chronic kidney disease-mineral and bone disorder (CKD-MBD) is one of the most common complications of patients with chronic kidney disease (CKD). After considering updated international and domestic CKD-MBD management guidelines, the current management status of CKD-MBD in China remains unclear. We aimed to investigate the management status of CKD-MBD in China. A nationwide survey was combined with a real-world study from Sichuan. Targets recommended in KDIGO 2017 and Chinese 2019 guidelines were used as targets. We compared the data between Sichuan from western China and the eastern developed areas of China, and also compared the results of the real-world data from Sichuan with those of DOPPS5. In the questionnaire, a total of 51,039 maintenance hemodialysis (MHD) patients from 272 centers were involved. Estimated achievement rates for Ca (2.1–2.5 mmol/L), P (1.13–1.78 mmol/L), and iPTH (150–600 pg/mL) levels were 57.1%, 41.1% and 52.0%, respectively. Differences in MBD management between Sichuan from questionnaire and central region. In the real-world survey, a total of 7,053 patients were enrolled. Among them, 57.6%, 24.3%, and 55.0% of patients met corrected Ca, serum P, and iPTH targets specified in Chinese 2019 guidelines, respectively. The comprehensive achievement rate was 7.5%. There are differences in MBD management between Sichuan and DOPPS5 regions, with Sichuan being relatively poorer. The level of the above parameters varies among different genders, age groups, and hospital grades. The achievement rate of serum P was higher in tertiary hospitals and elderly patients (P < 0.05). Current MBD management is poor. Phosphate levels in patients treated in secondary and lower hospitals and young dialysis patients should be strengthened.

Determinants of Low Bone Turnover in Type 2 Diabetes-the Role of PTH

Determinants of low bone turnover in type 2 diabetes (T2DM) are poorly understood. To investigate the relationship between markers of bone turnover, glycaemic control, disease duration and calciotropic hormones in T2DM we assessed baseline biochemical data from the DiabOS Study, a prospective multicenter observational cohort study. In a cross-sectional study-design data from 110 postmenopausal women and men aged 50–75 years diagnosed with T2DM for at least 3 years and 92 non-diabetic controls were evaluated. Biochemical markers of bone formation (N-terminal propeptide of type I procollagen [PINP]), bone-specific alkaline phosphatase [BAP]) and resorption (C-terminal cross-linking telopeptide of type I collagen [CTX]), measures of calcium homeostasis (intact parathormone [iPTH], 25-Hydroxyvitamin D, calcium, magnesium) and glycaemic control were assessed. After adjustment for age, gender and body mass index (BMI), patients with T2DM had lower serum levels of PINP (p < 0.001), CTX (p < 0.001), iPTH (p = 0.03) and magnesium (p < 0.001) compared to controls. Serum calcium, creatinine, 25-Hydroxyvitamin D and sclerostin did not differ between both groups. In multivariate linear regression analyses only serum iPTH remained an independent determinant of bone turnover markers in T2DM (PINP: p = 0.02; CTX: p < 0.001 and BAP: p < 0.01), whereas glycated haemoglobin (HbA1c), disease duration, age and BMI were not associated with bone turnover. In conclusion low bone turnover in T2DM is associated with low iPTH. The underlying mechanism remains to be elucidated.

Correlation between magnesium sulphate exposure in utero and serum calcium and alkaline phosphatase levels in preterm infants

Magnesium sulphate (MgSO4) is administered to pregnant women at risk of preterm labour and eclampsia. Since prolonged exposure to antenatal MgSO4 is considered to be a risk factor for infant skeletal demineralization, we evaluated infants exposed to antenatal MgSO4 for bone and mineral metabolism using their umbilical cord blood. The study population comprised 137 preterm infants. Forty-three infants were exposed (exposure group) and 94 infants were not exposed (control group) to antenatal MgSO4. Blood samples from the umbilical cords and infants were analysed with respect to mineral metabolism, intact parathyroid hormone (iPTH) level, and alkaline phosphatase (ALP) level. Correlation between the level of these parameters and the duration and dosage of MgSO4 was also examined. Preterm infants in the exposure group were antenatally exposed to MgSO4 for a median (IQR) period of 14 (5-34) days and a dosage of 447 (138-1118) g. Serum calcium levels were lower (8.8 vs 9.4 mg/dL, p<0.001) and ALP levels were higher (312 vs 196 U/L, p<0.001) in the exposure group. Serum calcium levels did not correlate with MgSO4 administration dosage and therapy duration, however, ALP levels correlated with the duration and total dosage of MgSO4 (Spearman's rank correlation r [95% confidence interval]: 0.55 [0.30-0.73], p <0.001 and 0.63 [0.40-0.78], p <0.001, respectively). Prolonged periods and higher doses of antenatal MgSO4 exposure can cause in utero abnormal bone metabolism in preterm infants.

Clinical expression of microRNA-144-5p and its regulatory effect on renal function in uremia.

The study commits to probing the clinical expression of microRNA-144-5p (miR-144-5p) and its modulatory effect on the renal function of uremia. Levels of blood urea nitrogen (BUN), β2-microglobulin (β2-MG), serum creatinine (Scr), blood calcium (Ca), phosphorus (P), and intact parathyroid hormone (iPTH) and miR-144-5p expression in serum of uremia patients were detected. The correlation among miR-144-5p expression with BUN, β2-MG, Scr, Ca, P, and iPTH levels in uremic patients was analyzed. The rats were injected with miR-144-5p agomir to detect the change of BUN, Scr, β2-MG, Scr, Ca, P, and iPTH levels in uremic rats. miR-144-5p expression in uremic patients was negatively correlated with BUN, Scr, β2-MG, P, and iPTH levels, and positively correlated with free Ca concentration in blood. miR-144-5p elevation reduced BUN, Scr, β2-MG, P, and iPTH levels, and increased free Ca concentration in blood in uremic rats. miR-144-5p is lowly expressed, and miR-144-5p has a regulatory effect on renal function in uremia.

Lower Bone Turnover and Skeletal PTH Responsiveness in Japanese Compared to European Patients on Hemodialysis.

Parathyroid hormone (PTH) treatment targets for patients receiving hemodialysis (HD) are lower in Japan than in Europe. Whether this translates to lower bone turnover is unknown and could depend on skeletal PTH responsiveness. This study investigates whether skeletal PTH responsiveness is better preserved in Japanese vs European patients receiving HD. This is a post hoc analysis of data from 2 prospective cohort studies, using a case-control design. Patients receiving chronic intermittent HD therapy were eligible for inclusion. Participating Belgian and Japanese patients (n = 374) were matched 1:1 by age (59 ± 12 years), sex (66% male), diabetes (34%), and dialysis duration (39 months [22-63 months]). PTH, bone-specific alkaline phosphatase (BALP), and tartrate-resistant acid phosphatase isoform 5b (TRAP5b) were measured centrally in Liège, Belgium. Japanese patients had lower levels of iPTH (207 vs 268 pg/mL; P < .001), BALP (15.3 vs 24.5 μg/L; P < .001), and TRAP5b (3.35 vs 5.79 U/L; P < .001). Linear regression analyses revealed lower levels of bone turnover markers for any given level of PTH in Japanese vs Belgian patients, indicating lower skeletal PTH responsiveness. Consistently, bone turnover markers were significantly lower in Japanese vs Belgian patients when stratifying or matching according to PTH levels. Male sex, obesity, and hyperphosphatemia were the main determinants of the bone turnover marker/PTH ratios. Japanese patients receiving HD have lower bone turnover than their European counterparts, even at similar PTH levels. The rationale for the current regional differences in PTH treatment targets remains obscure and deserves further attention.

RELATIONSHIP BETWEEN VISFATIN AND SOME BIOMARKERS OF BONE TURNOVER IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Chronic kidney disease (CKD) is a progressive disease that might result in an end stage renal disease (ESRD), raising cardiovascular morbidity and mortality. Life expectancy among patients with CKD could significantly be reduced as a result of an advanced atherosclerosis and followed by a premature death from cardiovascular disease (CVD). CVD is a condition of a subclinical systematic inflammation that involves cytokines produced by adipose tissue. Visfatin is an adipocytokine with potentially important effects on glucose metabolism and atherosclerosis. Therefore, it could be treated like a new marker of endothelial dysfunction (ED) in CKD patients. It has been suggested that visfatin levels could increase as CKD progresses, which could be due to either the chronic inflammation associated with CKD and/or the hypoxia resulting from tubular necrosis, anemia and reduced capillary blood flow. As CKD progresses, visfatin levels among these patients most often spell increased mortality caused by cardiovascular events. The current research has been conducted among a total of 80 subjects with CKD who were divided into two groups - pre-dialysis (30) and hemodialysis treatment (50) patients from the Nephrology and Dialysis Clinic at the UMHAT “Sveta Marina” Varna. Demographics indicators and levels of visfatin, iFGF-23 and iPTH were inevstigated.

Relationship between serum parathyroid hormone levels and abdominal aortic calcification in patients starting hemodialysis who have never taken calcium tablets, calcitriol, or vitamin D analogs

Background Vascular calcification (VC) and secondary hyperparathyroidism (SHPT) are important causes of the high incidence of cardiovascular events in chronic kidney disease (CKD) patients. The relationship between parathyroid hormone (PTH) and VC is very complex. The aim of this study was to determine the correlation between PTH levels and abdominal aortic calcification (AAC) in patients starting hemodialysis who had not received calcium tablets, calcium-containing phosphorus binders, calcitriol, or vitamin D analogs. Methods Seventy-one patients were included. Latero-lateral X-ray lumbar radiography, serum intact PTH (iPTH) levels, and predialysis biochemical parameters were obtained. The degree of AAC was evaluated according to the methods described previously by Kauppila et al. Results We found that there was a strong negative correlation between serum PTH and AAC (Spearman’s rho −0.76, p < 0.001). Receiver operating characteristic (ROC) curve analysis showed that low serum PTH level could predict the presence and extent of AAC (area under the curve values were 0.9013 [p < 0.0001] and 0.780 [p = 0.0041], respectively). Conclusions Our results indicate that serum PTH level is significantly negatively correlated with AAC within a certain concentration range in patients starting hemodialysis who had not received calcium tablets, calcium-containing phosphorus binders, calcitriol, or vitamin D analogs.

The mediating role of bariatric surgery in the metabolic relationship between parathyroid hormone and 25-hydroxyvitamin D.

An optimal and sufficient concentration of 25-hydroxyvitamin D (25(OH)D) has been suggested as the level required to maximally suppress intact parathyroid hormone (iPTH). We evaluated the role of surgery-induced weight loss in determining the threshold(s) of 25(OH)D required to suppress iPTH. This study was conducted in the framework of the Tehran Obesity Treatment Study (TOTS). We prospectively analyzed 687 patients with severe obesity who participated in the TOTS and underwent bariatric surgery from March 2013 to March 2019. The patients were followed for 1year after surgery. Anthropometric parameters and serum levels of iPTH, 25OHD, phosphorous, and calcium were measured. Nonlinear and piecewise linear regression was used to evaluate the relationship between 25(OH)D and iPTH and to determine the 25(OH)D-suppression point at which iPTH was maximally suppressed. Body mass index was 44.6kg/m2 at the baseline and decreased to 29.7kg/m2 1year after surgery (P < 0.05). Before the surgery, iPTH and 25(OH)D showed an exponential relationship; iPTH began to decrease rapidly at 25(OH)D concentration of 12ng/mL, reaching maximal suppression at 30ng/mL. However, the relationship between 25(OH)D and iPTH was non-exponential 1year after surgery. The piecewise linear regression model revealed the 25(OH)D concentration of 21ng/mL as the inflection point following surgery-induced weight loss. In patients with severe obesity, PTH was suppressed at a relatively lower concentration of 25(OH)D; this threshold increased following surgery-induced weight loss. These findings suggest a role for bariatric surgery in regulating 25(OH)D metabolism in patients with obesity.

The short test with hydrochlorothiazide in differential diagnosis between primary normocalcemic and secondary hyperparathyroidism for inpatient treatment

Differential diagnosis between the normocalcemic primary hyperparathyroidism (nPHPT) and secondary hyperparathyroidism (SHPT) due to hypercalciuria remains a challenge. The aim of this study was to investigate the capability of short test with hydrochlorothiazide for the differential diagnosis of nPHPT and SHPT. A retrospective study was conducted with the participation of 28 patients who underwent a functional test with thiazide diuretics during hospitalization in the Department of parathyroid glands pathology and mineral disorders of the Endocrinology Research Centre, Russia. Parameters of mineral metabolism were evaluated before and 3-5 days after taking hydrochlorothiazide 50 mg/day. According to baseline and dynamic biochemical evaluation patients were divided into 3 groups. Group 1 (n=21) included patients with confirmed PHPT, who reached hypercalcemia accompanying with an elevated level of iPTH (n=19) or an increased level of iPTH accompanying with normocalcemia (n=2). In group 1, baseline Caadj. was 2.48 mmol/l [2.47; 2.52], iPTH 107.5 pg/ml [86.8; 133.0], after short test - 2.63 mmol/l [2.59; 2.66] and 102.1 pg/ml [95,7; 124,1]. Group 2 included only one who was diagnosed with SHPT, a normal value of iPTH with concomitant normocalcemia was achieved after 4 days of hydrochlorothiazide therapy (baseline Caadj. 2.35 mmol/l, iPTH 74.5 pg/ml vs at 2.27 mmol/l and 50.7 pg/ml respectively). Patients with doubtful results of the test entered in group 3 (n=6), they did not achieve significant changes in the calcium and iPTH levels, so it was recommended to continue the test on an outpatient basis (baseline Caadj. 2.39 mmol/l [2.33;2.45], iPTH 97.0 pg/ml [83.1;117.0]); after short test - 2.47 mmol/l [2.42; 2.48] and 91.3 pg/ml [86.9; 124.0] respectively). Groups with PHPT and SHPT and doubtful results significantly differed from each other in Caadj (р=0.003, U-test, Bonferroni correction Р0=0.006), but not in iPTH, daily calciuria, eGFR, and phosphorus. There were no significant differences in the incidence of classical complications of PHPT. The diagnosis of PHPT was confirmed in 21/28 patients 3-5 days after taking hydrochlorothiazide 50 mg/day. The obtained results are significant for the differential diagnosis in hospitalized patients with an unspecified genesis of hyperparathyroidism.

Secondary hyperparathyroidism due to multiple parathyroid carcinomas in a patient with chronic hemodialysis: a case report

Parathyroid carcinoma (PC) in cases of secondary or tertiary hyperparathyroidism is relatively uncommon, and only a few case reports have described this entity. Although some papers have reported patients with one or two parathyroid malignancies, multiple PC–especially three or more–have been even more rarely reported. Herein, we report a case of secondary hyperparathyroidism due to multiple PCs in a chronic hemodialysis patient. A 54-year-old man with end-stage kidney disease was referred for hyperparathyroidism. He had been diagnosed with chronic kidney disease in 2001 and had begun hemodialysis in 2009. In laboratory tests, intact parathyroid hormone (iPTH) was markedly elevated to 1,144.1 pg/mL (normal range: 15.0–68.3 pg/mL) and serum calcium was mildly elevated to 10.56 mg/dL (normal range: 8.5–10.3 mg/dL). Ultrasonography showed hypoechoic nodules in the posterior part of both thyroid glands. All three nodules showed increased uptake on a 99mTc sestamibi scan. The patient underwent total parathyroidectomy with autotransplantation to the right forearm. Histopathology findings showed three PCs with capsular invasion and one parathyroid hyperplasia. In the immediate postoperative period, the iPTH level dropped from 1,446.8 to 82.4 pg/dL and, after 1 month, to 4.0 pg/dL. This patient needed oral calcium carbonate and active vitamin D to maintain appropriate serum calcium levels. Although multiple PCs are rare, they can cause secondary hyperparathyroidism. Therefore, clinicians should suspect multiple PCs when patients’ serum iPTH levels are exceptionally high. Additionally, since PCs could occur in multiple glands, autotransplantation of the parathyroid gland after parathyroidectomy should be done carefully.

Calcium Challenge to Confirm Secondary Hyperparathyroidism Caused by Decreased Calcium Intake

ObjectiveSecondary hyperparathyroidism commonly occurs in the setting of mid-to low-normal serum calcium levels, often in the setting of chronic kidney disease, phosphate loading, vitamin D deficiency, or insufficient calcium intake or absorption. In this article, we report 9 patients who had adequate kidney function (estimated glomerular filtration rate >60 mL/min/1.73 m2) and normal 25-hydroxy vitamin D level (≥30 ng/dL) and whose secondary hyperparathyroidism resolved after starting adequate oral calcium intake. MethodsOur retrospective case series included 8 women and 1 man; the mean age was 69.0 ± 12.2 years (mean ± standard deviation). The initial intact parathyroid hormone (iPTH) level was 80.6 ± 13.4 pg/mL (reference range [ref], 10-65 pg/mL), corrected serum calcium level was 9.2 ± 0.2 mg/dL (ref, 8.5-10.5 mg/dL), serum phosphate level was 3.6 ± 0.4 mg/dL (ref, 2.5-4.9 mg/dL), 25-hydroxy vitamin D level was 42.2 ± 10.5 mg/dL (ref, 20-50 ng/mL), and estimated glomerular filtration rate was 72.6 ± 14.4 mL/min/1.73 m2. Patients were treated clinically with oral calcium 600 mg twice a day. ResultsiPTH was retested after a mean duration of 17.6 ± 12.7 days of calcium supplementation; the iPTH level decreased to 51.0 ± 10.6 pg/mL, with all patients achieving iPTH in the normal range with normocalcemia, consistent with hyperparathyroidism being because of insufficient calcium intake or absorption. All patients were normocalcemic after supplementation. ConclusionSecondary hyperparathyroidism can result from insufficient oral calcium intake. Calcium challenge is an efficacious and cost-effective tool for confirming and treating secondary hyperparathyroidism in the setting of normal vitamin D levels and kidney function.

Intraoperative quantitative assessment of parathyroid blood flow during total thyroidectomy using indocyanine green fluorescence imaging - surgical strategies for preserving the function of parathyroid glands.

ObjectiveWe investigated the factors affecting postoperative parathyroid gland (PTG) function and devised an objective index to predict the postoperative PTG function during total thyroidectomy.MethodThis was a retrospective clinical review of 21 consecutive patients who were diagnosed with papillary thyroid carcinoma and underwent total thyroidectomy. The maximum intensity ratio (MIR) was determined as the maximum fluorescence intensity after ICG injection divided by the intensity before ICG injection.ResultsPostoperative hypoparathyroidism is significantly associated with simultaneous central neck dissection (CND) and lateral neck dissection (LND) (p = .032). The Spearman correlation test showed a moderate correlation between the MIR and iPTH levels (p = .0047). The optimal MIR cutoff value for predicting postoperative hypoparathyroidism was 2.14 with area under the curve = 0.904 (sensitivity: 0.769 and specificity: 1.00).ConclusionCND + LND was significantly associated with postoperative hypoparathyroidism. MIR was found useful in predicting the postoperative PTG function.Level of Evidence: 3b.

Effects of Normal Reference Range of Phosphorus and Corresponding PTH on Endothelial Function in CKD Patients.

IntroductionEndothelial dysfunction commonly occurs in chronic kidney disease (CKD) patients and increases the risk for cardiovascular disease. Among CKD patients, biomarkers involved in the pathogenesis of CKD-mineral bone disorder (CKD-MBD), such as phosphorus, parathyroid hormone, and fibroblast growth factor 23, are associated with endothelial dysfunction. We investigated whether these biomarkers induce endothelial dysfunction in CKD patients with normal phosphorus levels.MethodsThis cross-sectional study examined CKD patients with normal phosphorus levels; patients with an estimated glomerular filtration rate (eGFR) <15 or who were under dialysis were excluded. Iontophoresis with laser doppler flowmetry (ILDF) and peripheral arterial tonometry were performed to assess endothelial function in 85 patients. Pearson's correlation coefficient, multiple regression, and mediation analyses were performed to examine the association between CKD-MBD biomarkers and endothelial dysfunction.ResultsEndothelial dysfunction was observed in all subjects with a low response to ILDF and 27% of subjects according to peripheral arterial tonometry. Acetylcholine (Ach)-induced ILDF was significantly associated with eGFR (r = 0.22, P = 0.04), intact parathyroid hormone (iPTH; r = −0.46, P < 0.01), and VCAM-1 (r = −0.36, P < 0.01). The reactive hyperemia index (RHI) was significantly related to phosphorus levels (r = 0.32, P < 0.01) and iPTH (r = −0.39, P = 0.02). After adjusting for eGFR, iPTH and VCAM-1 remained independent factors for predicting endothelial dysfunction measured using Ach-induced ILDF. In addition, iPTH and phosphorus levels were independent predictors for endothelial dysfunction measured using RHI in the eGFR-adjusted model. Mediation analyses showed that the individual indirect effects of iPTH were significantly affected ILDF and RHI.ConclusionSerum levels of phosphorus and iPTH are associated with endothelial dysfunction, even in CKD patients with normal phosphorus levels.