Median Parathyroid Hormone Levels Research Articles

Correlation of Parathormone and Bone Disorders in Black Adult Hemodialysis Patients in the Public Sector in Abidjan, Côte d’Ivoire

Introduction: The progression of chronic kidney disease (CKD) is characterized by several complications, including disorders of phosphocalcium metabolism characterized by secondary hyperparathyroidism. For this reason, major international recommendations call for at least annual parathyroid hormone (PTH) determinations in patients suffering from CKD, particularly in the terminal phase. This study aims to explore parathyroid hormone status and bone disorders in adult hemodialysis patients in the public sector of Abidjan, West Africa. Materials and Methods: This was a cross-sectional study of 100 end-stage chronic renal failure patients treated by hemodialysis. Parathyroid hormone (PTH) was determined by ELFA enzyme-linked immunosorbent assay on the VIDAS® platform. PTH values were interpreted in relation to the range of 2 to 9 times the upper normal limit in healthy subjects, in line with current KDIGO recommendations, and compared with clinical bone complications. Results: Median PTH level was 315.95 (123.37-725.22) pg/mL. 48% of patients had PTH levels above the recommended threshold. Of these, almost half had no bone complications. Conclusion: The present study did not show a direct relationship between bone complications and the PTH thresholds recommended by KDIGO. This result allows us to envisage a possible inadequacy of the cut-off values for these black African dialysis patients, through subsequent studies.

MRNA expression of vitamin D receptor, calcium-sensing receptor, cyclin D1, and PTH in symptomatic and asymptomatic primary hyperparathyroidism.

The exact underlying mechanism for the differential clinical profiles of symptomatic and asymptomatic primary hyperparathyroidism (PHPT) patients has not been fully elucidated, and efforts to define the molecular mechanisms underlying the phenotypic heterogeneity of PHPT have been limited. The aim of this study was to explore the underlying molecular mechanisms involved in the pathogenesis of symptomatic and asymptomatic sporadic PHPT in Asian Indians. A prospective cohort study was conducted at a tertiary care hospital in North India. PHPT patients who underwent parathyroidectomy were included. The main outcome was the comparison of vitamin D receptor (VDR), calcium-sensing receptor (CaSR), cyclin D 1 (CD1), and parathyroid hormone (PTH) mRNA levels between symptomatic and asymptomatic PHPT patients and controls determined via quantitative real-time polymerase chain reaction (qRT-PCR). Forty-two PHPT patients were studied. The mean (SD) age was 49.7 (12.8) years. Twenty patients were asymptomatic. The median PTH levels were significantly greater in the symptomatic group than in the asymptomatic group (878 vs 653 pg/mL). CaSR and VDR mRNAs were significantly lower in both symptomatic and asymptomatic patients than in controls. CD1 and PTH mRNAs were significantly increased in symptomatic patients, but not in asymptomatic PHPT patients compared with controls. Symptomatic PHPT patients had significantly greater CD1 mRNA expression and reduced CaSR expression than asymptomatic patients. Symptomatic PHPT patients had significantly greater CD1 mRNA expression and lower CaSR expression than asymptomatic patients, underscoring the importance of the molecular mechanisms underlying the phenotypic heterogeneity of PHPT.

The role of anatomical and functional orientation in identification of parathyroid glands for patients with parathyroidectomy.

To investigate diagnostic approaches for preoperative localization of secondary hyperparathyroidism, as well as to give surgeons with precise parathyroid gland localization and imaging so that surgery can be performed safely. The clinical data of 710 patients with secondary hyperparathyroidism who underwent surgery in our center from October 2009 to October 2023 were retrospectively analyzed. The changes in calcium, phosphorus, and parathyroid hormone levels were observed to ascertain the anatomical location and number of parathyroid glands. Among the 710 patients, 55 underwent total parathyroidectomy, the others underwent total parathyroidectomy with autotransplantation. In total, 2,658 parathyroid glands were removed, with 43 glands being removed in 35 reoperation cases. The median parathyroid hormone level at 6 months postoperatively was 13.40 (interquartile range, 7.00-29.80) pg/mL. The detection rates of the parathyroid glands before first and repeat surgeries were higher using 99mTc-MIBI SPECT/CT fusion imaging than ultrasound (P<0.05). The sensitivity of combined preoperative 99mTc-MIBI SPECT/CT and ultrasound was 92.31%, higher than that of either 99mTc-MIBI SPECT/CT fusion imaging or ultrasound alone (P < 0.05). The incidence of ectopic parathyroid glands was 23.8%, and the incidence of ectopic left lower parathyroid glands was 13.2%. The left lower parathyroid gland was the most prone to ectopia. 99mTc-MIBI SPECT/CT fusion imaging, paired with high-frequency ultrasound, can be utilized to diagnose SHPT preoperatively. The most common ectopia site is the left lower parathyroid gland, which is located primarily in the thymus and superior mediastinum. Understanding the functional anatomical distribution of the parathyroid glands is critical for developing effective surgical methods for secondary hyperparathyroidism.

PTH may predict early mortality in incident patients on hemodialysis: results from a large cohort.

Parathyroid hormone (PTH) is merit as a risk factor for mortality in patients with chronic kidney disease in prevalent hemodialysis patients in a U shape. Most studies, however, do not focus on incident patients and those who died within the first 90days of therapy. We evaluated PTH as a risk factor for mortality in a large cohort population in Brazil. This is an observational cohort study that included 4317 adult patients who initiated hemodialysis between July 1st, 2012 and June 30, 2017. The main outcome was all-cause mortality. Fine-gray sub-distribution hazard models were used to evaluate survival in the presence of a competing event (kidney transplant). Median PTH levels of 252 (118, 479) pg/mL. There were 331 deaths during the first 90days of therapy (6.7%), 430 in a 1-year follow-up (10.7%) and 1282 (32%) during the 5-year study period. Deaths according to PTH < 150, 150-600 and > 600pg/mL corresponded to 38.1%, 33.0% and 28.5%, respectively (p < 0.001). In an adjusted model, patients who started dialysis with PTH < 150pg/mL had a higher mortality risk within the first 90days, but not in 1year and 5years after starting dialysis. Analyses in a subset of patients with a repeated PTH in 1year (N = 1954) showed that although persistent PTH low levels (< 150pg/mL) at 1year were significantly associated with all-cause mortality, this result was not sustained after multiple adjustments. PTH < 150pg/mL confers a high mortality risk in the first 90days of dialysis. If this result reflects poor nutritional conditions, it deserves further investigations.

Lower Parathyroid Hormone Levels are Associated With Reduced Fracture Risk in Japanese Patients on Hemodialysis

Secondary hyperparathyroidism (SHPT) affects bone metabolism and may lead to bone fragility. However, there is conflicting evidence as to whether parathyroid hormone (PTH) levels are associated with fracture risk and whether the relationship is linear or U-shaped. We examined the association between PTH levels and the risk of any fracture and site-specific fractures in a nationwide cohort of 180,333 patients on hemodialysis. We also examined the association between the percent change in PTH levels during the preceding 1 year and subsequent fracture. At baseline, the median intact PTH level was 141 pg/ml (interquartile range, 78-226 pg/ml). During 1 year of follow-up, there were a total of 3762 fractures requiring hospitalization (1361 hip, 551 vertebral, and 1850 other). In an adjusted analysis, higher baseline PTH levels were associated with an incrementally increased risk of any fracture (odds ratio [OR] per doubling of intact PTH, 1.06; 95% confidence interval, 1.03-1.09). The association between PTH levels and fracture risk was more pronounced for hip fractures but not found for vertebral fractures. The absolute risk difference associated with higher PTH levels appeared to be more pronounced in older individuals, females, and those with lower body mass index (BMI). Change in PTH levels was also associated with fracture risk: the adjusted OR for fracture decreased linearly with decreasing PTH levels over 1 year, regardless of the preceding PTH levels. Lower PTH levels are associated with a graded reduction in fracture risk. Further studies are needed to determine whether intensive PTH control reduces fracture risk.

The role of parathyroid autotransplantation for hypoparathyroidism following total thyroidectomy with bilateral central neck dissection.

Hypoparathyroidism is the most common complication for patients who undergo total thyroidectomy (TT) with bilateral central lymph node dissection (BCLND). The objective of this retrospective study was to investigate the relationship between parathyroid autotransplantation (PA) and postoperative hypoparathyroidism. Four hundred and sixty-five patients with papillary thyroid carcinoma (PTC) who underwent TT with BCLND (including prophylactic and therapeutic BCLND) by the same surgeon were enrolled in this retrospective study. They were divided into five groups based on the number of PAs. Group 0 was defined as no PA, while Group 1, 2, 3, and 4 were considered as 1, 2, 3, and 4 PAs during TT with BCLND, respectively. Transient and permanent hypoparathyroidism occurred in 83 (17.8%) and 2 (0.4%) patients who underwent TT and BCLND, respectively. The incidence of transient hypoparathyroidism increased gradually with an increase in the number of PAs. Compared with the previous group, Groups 2 and 3 had significantly more cases of transient hypoparathyroidism (p=0.03 and p=0.04, respectively). All cases of permanent hypoparathyroidism occurred in the patients without PA. Compared with Group 0, there were more removed central lymph nodes (RCLNs) in patients with one PA. Furthermore, Group 2 had more metastatic central lymph nodes(MCLNs) and RCLNs than Group 1.The number of PAs was the only identified risk factor for transient hypoparathyroidism after the multivariate logistic regression analysis. The median parathyroid hormone level recovered to the normal range within 1 month after surgery. With an increasing number of PAs, the possibility of transient hypoparathyroidism also increases in patients with PTC who undergo TT and BCLND. Considering the rapid recovery of transient hypoparathyroidism in 1 month, two PAs during TT and BCLND could be a good choice, leading to an increase in the central lymph node yield and no permanent hypoparathyroidism. However, this conclusion should be validated in future multicenter prospective studies.

#1286 Utility of cinacalcet treatment in kidney transplant recipients with persistent hyperparathyroidism

Abstract Background and Aims Secondary hyperparathyroidism occurs in the majority of patients with chronic kidney disease (CKD). It may persist in up to 50-66% of patients despite the initial decrease in PTH levels after successful kidney transplantation (KT). Maintaining parathyroid hormone (PTH) levels within the normal range during the post-transplant period is crucial because it is related to hypercalcemia, hypophosphatemia, and reduced bone mass in KT recipients. Studies have already demonstrated that persistent hyperparathyroidism is associated with graft loss and all-cause mortality. Vitamin D, vitamin D analogs, and calcimimetics are most commonly used to manage hyperparathyroidism. However, studies about the long-term effect of calcimimetic therapy on the allograft are still limited. In this study, we aim to investigate the long-term allograft results of patients who received cinacalcet treatment for hyperparathyroidism. Method This study was conducted in Gazi University nephrology dialysis and transplantation unit with 312 patients who were transplanted between 1996 and 2019 and continued routine follow-up visits. Persistent hyperparathyroidism is defined as elevated PTH levels after the first year of KT (serum PTH&amp;gt;88 pg/mL). All patients without concurrent hypercalcemia were treated with vitamin D or analogs according to their vitamin D levels. Patients with non-functional allograft and parathyroidectomy after KT were excluded from this study. In addition, patients with rejection episodes, which could be confounding factor for allograft survival, were excluded to evaluate the isolated effect of cinacalcet on the allograft function. We identified 115 patients with persistent hyperparathyroidism, of whom were treated with cinacalcet (n = 21) or not (n = 94). We analyzed the baseline characteristics, comorbidities, and immunosuppressive treatments of the groups. Additionally, annual eGFR changes (Δ eGFR) calculated based on baseline (post-transplantation 6th month) eGFR after KT was also examined to evaluate the effect of cinacalcet on the graft. Results The mean age of the patients was 44.3 ± 12.6 years, and 47 (41%) were women. The median follow-up time of the patients was 87 (49-117) months. Twenty-nine patients (25%) underwent cadaveric transplantation, and 47 (41%) patients received anti-thymoglobulin (ATG) in induction therapy. While all patients were given glucocorticoids as maintenance immunosuppressive therapy, 93 (81%) of the patients received tacrolimus and, 9 (8%) cyclosporin as CNI, 78 (68%) received anti-metabolite therapy. Fifty-eight patients (19%) were used mTORi. A total of 21 patients with persistent hyperparathyroidism (21%) were treated with cinacalcet. Dialysis time is longer in the cinacalcet-treated group than in the patients not treated with cinacalcet (p &amp;lt; 0.001). The preemptive transplantation rate was lower (p = 0.03), and the delayed graft function was higher in the cinacalcet-treated group (p = 0.04). In the first year after KT, serum median PTH levels were 227 (167-341) pg/ml in the cinacalcet group and 110 (86-160) pg/ml in the other group, respectively (&amp;lt;0.001). Also, serum phosphate level is lower in the treatment group (2.7 ± 0.4 mg/dl vs. 3.1 ± 0.7 mg/dl, p = 0.03). At the last visit of patients, we observed similar median PTH levels between groups [141 (100-222) vs. 108 (73-159), p = 0.08]. During the follow-up, CMV episodes and BKV nephropathy diagnosis rates were similar between the groups (Table 1). Δ eGFRs in the first year (p = 0.7), second year (p = 0.2), third year (p = 0.4), and fifth year (p = 0.6) after KT were similar between both groups. Conclusion Our study suggests that cinacalcet treatment could be a safe and effective treatment for patients with persistent hyperparathyroidism. In long-term follow-up, there is no evidence of a reduction of kidney function. However, more trials are still required for other clinical outcomes such as fracture risk and cardiovascular morbidity and mortality.

Pediatric Fractures: Does Vitamin D Play a Role?

Vitamin D (25-OHD) deficiency and insufficiency are reported in about half of all children. The literature on low 25-OHD and pediatric fracture risk presents inconsistent results. This study evaluates the association between pediatric fractures and 25-OHD, parathyroid hormone (PTH), and calcium. This is a prospective case-control study in 2 urban pediatric emergency departments (2014-2017). Patients aged 1 to 17 requiring intravenous access were enrolled. Demographics, nutrition, and activity information were recorded and levels of 25-OHD, calcium, and PTH were measured. Two hundred forty-five subjects were enrolled: 123 fractures and 122 controls. Overall, the mean 25-OHD level was 23ng/mL±8.5: 52 (21%) of patients were 25-OHD sufficient; 193 (79%) were not. Ninety-six percent of patients with lower extremity fractures had low 25-OHD versus 77% of patients with upper extremity fractures (P=0.024). The fracture cohort was younger (P=0.002), included more males (P=0.020), and spent more time playing outdoor sports (P=0.011) than the control cohort. The 25-OHD level (fracture 22.8ng/mL±7.6 vs. nonfracture 23.5ng/mL±9.3, P=0.494) and median calcium level (fracture 9.8mg/dL vs. nonfracture 10.0mg/dL, P=0.054) were similar between cohorts. The median PTH level was higher in the fracture than the control cohort (33 vs. 24.5pg/mL; P<0.0005); PTH was elevated to hyperparathyroidism (>65pg/mL) in 13% of fractures and 2% of controls (P=0.006). Matched subgroup analysis of 81 fracture patients and 81 controls by age, gender, and race showed that PTH was the only variable independently associated with increased odds of fracture (odds ratio=1.10, 95% CI, 1.01-1.19, P=0.021) in a model adjusted for vitamin D sufficiency and time spent playing outdoor sports. Low 25-OHD is common in children with fractures but we found no difference in 25-OHD levels between fracture and nonfracture cohorts. This research can impact evidence-based guidelines on vitamin D level screening and/or supplementation after fracture. Diagnostic level IV-case-control study.

#3579 AN INITIAL LOW-DOSE ETELCALCETIDE APPROACH IS EFFECTIVE AND COST-SAVING IN HEMODIALYSIS PATIENTS WITH MODERATE SECONDARY HYPERPARATHYROIDISM

Abstract Background and Aims Etelcalcetide (ETC) is an intravenous calcimimetic approved for the management of secondary hyperparathyroidism (sHPT) in hemodialysis (HD) patients, with benefits in terms of reduction of FGF23 levels and prevention of progression of left ventricular hypertrophy. The label recommendation is a starting dose of 5 mg after HD, to be titrated every 4 weeks according to parathyroid hormone (PTH) and calcium levels. However, it remains unclear what dosage is best to start with and, thus, how this treatment can be implemented in a real-life setting. The aim of this study was to assess the efficacy and cost-effectiveness of ETC started at lower doses than those suggested by the manufacturer in patients with moderate sHPT. Methods This is a retrospective observational study comparing two different initial ETC dosing strategies, a “Low-dose approach” (LD, ETC starting dose&amp;lt;10 mg/week) and a “Classic approach” (CL, ETC starting dose≥10 mg/week), in terms of effects on CKD-MBD related biomarkers and costs during the first year of prescription. The study was conducted on HD patients with basal PTH between 500 and 1500 ng/l, treated with ETC for at least 3 months between 2018 and 2022 at ASST Spedali Civili di Brescia. Monthly monitoring of serum calcium, phosphorus and PTH was performed in both groups for dose adjustment. Results Overall, 53 patients were identified, 24 in the LD and 29 in the CL group. Both groups showed similar baseline characteristics (Table 1). Median follow-up was 52 weeks, during which 4 patients (one in the LD and three in the CL group) discontinued ETC (Table 1). At the end of follow-up, 92% of patients in the LD and 90% in the CL group achieved a decrease in PTH ≥30% compared to baseline, with median PTH levels of 282 (207 - 332) and 294 (151 – 382) ng/l, respectively (p = 0.825). Other CKD-MBD biochemical parameters were comparable between the two groups at all timepoints (Figure 1). The median of average ETC weekly doses per patient was 7.6 (6.2 – 10.2) mg in the LD and 10.6 (9.7 – 15) mg in the CL group (p&amp;lt;0.001). During follow-up, the median ETC dose remained stable in the LD group, while partially decreasing in the CL group (Figure 1). Use of paricalcitol was comparable in both groups. At cost analysis, the median of average ETC weekly costs per patient was €36.6 (29.6 – 50.0) in the LD and €50.5 (46.4 – 71.7) in the CL group (p&amp;lt;0.001). This translates into an average yearly cost per patient of €1909 and €2635 using the LD and CL approach, respectively, with a saving of €726 per patient-year in favour of the LD strategy. Conclusion In this retrospective study in HD patients with moderate sHPT, we showed that starting ETC at a lower dose than the one suggested by the manufacturer is as effective as the classic approach in terms of control of CKD-MBD parameters, with a significant reduction in treatment costs. Future prospective studies will be needed to validate the results in bigger cohorts, test whether these benefits can extend beyond the first year of treatment and assess the effects on FGF23 levels and other relevant clinical outcomes.

Parathyroidectomy for Normocalcemic Tertiary Hyperparathyroidism: A 19-Year Experience.

Parathyroidectomy is the standard management for patients with tertiary hyperparathyroidism (THPT) and hypercalcemia. However, a subset of patients with THPT have normal or mildly-elevated serum calcium levels in the setting of significantly elevated parathyroid hormone (PTH). The purpose of this study is to determine the effectiveness and safety of parathyroidectomy in normocalcemic THPT. Retrospective review of 212 consecutive patients with THPT who subsequently underwent parathyroidectomy between 2001 and 2020 was performed. Patients were categorized as normocalcemic, "mild" (Ca ≤ 10.4mg/dL) or hypercalcemic, "classic" THPT (Ca ≥ 10.5mg/dL) and clinical data are compared. 71 of 212 (34%) were normocalcemic with median pre-operative Ca and PTH levels of 9.7mg/dL and 225pg/mL, respectively and 141 of 212 (67%) were hypercalcemic with median preoperative Ca and PTH levels of 11mg/dL and 211pg/mL, respectively. The mean length of stay was shorter in normocalcemic patients (0.33 versus 0.50d; P=0.03). 10 of 71 (14%) normocalcemic patients underwent reoperative parathyroidectomy, more than double that of hypercalcemic patients (5.6%; P=0.06). Concomitant thymectomy was performed in 28.1% and 22.1% of normocalcemia and hypercalcemic patients, respectively (P=0.44). No patient in either group required intravenous calcium or had undetectable PTH levels, but permanent hypocalcemia was more frequent in normocalcemic compared to hypercalcemic patients (11.2% versus 1.4%; P=0.03). Parathyroidectomy for normocalcemic tertiary hyperthyroidism (HPT) can be performed safely. These data can help guide multidisciplinary discussions for earlier surgical referral and intervention. Future investigations are needed to evaluate the impact of parathyroidectomy on the renal allograft, bone health, and cardiovascular disease.

Parathyroid hormone and phosphate homeostasis in patients with Bartter and Gitelman syndrome: an international cross-sectional study.

Small cohort studies have reported high parathyroid hormone (PTH) levels in patients with Bartter syndrome and lower serum phosphate levels have anecdotally been reported in patients with Gitelman syndrome. In this cross-sectional study, we assessed PTH and phosphate homeostasis in a large cohort of patients with salt-losing tubulopathies. Clinical and laboratory data of 589 patients with Bartter and Gitelman syndrome were provided by members of the European Rare Kidney Diseases Reference Network (ERKNet) and the European Society for Paediatric Nephrology (ESPN). A total of 285 patients with Bartter syndrome and 304 patients with Gitelman syndrome were included for analysis. Patients with Bartter syndrome type I and II had the highest median PTH level (7.5pmol/L) and 56% had hyperparathyroidism (PTH>7.0pmol/L).Serum calcium was slightly lower in Bartter syndrome type I and II patients with hyperparathyroidism (2.42versus 2.49mmol/L; P=.038) compared to those with normal PTH levels and correlated inversely with PTH (rs -0.253; P=.009). Serum phosphate and urinary phosphate excretion did not correlate with PTH. Overall, 22% of patients had low serum phosphate levels (phosphate-standard deviation score < -2), with the highest prevalence in patients with Bartter syndrome type III (32%). Serum phosphate correlated with tubular maximum reabsorption of phosphate/glomerular filtration rate (TmP/GFR) (rs 0.699; P <.001), suggesting renal phosphate wasting. Hyperparathyroidism is frequent in patients with Bartter syndrome type I and II. Low serum phosphate is observed in a significant number of patients with Bartter and Gitelman syndrome and appears associated with renal phosphate wasting.

Double water-clear cell parathyroid adenoma: a case report and literature review

Water-clear cell parathyroid adenoma is an uncommon cause of primary hyperparathyroidism. Herein, we report an interesting case of a 56-year-old man who presented with weight loss, bone pain, fatigue, and a palpable right neck mass. Laboratory tests indicated hypercalcemia, elevated parathyroid hormone (PTH) levels, and normal thyroid function. Further examinations detected osteoporosis and kidney stones. The ultrasound of neck revealed bilateral extrathyroidal tumors, which were sestamibi-avid. The patient underwent resection of the large right inferior and left inferior parathyroid tumors. Histopathology revealed a double water-clear cell parathyroid adenoma. His serum calcium and PTH levels normalized after surgery. The literature review identified 37 cases of water-clear cell parathyroid adenoma between 1985 and 2021. The median age at diagnosis was 56 years. Classic complications were common, including nephrolithiasis in nine and skeletal presentations in 10 patients. Before surgery, the median calcium and PTH levels were 12.0 mg/dL and 290 pg/mL, respectively. Overall, 89% were localized on ultrasonography, and 60% were positive on scintigraphy. Four patients had double adenomas. The median maximum diameter was 3.8 cm, and the median weight of the resected adenoma was 5.27 g. In summary, water-clear cell parathyroid adenoma has certain unique features. These include larger tumor size, relatively indolent biochemical profile, high prevalence of complications and nonspecific symptoms, an isoechoic appearance on ultrasonography, and reduced scintigraphic sensitivity.

Serum biotin interference: A troublemaker in hormone immunoassays

ObjectivesBiotin therapy can affect the results of many immunoassay procedures. The present study investigates biotin’s interference on 25-hydroxy vitamin D (25-OHD), parathyroidhormone (PTH) and thyroid-stimulating hormone (TSH) tests using four different assay systems and biotin neutralization. Design and methodsEnrolled in the study were 50 children diagnosed with biotinidase deficiency (BTD) undergoing treatment with biotin (5–20 mg/day) who were subjected to a series of analyses involving 25-OHD (Roche Diagnostics assays, Beckman Coulter assays, HPLC, LC/MS-MS), TSH, PTH (Roche Diagnostics assays, Beckman Coulter assays) and biotin (LC/MS-MS), before and after biotin neutralization with Streptavidin-coated magnetic particles (SMP). ResultsThe median biotin concentration was found to be 175.2 [94.0–307.1] μg/L. There was no significant difference in the 25-OHD results before and after neutralization with the Beckman Coulter, HPLC and LC-MS/MS assays. In contrast, the median 25-OHD level was seen to decrease from 90.2 [35.9–105.3] ng/mL to 29.1 [22.6–37.6] ng/mL after neutralization with the Roche assay (p < 0.0001). While there was no statistically significant difference in the values recorded before and after neutralization in PTH analysis using Beckman assay, the median PTH levels increased from 7.8 [1.6–21.6] pg/mL to 28.2 [22.5–41.9] pg/mL after neutralization with the Roche assay (p < 0.0001). The cut-off values at which serum biotin interfered in the Roche assay PTH test, with 25-OHD levels determined as 51.4 μg/L and 62.9 μg/L, respectively. A significant increase was detected in the TSH levels analyzed with a Roche assay after neutralization (from 2.36 [1.85–3.00] mIU/L to 2.74 [1.93–3.70] mIU/L, p < 0.0001). ConclusionsThe PTH, 25-OHD and TSH results were found to be affected by high biotin concentrations in Roche assays, leading to a risk of misdiagnosis, although SMP neutralization can suppress any such interference efficiently.

Elderly patients with hip fracture and subnormal renal function have inadequate response to vitamin D supplementation

IntroductionAll Danish citizens aged >70 years are recommended to take vitamin D supplements. We hypothesized that renal insufficiency may impair the activation and effect of vitamin D supplements. We aimed to investigate the association between use of vitamin D supplements, and levels of 25-hydroxy-vitamin D and parathyroid hormone (PTH) in elderly patients according to estimated glomerular filtration rate (eGFR). MethodsThe study was a sub-analysis of 164 patients with 25-hydroxy-vitamin D levels measured in a cross-sectional study of 200 consecutive patients aged ≥65 years admitted to hospital with hip fracture. ResultsVitamin D supplement-users (n = 68) had significantly higher 25-hydroxy-vitamin D levels regardless of eGFR ≤ or>60 ml/min. In patients with eGFR>60 ml/min (n = 103), median PTH levels were significantly lower in vitamin D supplement-users compared to non-users (4.8 [4.2–6.7] vs 6.25 [4.9–8.3] pmol/l, P = 0.039), while there was no difference in patients with eGFR≤60 ml/min (9.5 [5.4–16.7] vs 9.8 [5.9–16.9] pmol/l, P = 0.66 (n = 61)). ConclusionsUse of vitamin D supplements was associated with increased levels of 25-hydroxy-vitamin D, but only associated with decreased levels of PTH in patients with eGFR>60 ml/min. Thus, renal function may be essential to gain effect of vitamin D supplements, and 25-hydroxy-vitamin D levels may not reflect active Vitamin D status in elderly vitamin D supplement-users with hip fracture and decreased renal function. In addition to current guidelines for prescription of vitamin D supplements, it may be considered to monitor PTH or active vitamin D in elderly patients with eGFR<60 ml/min and adjust dose accordingly.

A Retrospective Study of Ultrasonography in the Investigation of Primary Hyperparathyroidism: A New Perspective for Ultrasound Echogenicity Features of Parathyroid Nodules

ObjectiveTo identify and understand parathyroid lesions of patients with primary hyperparathyroidism (PHPT) more accurately under ultrasound. MethodsThis retrospective study involved 423 adult patients with PHPT with a single parathyroid nodule and positive parathyroid ultrasonography between 2018 and 2019. The clinical characteristics of the study patients and histopathologic sections were reviewed. ResultsAccording to the main grayscale echogenicity features of parathyroid nodules, 423 cases were divided into groups: iso-hyperechogenicity solid (61/423), hypoechogenicity solid (304/423), and mixed-echogenicity cyst-solid (58/423) groups. Comparison among the 3 groups showed that the iso-hyperechogenicity group included more asymptomatic patients with PHPT and fewer patients with severe symptoms like bone fractures (P < .05). The mixed-echogenicity group showed higher median serum parathyroid hormone (PTH) and serum calcium levels and larger lesion sizes (P < .05), and the iso-hyperechogenicity group showed the lowest median serum PTH level. No difference in lesion size was noted between the 2 solid groups, but the median serum PTH level in the hypoechogenicity group was higher than that in the iso-hyperechogenicity group (P < .05). According to histopathology, the hypoechogenic area of the samples may contain more functional components (chief cells), whereas the iso-hyperechogenic area has more nonfunctional components (eg, lipocytes and connective tissues). ConclusionThe PHPT nodules distinguished by ultrasound echogenicity features showed different histopathologic components, reflected by different clinical characteristics of the patients with PHPT.

Prevalence of vitamin D deficiency and persistent hyperparathyroidism in an Egyptian cohort of renal transplant recipients

Background Vitamin D metabolism might be influenced by impaired allograft function and by persistently elevated parathyroid hormone (PTH) and fibroblast growth factor 23 levels as well. Hyperparathyroidism is a frequent and sometimes severe complication following renal transplantation. Purpose The primary objective was to measure the prevalence of vitamin D deficiency in renal transplant recipients in a single center (Almowasah Hospital). The secondary objective was to determine predictors of low 25-hydroxyvitamin D levels using patient characteristics to identify patients at a higher risk of vitamin D deficiency. Patients and methods A retrospective cross-sectional study was conducted on 55 renal transplant recipients for whom 25-hydroxyvitamin D was measured. Intact PTH was measured as well and compared with pretransplant values. Results The majority of the patients, representing ∼81.8%, were vitamin D deficient, whereas 14.5% had insufficient serum vitamin D level. A minority of the patients (3.6%) showed sufficient vitamin D level. The mean vitamin D level was 15.13±7.03 ng/ml. Approximately 38.2% of the patients showed evidence of persistent hyperparathyroidism. The median PTH level was higher in the pretransplant period, with a value of 308.0 pg/ml, compared with the posttransplant period (121.0 pg/ml). The difference was statistically significant (P&lt;0.001). Serum PTH level showed a reduction in its level by ∼55.79% after transplantation. Conclusion Vitamin D deficiency is highly prevalent in renal transplant recipients. It is also more prevalent in early than late transplant recipients, and there is a statistically significant inverse correlation between vitamin D and PTH.

Acute and long-term kidney function after parathyroidectomy for primary hyperparathyroidism.

In kidney transplant patients, parathyroidectomy is associated with an acute decrease in renal function. Acute and chronic effects of parathyroidectomy on renal function have not been extensively studied in primary hyperparathyroidism (PHPT). This retrospective cohort study included 494 patients undergoing parathyroidectomy for PHPT. Acute renal changes were evaluated daily until day 4 post-parathyroidectomy and were stratified according to acute kidney injury (AKI) criteria. Biochemical assessment included serum creatinine, total and ionized calcium, parathyroid hormone (PTH), and 25-hydroxyvitamin D (25OHD). The estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI equation. We compared preoperative and postoperative renal function up to 5 years of follow-up. A total of 391 (79.1%) patients were female, and 422 (85.4%) were non-African American. The median age was 58 years old. The median (first and third quartiles) preoperative serum creatinine, PTH and total calcium levels were 0.81 mg/dL (0.68-1.01), 154.5 pg/mL (106-238.5), and 10.9 mg/dL (10.3-11.5), respectively. The median (first and third quartiles) preoperative eGFR was 86 mL/min/1.73 m2 (65-101.3). After surgery, the median acute decrease in the eGFR was 21 mL/min/1.73 m2 (p<0.0001). Acutely, 41.1% of patients developed stage 1 AKI, 5.9% developed stage 2 AKI, and 1.8% developed stage 3 AKI. The acute eGFR decrease (%) was correlated with age and PTH, calcium and preoperative creatinine levels in univariate analysis. Multivariate analysis showed that the acute change was related to age and preoperative values of ionized calcium, phosphorus and creatinine. The change at 12 months was related to sex, preoperative creatinine and 25OHD. Permanent reduction in the eGFR occurred in 60.7% of patients after an acute episode. There was significant acute impairment in renal function after parathyroidectomy for PHPT, and almost half of the patients met the criteria for AKI. Significant eGFR recovery was observed during the first month after surgery, but a small permanent reduction may occur. Patients treated for PHPT seemed to present with prominent renal dysfunction compared to patients who underwent thyroidectomy.

Prevalence and risk factors of post-kidney transplant hyperparathyroidism: a single-center study

Objective:to assess the prevalence of hyperparathyroidism (HPT) and the factors affecting its development in kidney transplant recipients.Materials and methods. The single-center observational cohort study included 97 kidney transplant recipients – 40 men, 57 women, age 50 ± 9 years. Inclusion criteria: more than 12 months of post-transplant period, 3 months of stable renal transplant function. Non-inclusion criterion: therapy with vitamin D, with its alternatives or with cinacalcet. Dialysis ranged from 0 to 132 months (median 18); 46% of patients had pre-operative secondary HPT. A comprehensive laboratory study included evaluation of serum concentrations of parathyroid hormone (PTH), 25-OH vitamin D, calcium, phosphorus, magnesium, total alkaline phosphatase (ALP) activity, albumin, creatinine and daily proteinuria. At the dialysis stage, the target PTH range of 130–585 pg/ ml was used, in the post-transplant period – ≤130 pg/ml. Glomerular filtration rate (eGFR) was calculated using the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula.Results.Patients were divided into two groups based on PTH threshold level (130 pg/ml): the first with HPT (PTH &gt;130 pg/ml, median 203), the second without HPT (PTH ≤130 pg/ml, median 101). Both groups were comparable in terms of gender, age, primary renal disease, dialysis modality, post-transplant follow-up, and immunosuppressive therapy regimen. In group 1 and group 2 recipients, dialysis therapy, pre-transplant median PTH level, incidence of reoperation and incidence of immediate renal graft function were 30 (14; 50) and 14 (6; 28) months (p = 0.004), 681 (538; 858) and 310 (182; 556) pg/ml (p &lt; 0.001), 17% and 2% (p = 0.028), 51% and 80% (p = 0.005), respectively. At the time of the study, 72% of group 1 recipients had eGFR &lt;60 ml/min, versus 36% of group 2 (p &gt;&lt; 0.001). Among HPT biochemical parameters, there were differences for ionized serum calcium (1.32 ± 0.07 versus 1.29 ± 0.04 mmol/l, p = 0.017) and ALP activity (113 ± 61 versus 75 ± 19 u/l, p = 0.021). Serum vitamin D in both groups reduced in equal measures – 14 ± 4 and 15 ± 6 ng/ml.Conclusion.Persistent HPT in the long-term post-transplant period reaches 48.5%. Risk factors for its development included dialysis for more than 18 months, pre-operative secondary HPT, repeated kidney transplantation, delayed graft function, and eGFR &lt;60 ml/min.

SAT-387 Testing for Parathyroid Hormone: Performances of a Novel Fully Chemiluminescent Automated Assay

Background: Parathyroid hormone (PTH) is one of the key regulators of the bone and mineral metabolism. Testing for PTH is essential for the management of hyper- or hypo calcemia. Measurement of PTH is also an important tool for the monitoring of patient with chronic kidney diseases. Our study objective was to determine the performances of a novel fully automated chemiluminescent assay for testing of intact PTH. Methods: We evaluated the Maglumi® (Snibe) PTH assay a fully automated two-sites immunoluminometric method based on a solid-phase, paramagnetic microbeads, coated with a monoclonal antibody targeting PTH epitopes. Assay imprecision was assessed with two levels of control materials. Reference values were determined with samples of 24 healthy volunteers. Method comparison was performed with an electrochemiluminescent immunoassay (ECLIA) (Roche diagnostics) with 24 patients’ samples. Results: The between-run coefficients of variation of the Maglumi® PTH assay were 5.1 and 3.7 % for concentrations of 33 and 992 pg/mL, respectively. The median PTH levels were 121 pg/mL (range: 18 - 369) with the Maglumi assay and 117 pg/mL with the ECLIA method (range: 10 - 482). The upper limit of the reference interval in the healthy volunteers was 63 pg/mL. The correlation between the both methods was good (r=0.87, p<0,001). Passing-Bablok regression analysis showed a slope of 0.96 (95% confidence interval (CI): 0.83 to 1.35) and an intercept of -2.14 (95% CI: -20.49 to -10.47). Bland-Altman plot evidenced a bias between the methods with a mean bias of 4.6 pg/mL. Conclusions: Our preliminary data showed excellent concordance and analytical performances for the PTH fully automated immunoassay associated to perspectives of automation and reduction of turn-around time of analysis.

Perioperative Nursing of Patients with Reoperation of Recurrent Parathyroid Carcinoma Invading the Upper Digestive or Respiratory Tract.

Objective The aim of this study was to summarize the perioperative nursing care of patients with recurrent parathyroid carcinoma. Methods A retrospective analysis of 10 patients with recurrent parathyroid carcinoma was performed. The clinical data, diagnosis, treatment process, and nursing process (including clinical nursing intervention of various complications) were analyzed. The nursing experience and methods were discussed, summarized, and analyzed. Results A total of 10 patients were reviewed (male : female 7 : 3; aged 48.6 ± 14.60 years). The mean interval between the initial operation and reoperation was 2.23 ± 1.65 years. The mean number of operations was 4.00 ± 1.41. Invasion of the trachea or esophagus was evident in 7 patients, larynx in 6 patients, recurrent laryngeal nerve in 1 patient, and cyclic cartilage in 2 patients. Serum calcium range was 3.20–4.68 mmol/L, and parathyroid hormone (PTH) range was 860–2830 pg/ml at admission. 6 patients underwent prophylactic tracheostomy, 2 patients underwent partial laryngectomy, and 2 patients underwent total laryngectomy. 1 patient experienced temporary water-electrolyte disorder and hypoproteinemia. The median serum calcium was 2.28 mmol/L (1.66–3.18 mmol/L) and median PTH level was 82.60 pg/ml (63.70–900.00 pg/ml) postoperatively. Serum PTH and calcium were still higher than the upper limit of normal in 2 patients after surgery. 2 of the other 8 patients relapsed within 8–11 months, and 6 patients remained normal for 11–40 months. Conclusion For patients with reoperation of recurrent parathyroid carcinoma, high-quality, reasonable, and careful perioperative nursing ensured a successful operation and optimized outcome.