Achievement of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative: recommended serum calcium, phosphate and parathyroid hormone values with parathyroidectomy in patients with secondary hyperparathyroidism

Single-Center Experience of Parathyroidectomy Using Intraoperative Parathyroid Hormone Monitoring

Background and Objectives: Hyperparathyroidism (HPT) is a rare endocrine disease associated with the elevated metabolism of calcium, vitamin D, and phosphate by the hyperfunctioning of the parathyroid glands. Here, we report our experience of parathyroidectomy using intraoperative parathyroid hormone (IOPTH) monitoring in a single tertiary hospital. Materials and Methods: From October 2018 to January 2022, a total of 47 patients underwent parathyroidectomy for HPT. We classified the patients into two groups—primary HPT (PHPT, n = 37) and renal HPT (RHPT, n = 10)—and then reviewed the patients’ data, including their general characteristics, laboratory results, and perioperative complications. Results: Thirty-five of the thirty-seven patients in the PHPT group underwent focused parathyroidectomy, while all ten patients in the RHPT group underwent subtotal parathyroidectomy. IOPTH monitoring based on the Milan criteria was used in all cases. Preoperative and 2-week, 6-month, and 12-month postoperative parathyroid hormone (PTH) levels were within the normal range in the PHPT group, whereas they were higher than normal in the RHPT group. Transient hypocalcemia occurred only in the RHPT group, with calcium levels returning to normal levels 12 months after surgery. Conclusions: Parathyroidectomy with IOPTH monitoring in our hospital showed favorable clinical outcomes. However, owing to the small number of patients due to the low frequency of parathyroid disease, long-term, prospective studies are needed in the future.

Risk factors for hypocalcemia in dialysis patients with refractory secondary hyperparathyroidism after parathyroidectomy: a meta-analysis

Objective

Hypocalcemia after parathyroidectomy (PTX) results in tetany, diarrhea, cardiac arrhythmia, and even sudden death. However, a meta-analysis or systematic evaluation of risk factors with the occurrence and development of hypocalcemia in patients with secondary hyperparathyroidism (SHPT) after PTX has never been performed.

Methods

A thorough search of electronic databases, including PubMed, Web of Science, the Cochrane Library, and EMBASE, was performed to retrieve relevant studies from database inception to June 2021. Quality of the included studies was assessed by two independent reviewers using the Newcastle–Ottawa Scale. Review Manager 5.3 and Stata 16.0 were used for meta-analysis. The random-effects model was adopted to calculate the 95% CIs (I²> 50% or p < 0.05) of the combined effect size and the corresponding homogeneous data. Otherwise, a fixed-effects model was used.

Results

Thirteen studies including 2990 participants who met the inclusion criteria were enrolled in the present meta-analysis. The overall quality of the enrolled studies had a score of >7 points. Risk factors significantly related to hypocalcemia in patients with SHPT after PTX were preoperative serum calcium (OR 0.19, 95%CI 0.11–0.31), preoperative alkaline phosphatase (ALP) (OR 1.01, 95% CI 1.01–1.02), and preoperative intact parathyroid hormone (iPTH) (OR 1.38, 95%CI 1.20–1.58). Meanwhile, age (OR 0.97, 95%CI 0.87–1.10) was not significantly correlated with hypocalcemia after PTX.

Conclusions

Based on the current evidence, preoperative serum calcium, preoperative ALP, and preoperative iPTH were significant predictors of hypocalcemia in patients with SHPT after PTX. More attention should be given to patients with these risk factors for the prevention of postoperative hypocalcemia.

[Risk factors affecting graft survival after parathyroidectomy and parathyroid autotransplantation in patients on maintenance hemodialysis]

OBJECTIVE

To investigate the risk factors affecting the survival of parathyroid autograft following total parathyroidectomy combined with autologous sternocleidomastoid muscle transplantation (TPTX + AT) in patients on maintenance hemodialysis (MHD) complicated with secondary hyperparathyroidism (SHPT).

OBJECTIVE

This retrospective study was conducted among the patients on maintenance hemodialysis with SHPT, who underwent successful parathyroidectomy and autotransplantation from January, 2010 to February, 2020 in our hospital. The clinical data and serum levels of calcium, phosphorus, intact parathyroid hormone, hemoglobin, and alkaline phosphatase (ALP) of the patients were collected. The enrolled patients were divided into survival group with bilateral forearm parathyroid hormone (iPTH) ratio > 1.5 and death group with a ratio < 1.5 at 2 weeks after surgery for comparison of the clinical data and perioperative indicators. The risk factors of postoperative parathyroid autograft survival were analyzed using logistic regression analysis.

OBJECTIVE

A total of 87 patients were included in the study, among whom the graft survival rate after parathyroid transplantation was 78.16%. In both groups, serum levels of calcium, phosphorus, iPTH and ALP decreased and hemoglobin level increased significantly at 1 week and 1, 2, 3, 6 and 12 months after surgery (P < 0.01). Logistic regression analysis showed that serum ALP level was an independent risk factor for graft survival following parathyroid autotransplantation [OR=1.003, 95% CI: 1.001-1.005, P=0.004].

OBJECTIVE

TPTX+AT is a safe and effective treatment for SHPT, and parathyroid autografts are less likely to survive following parathyroid transplantation in patients with high preoperative level of ALP.

Predictors of early postoperative hypocalcemia after total parathyroidectomy in renal hyperparathyroidism

Purpose

Patients with secondary hyperparathyroidism are at high risk for developing postoperative hypocalcemia. However, there are limited data regarding predictors of postoperative hypocalcemia in renal failure patient with secondary hyperparathyroidism. This study aimed to determine the clinical presentations of renal hyperparathyroidism and the predictors of early postoperative hypocalcemia after total parathyroidectomy.

Methods

Data of patients with renal hyperparathyroidism who underwent total parathyroidectomy between January 2007 to December 2014 were reviewed retrospectively. Patients were divided into 2 cohort groups according to their serum calcium levels within 24 hours of parathyroidectomy: the hypocalcemia group (calcium levels of 2 mmol/L or less), and the normocalcemia group (calcium levels more than 2 mmol/L). With the use of multivariable logistic regression analyses, the predictors of early postoperative hypocalcemia after total parathyroidectomy in patients with renal hyperparathyroidism were investigated.

Results

Among 68 patients, 56 patients (82.4%) were symptomatic preoperatively. Fifty patients (73.5%) presented with bone pain and 14 patients (20.6%) had muscle weakness. Early postoperative hypocalcemia occurred in 25 patients (36.8%). Preoperative alkaline phosphatase level was the predictor of early postoperative hypocalcemia (adjusted odds ratio, 1.004; 95% confidence interval, 1.001–1.006; P = 0.002).

Conclusion

Results from our study show that most of the patients with renal hyperparathyroidism were symptomatic preoperatively and the most common clinical presentations were bone pain and muscle weakness. The significant predictor of early postoperative hypocalcemia after total parathyroidectomy was the preoperative alkaline phosphatase levels.

Clinical outcomes of parathyroidectomy versus cinacalcet in the clinical management of secondary hyperparathyroidism

Parathyroidectomy (PTX) is the standard treatment for secondary hyperparathyroidism (SHPT); however, the administration of cinacalcet has gained prominence as a noninvasive treatment. We aimed to determine whether PTX or cinacalcet is more effective in preventing morbidity and mortality through reviewing follow-up data concerning surgical management of SHPT. We retrospectively analyzed and divided 209 patients with SHPT into two treatment groups: PTX (n = 78) and cinacalcet (n = 131) groups. We compared clinical features, the over-the-target range rate during pre- and post-intervention periods, new cardiovascular events, and all-cause mortality between both groups. Almost all biochemical parameters were well controlled in the post-intervention period, and were within the recommended target range for the PTX group but not for the cinacalcet group. A significant difference was observed in the over-the-target range rate during the post-intervention period between the groups. PTX and cinacalcet interventions significantly lowered the over-the-target range rates for serum intact parathyroid hormone (iPTH) (>300 pg/mL), corrected calcium (>10.5 mg/mL), serum phosphorus (>5.5 mg/dL), and calcium-phosphorus product (>55) in both groups (p = 0.001). PTX reduced the risk of new cardiovascular events by 86% compared to cinacalcet (p = 0.001); however, all-cause mortality did not differ significantly (14.1% vs. 7.6%, p = 0.132). For patients with SHPT, PTX helps prevent cardiovascular events through normalizing biochemical variables, according to recommended guidelines. PTX should be considered before cinacalcet treatment to prevent new cardiovascular events. Early PTX for appropriate patients can help prevent immediate postoperative complications and mortality.

Nicotinic acid and related compounds: A meta-analysis of their use for hyperphosphatemia in dialysis patients

BACKGROUND

Studies indicate that nicotinic acid and related compounds may decrease phosphorus concentrations effectively by reducing the absorption in the gastrointestinal tract. However, the efficacy and safety of oral niacin treatments have only been investigated in a limited number of small-scale studies.

METHODS

We performed this meta-analysis by pooling 12 qualified relevant preclinical and clinical trials to evaluate the association of nicotinic acid (and its related compounds) treatment and hyperphosphatemia among dialysis patients. Baseline and after treatment data were collected from the studies to evaluate drug efficacy, effect on lipid profile, and drug safety. To evaluate drug efficacy, subgroups were created based on different exposure time (i.e., 4 wks, 8 wks, 12 wks, and 24 wks) and each subgroup was compared against baseline data. In the assessment of lipid profile and drug safety, results of 8-week treatment were compared against baseline data.

RESULTS

Our study showed that in the efficacy assessment of drug treatment, serum phosphorus concentration was only significantly reduced in the 4-week (SMD, 0.68; 95% CI, 0.40 to 0.97; P = .000; n = 8), and 8-week (SMD, 1.05; 95% CI, 0.68 to 1.42; P = .000; n = 10) treatment groups. The calcium × phosphorus product showed significantly reduced concentration in all the drug exposure time settings, and no rebound was detected (4-wk treatment: SMD, 0.61; 95% CI, 0.18 to 1.04; P = .005; n = 5; 8-wk treatment: SMD, 0.76; 95% CI, 0.32 to 1.18, P = .001; n = 8; and 12-wks treatment: SMD, 0.28, 95% CI, -0.06 to 0.61; P = .103; n = 3). Lipid profile monitoring showed that high-density lipoprotein (HDL) and triglycerides (TG) significantly changed after 8 weeks of treatment (HDL: SMD, -0.63; 95% CI, -1.03 to 0.24; P = .002; n = 5) and TG: SMD, 0.25; 95% CI, 0.02 to 0.49; P = .033; n = 5). Assessment of drug safety detected significant association for incidence of diarrhea (8% incidence rate; 95% CI, 4% to 12%; P = .001) and total adverse event (41% incidence rate, 95% CI: 12% to 69%, P = .001).

CONCLUSION

Our study concludes that nicotinic acid and related compounds can significantly reduce serum phosphorus concentration with additive antilipemic effects. We also recommend that the safety of this drug be further studied, as our results suggest significant incidence of adverse events.