Short- and long-term impact of subtotal parathyroidectomy on the achievement of bone and mineral parameters recommended by clinical practice guidelines in dialysis patients: a 12-year single-center experience

[Evolution of the incidence and results at 12 months of parathyroidectomy: 40 years of experience in a dialysis center with two successive surgical departments]

INTRODUCTION

Secondary hyperparathyroidism remains the main complication of mineral and bone metabolism in patients with chronic kidney disease. In case of resistance to medical treatment (native and active vitamin D, calcium and calcimimetics), surgical parathyroidectomy is indicated. The aim of this retrospective study is to show the evolution of the incidence and results of surgical parathyroidectomy in our center between 1980 and 2020 as patient characteristics, diagnostic and therapeutic strategies have changed.

PATIENTS AND METHODS

We collected data from dialysis patients who had a first surgical parathyroidectomy between 2000 and 2020 (period 2) in the same surgical department and compared them with historical data between 1980 and 1999 (period 1) operated in one other center.

RESULTS

In period 1, 53 surgical parathyroidectomy were performed (2.78/year, 0 to 5, 8.5/1000 patients-year) vs.56 surgical parathyroidectomy in period 2 (2.8/year, 0 to 9, 8/1000 patients-year). The patients of the 2 periods were comparable except for the higher dialysis vintage in period 1 (149±170 vs.89±94 months; P=0.02). In comparison with dialysis patients not requiring surgical parathyroidectomy during the same period, patients who had surgical parathyroidectomy were younger, had higher dialysis vintage and lower diabetes prevalence, but more frequently carriers of glomerulopathy or polycystosis. Systematically performed in period 2, cervical ultrasound identified at least one visible gland in 78.6% of cases while the scintigraphy, performed only in 66% of cases, found at least one gland in 81% of cases. Twelve months after surgery, PTH > 300 pg/mL (marker of secondary hyperparathyroidism recurrence or surgery failure) was present in 30% of patients in period 1 vs. 5.3% in period 2. Hypoparathyroidism was also more frequently observed in period 2 (35.7 vs. 18.8%). Surgical complications were also higher in period 1.

CONCLUSION

Despite therapeutic and strategic advances, severe secondary hyperparathyroidism is still as common as ever. It is favored by excessively high PTH targets, by suboptimal prevention before dialysis and poor tolerance of calcimimetics. The surgical parathyroidectomy is effective and safe in the hands of a specialized team with an ultrasound and scintigraphic preoperative assessment.

Multiglandular Parathyroid Disease: the Results of Surgical Treatment

Background. Sporadic multiple gland disease in primary hyperparathyroidism occurs in 7 to 33 % of cases. The absence of specific risk factors, low sensitivity of imaging methods, and low efficiency of bilateral neck exploration and intraoperative monitoring of parathyroid hormone indicate the complexity of the diagnosis and treatment of this disease’s form. Aim of the research. To analyze the results of surgical treatment of multiple lesions of the parathyroid gland in primary and secondary hyperparathyroidism. Methods. There was retrospective study, which included 100 observations of surgical treatment for primary and secondary hyperparathyroidism in the thoracic department of Irkutsk Regional Clinical Hospital from May 2018 to September 2019. The main point was to identify the frequency of surgical treatment outcomes in patients with multiple parathyroid lesions. As part of the study, potential predictors of multiple gland disease in primary hyperparathyroidism were analyzed. Results. Multiple gland disease in primary hyperparathyroidism occurs in 29 % of cases and causes persistence of the disease (p ≤ 0.01). Signs of multiple gland disease in primary hyperparathyroidism include the level of ionized calcium, parathyroid hormone (p ≤ 0.05), creatinine level and glomerular filtration rate (p ≤ 0.01). A negative result of intraoperative monitoring correlates with persistence of primary hyperparathyroidism in multiple lesions (χ2, p ≤ 0.05). Selective parathyroidectomy is associated with persistence of hyperparathyroidism in multiple lesions (χ2, p ≤ 0.05), while total parathyroidectomy is associated with remission of the disease (χ2, p ≤ 0.05). We did not find a statistically significant relationship between the results of surgical treatment for morphology of the parathyroid glands (χ2, p > 0.1). Conclusion. Multiple gland disease is the main cause of persistence of primary hyperparathyroidism. This form of the disease corresponds to lower levels of calcium, parathyroid hormone, and kidney function. Persistence factors have been established: removal of less than four parathyroid glands and a negative result of intraoperative monitoring of parathyroid hormone. Bilateral neck exploration does not reduce the incidence of disease persistence.

Hypocalcemia after ultrasound-guided microwave ablation and total parathyroidectomy for secondary hyperparathyroidism: a retrospective study

OBJECTIVE

To compare the postoperative hypocalcemia between ultrasound-guided microwave ablation (MWA) and total parathyroidectomy (TPTX) for secondary hyperparathyroidism (SHPT).

METHODS

The retrospective study reviewed 286 SHPT patients (171 received MWA and 115 underwent TPTX) between March 2018 and May 2019. Propensity-score matching was used to assemble a cohort of patients with similar baseline characteristics. A total of 184 SHPT patients (92 in each group) were finally enrolled, the occurrence and prognosis of postoperative hypocalcemia were compared. And the risk factors associated with severe hypocalcemia (SH) in each group were analyzed.

RESULTS

Hypocalcemia encountered in 95cases (49 in the MWA group and 46 in the TPTX group). SH occurred in 76 cases (40 in the MWA group and 36 in the TPTX group). There were no statistically significant differences in the detection time, incidence, minimum value of serum calcium and symptomatic hypocalcemia between MWA and TPTX group (all p values > 0.05). Of patients developing hypocalcemia, serum calcium did not recover to normal range in 5 cases (10.2%) in the MWA group, while 13 cases (28.3%) were still hypocalcemia at 6 months follow-up in TPTX group (p = 0.035). The time to recovery from hypocalcemia in the TPTX group (mean 30 days, range 3-180 days) was longer than the WA group (mean 14 days, range 3-126 days) (p = 0.000). High serum alkaline phosphatase (ALP) level and low serum calcium level were the main risk factors of postoperative SH.

CONCLUSION

There was no difference in hypocalcemia between MWA and TPTX group. Hypocalcemia in the TPTX group might need a longer time to recover.

Risk Factors of Severe Hypocalcemia After US-Guided Percutaneous Microwave Ablation of the Parathyroid Gland in Patients with Secondary Hyperparathyroidism

Our aim was to identify potential risk factors associated with severe hypocalcemia (SH) after microwave ablation (MWA) in patients with secondary hyperparathyroidism (SHPT). This retrospective cross-sectional study enrolled 204 consecutive patients (with 387 parathyroid glands) who underwent MWA between July 2015 and May 2018. Clinical parameters, laboratory indices, and parathyroid gland characteristics were analyzed to assess risk factors associated with SH after MWA. SH was defined as serum calcium level lower than 1.875 mmol/L (7.5 mg/dL) after MWA. Two models (I and II) for pre-MWA and post-MWA prediction were established, respectively. In accordance with the KDIGO guidelines, the target value for intact parathyroid hormone (iPTH) less than 300 pg/mL within 7 days after MWA was considered as a successful procedure. The success rate of MWA was 71.6% (146/204). The incidence of hypocalcemia and SH after MWA was 35.8% and 22.06%, respectively. The pre-MWA prediction models I and II showed that high pre-MWA iPTH, a dramatic reduction in iPTH, low pre-MWA serum calcium, multiple ablated gland, and lack of pruritus symptoms were risk factors for developing SH. The accuracy (82.23% versus 83.25% in models I and II, respectively), sensitivity (34.88% versus 44.19%), specificity (95.45% versus 94.59%), positive predictive value (PPV) (68.18% versus 70.37%), and negative predictive value (NPV) (84% versus 85.37%) of both models were promising. The logistic regression fitting of the nomograms showed high prediction efficiency (0.845 and 0.863). High pre-MWA iPTH, dramatic reductions in iPTH, low pre-MWA serum calcium, multiple gland ablation, and no pruritus symptoms were predictors of SH. © 2019 American Society for Bone and Mineral Research.

Parathyroidectomy in dialysis patients: Indications, methods, and consequences

Secondary hyperparathyroidism, characterized by increased PTH synthesis and secretion, is often seen in advanced stages of chronic kidney disease. Excessive proliferation of parathyroid cells leads to the development of diffuse hyperplasia that subsequently progresses to nodular histology. Refractory hyperparathyroidism occurs when parathyroid glands fail to respond to medical therapy. Parathyroidectomy (PTX), surgical resection of parathyroid glands, is usually performed in cases of persistent serum levels of PTH above 1000 pg/mL associated with hypercalcemia or when hyperparathyroidism is refractory to conservative therapy. Parathyroidectomy can be carried out using different procedures: subtotal PTX or total PTX with or without parathyroid autotransplantation. Parathyroid surgery may have undesirable consequences due to PTH oversuppression, such as the development of adynamic bone disease; hungry bone syndrome is quite common after this surgery. However, PTX improves survival and parameters of mineral metabolism. Parathyroidectomy needs to be considered in those patients with severe hyperparathyroidism with a poor response to pharmacological treatment and with distinct undesirable effects of PTH on bone and mineral metabolism parameters.

Survival after parathyroidectomy in chronic hemodialysis patients with severe secondary hyperparathyroidism

INTRODUCTION

The life for end-stage renal disease patients has remarkably improved in the last years. Although mineral and bone disorders remain as unsolved complication, in severe secondary hyperparathyroidism (sHPT), the ultimate treatment is parathyroidectomy (PTX). It is an old treatment, but there are still insufficient data regarding survival after PTX. The study goals were to compare 2-year mortality and morbidity after PTX in surgically versus medically treated sHPT and to compare the efficacy and safety in subtotal versus total PTX in a cohort of patients receiving hemodialysis (HD).

METHODS

This prospective, longitudinal study was carried out on a cohort of chronic HD patients with severe sHPT (iPTH over 700 pg/ml). Among the overall HD population, 26 patients underwent PTX. This group was compared to a control group treated with specific drugs. Laboratory parameters, specific symptoms and mortality were registered after 24 months of follow-up for each group. The subgroups of subtotal and total PTX patients were also compared.

RESULTS

All average values of mineral markers were significantly reduced after PTX, as a proof that surgical treatment was effective. The reduction in mineral markers and the improvement in symptoms and mortality rates were similar after total and subtotal PTX. Bone pain was significantly lower in patients after PTX than in those drug treated (p = 0.0005), but not muscle weakness and itching. Survival at 2 years was better in patients surgically treated (PTX) despite significantly higher mean baseline values of iPTH, Ca and ALP compared to patients medically treated (p = 0.03).

CONCLUSIONS

We compared clinical and laboratory outcomes in HD patients with severe sHPT. Mortality, bone pain and mineral markers were improved by PTX. Total and subtotal PTX had similar clinical outcomes.

Risk factors for severe hypocalcemia after parathyroidectomy in prevalent dialysis patients with secondary hyperparathyroidism

PURPOSE

Hypocalcemia is one of the common complications after parathyroidectomy (PTX). Severe hypocalcemia (SH) can lead to tetany, cardiac arrhythmia and even sudden death. However, predictors for the development of SH in patients with secondary hyperparathyroidism demonstrated in some small-scale studies with a limited sample size remain inconclusive.

METHODS

A retrospective chart review of 420 consecutive dialysis patients who underwent PTX during a 12-year period was performed. We checked serum levels of calcium (Ca), phosphorus (P), alkaline phosphatase (ALP) and intact parathyroid hormone (iPTH) for three consecutive days postoperatively. SH was defined as the minimum values of serum calcium lower than 1.875 mmol/L (7.5 mg/dL) within 3 days after operation.

RESULTS

The mean (±SD) age of our study population was 53 ± 12 years, and more than half (57 %) were female. SH occurred in 37 % of the patients after PTX. Using a multivariate stepwise logistic regression analysis, lower preoperative levels of Ca (odds ratio 0.69, 95 % CI 0.60-0.79, P < 0.001), higher preoperative levels of iPTH (odds ratio 1.04, 95 % CI 1.00-1.07, P = 0.048), P (odds ratio 2.43, 95 % CI 1.49-3.95, P < 0.001) and ALP (odds ratio 1.08, 95 % CI 1.05-1.11, P < 0.001) were found to be independent predictors of occurrence of SH following PTX.

CONCLUSIONS

The readily obtainable preoperative laboratory parameters including Ca, iPTH, P, and ALP will allow identification of a subgroup of patients who are at greater risk for the development of SH following PTX.