Treatment of refractory secondary hyperparathyroidism with ethanol injection: the importance of glandular volume

Safety and efficiency of microwave ablation for recurrent and persistent secondary hyperparathyroidism after parathyroidectomy: A retrospective pilot study

BACKGROUND

Recurrent and persistent secondary hyperparathyroidism (SHPT) nodules have an incidence of 10-70% after surgery. The treatment of recurrent and persistent SHPT nodules is a challenge, and surgical resection of difficult-to-reach or post-operative adhesions often fails.

PURPOSE

The aim of this research was to study the safety and effectiveness of microwave ablation (MWA) for recurrent and persistent SHPT.

MATERIALS AND METHODS

This was a retrospective study of 11 patients enrolled with a total of 16 nodules, and MWA was employed to manage SHPT. The laboratory test results, including the intact parathyroid hormone (iPTH), serum calcium, phosphorus and alkaline phosphatase (ALP) levels, improvement of SHPT-related symptoms after ablation, and complications during and after MWA were recorded and analysed.

RESULTS

After ablation the value of iPTH was markedly decreased from 1570 ± 1765 pg/mL to 287 ± 239 pg/mL 1 day after MWA (p < 0.05). The levels of serum calcium and phosphorus decreased from 2.51 ± 0.23 mmol/L to 2.06 ± 0.27 mmol/L (p < 0.001) and 1.80 ± 0.43 mmol/L to 1.48 ± 0.32 mmol/L (p < 0.05), respectively, 1 day after MWA. There was no significant difference in the ALP value before and after MWA (p > 0.05). The clinical symptoms, including ostalgia, pruritus, disability, and restless legs, improved after MWA. Minor complications and side effects encountered during or after MWA include haematoma (1/11, 9%), transient hoarseness (2/11, 18.2%), hypocalcemia (6/11, 54.5%). No major complication occurred.

CONCLUSION

MWA may be safe and effective to manage recurrent and persistent SHPT nodules; a definite conclusion needs to expand the sample size with a longer follow-up time.

Local ethanol injection for the treatment of deltoid parathyroid cell hyperplasia

Secondary hyperparathyroidism (SHPT) is a serious complication in dialysis patients and is routinely managed with medical therapy. Refractory disease is usually treated either surgically or by local ethanol injection into the parathyroid glands. Total parathyroidectomy with deltoid implant can be successful; however, recurrent, resistant disease is not uncommon. Local ethanol injection was applied to the deltoid autoimplant of a patient with recurrent, resistant SHPT, which had not been resolved with surgical treatment. Serum intact parathyroid hormone (iPTH) levels subsequently decreased from 1,400 to 219 pg/dl and remained stable for the next 6 months. To our knowledge, this procedure has not been previously described in the literature. Local injection of ethanol may represent an interesting alternative to surgery for the treatment of deltoid parathyroid cell hyperplasia in patients in which surgical treatment is not an option.

New options for the management of hyperparathyroidism after renal transplantation

The persistence and severity of hyperparathyroidism (HPT) post-renal transplantation is relatively frequent and primarily associated with the timing and its magnitude in the pre-transplant period and with the presence of parathyroid adenomas. HPT after renal transplantation is clinically manifested with hypercalcemia, hypophosphatemia, bone pain, fractures, and in more serious cases with cardiovascular calcifications that affect the survival. The primary clinical objective for patients with secondary HPT after renal transplantation is to obtain a level of parathyroid hormone (PTH) adequate to the renal transplanted function and to normalize levels of calcium, phosphorus and vitamin D. In many cases during this period, the development of hypercalcemia and/or hypophosphatemia makes it necessary to take different therapeutic measures. The use of vitamin D or its analogues has been extrapolated from the management of pre-transplant HPT obtaining variable outcomes, although its use is limited by its capacity to produce hypercalcemia. Calcimimetics are drugs that have proven be effective in reducing PTH levels in patients with HPT on dialysis and has been effective in reducing up to 50% PTH levels in moderate to severe HPT in post-renal transplantation.When HPT persists after renal transplantation and does not respond to medical treatment, invasive management by percutaneous ethanol injection therapy of parathyroid glands or parathyroidectomy should be considered. The emergence of new methods for the management of HPT expands the availability of therapeutic tools for transplant patients.

Use of percutaneous ethanol injection therapy for recurrent secondary hyperparathyroidism after subtotal parathyroidectomy

We evaluated the efficacy of percutaneous ethanol injection therapy (PEIT) as a therapeutic option for recurrence of secondary hyperparathyroidism after subtotal parathyroidectomy in ESRD patients. Six patients underwent PEIT. A mean of 1.3 ± 0.8 ethanol injections was performed. Nodular volume was 1.5 ± 1.7 cm³, and 2.8 ± 2.8 cm³ of ethanol was injected per patient. After ethanol injection PTH decreased significantly (1897 ± 754 to 549 ± 863 pg/mL (P < .01)). There was also a reduction in serum calcium, phosphorus and calcium-phosphorus product. A positive and significant correlation was found between nodular volume with ethanol injected and time from parathyroidectomy. Only one patient required hospitalization due to severe hypocalcaemia. In other two cases, local discomfort and temporary mild dysphonia were registered. PEIT is an effective treatment to control recurrences of secondary hyperparathyroidism postsubtotal parathyroidectomy.

Role of the parathyroid gland vascularization index in predicting percutaneous ethanol injection efficacy in refractory uremic hyperparathyroidism

AIMS

To evaluate the role of the quantitative vascularization index (VI) as a measure of the completeness of percutaneous ethanol injection therapy (PEIT).

METHODS

A total of 37 dialysis patients with secondary hyperparathyroidism refractory to medical therapy received PEIT. We analyzed the role of a quantitative marker of parathyroid adenoma activity, i.e. VI, flow index and vascular flow index as measured by 3-dimensional Doppler ultrasound with a 3-dimensional histogram software, for all patients before treatment and at 1 month and 6 months after PEIT.

RESULTS

Serum intact parathyroid hormone (i-PTH) level showed a strong positive correlation with the VI both before (p < 0.001) and after (p < 0.001) PEIT. There was no correlation between i-PTH level and the volume of the gland either before (p = 0.697) or after (p = 0.564) PEIT. One month after PEIT, 20 patients (group 1) reached the target of i-PTH ≤ 300 pg/ml and 17 patients (group 2) did not. Group 2 patients had significantly greater VI and i-PTH prior to PEIT than group 1 patients (42.23 ± 8.38 vs. 14.95 ± 8.07, p <0.001 and 1,447 ± 243 vs. 859 ± 231, p < 0.001 respectively).

CONCLUSION

A higher VI indicates a higher i-PTH, and the VI may be a reliable predictor of the completeness of PEIT.

Assessment of parathyroid glands in hemodialysis patients by using color Doppler sonography

The aim of this study was to assess the role of color and spectral Doppler ultrasound (CDU) in the evaluation of enlarged parathyroid glands in hemodialysis patients with secondary hyperparathyroidism. Fourteen hemodialysis patients with elevated intact parathyroid hormone (iPTH) levels were evaluated prospectively with CDU. The volume of each observed parathyroid gland and the spectral CDU data (velocities, resistance and pulsatility indices, systolic to diastolic ratio, and flow volume output (FVO)) were noted. The biochemical data (iPTH, calcium, phosphate levels), and CDU results were analyzed with the Spearman correlation test. Two patients were excluded, and 27 enlarged parathyroid glands were observed in 12 patients. The mean total volume of enlarged parathyroid glands per patient was 1.95 cm(3) (0.06-5.5 cm(3)). Arterial supply was demonstrated in 78% (21/27) of enlarged parathyroid glands. Mean total FVO of enlarged glands per patient was 238.5 ml/min (620-0 ml/min) and mean iPTH level was 1,477 pg/ml (643-3,132 pg/ml). The positive correlations of total volume (p = 0.022), iPTH (p = 0.024), and FVO (p = 0.022) were statistically significant. In secondary hyperparathyroidism, total volume of the visualized enlarged parathyroid glands and the total of FVOs per patient are positively correlated with iPTH levels which may help clinical management and follow-up of end-stage renal disease patients.

Clinical features and hyperplastic patterns of parathyroid glands in hemodialysis patients with advanced secondary hyperparathyroidism refractory to maxacalcitol treatment and required parathyroidectomy

We have previously suggested that when parathyroid glands progress to nodular hyperplasia, secondary hyperparathyroidism (2HPT) may be refractory to medical treatments, including treatment with Maxacalcitol (OCT). In the present study we evaluated the clinical features and hyperplastic patterns of parathyroid glands in patients who underwent parathyroidectomy (PTx) after being withdrawn from OCT. One hundred and eighty-seven advanced 2HPT patients who had been withdrawn from OCT and required PTx were enrolled. At the start of OCT treatment, the patients had a mean age of 55.3 years and had been receiving hemodialysis (HD) for a mean period of 149 months. At the start of OCT treatment and at PTx, the mean intact PTH (i-PTH) levels were 772.8 +/- 446.0 and 855.5 +/- 420.5 pg/mL, respectively. The main reasons for withdrawal of OCT treatment were persistently high PTH (n = 148), hypercalcemia (n = 79), hyperphosphatemia (n = 65), and progressive symptoms (n = 60). We classified the parathyroid glands by hyperplastic pattern into four categories: diffuse hyperplastic gland (D), early nodularity in diffuse hyperplastic gland (EN), nodular hyperplastic gland (N), and single nodular gland (SN). The mean total excised gland weight was 2592.6 mg. Out of a total of 706 glands, 118 were classified as D, 66 as EN, 436 as N, and 86 as SN. All patients had at least one nodular hyperplastic gland or single nodular gland. The mean number of nodular hyperplastic glands and/or single nodular glands was 2.9. All hemodialysis patients with advanced OCT-refractory 2HPT who underwent PTx had at least one nodular hyperplastic gland or single nodular gland.

Is the volume of the parathyroid gland a predictor of Maxacalcitol response in advanced secondary hyperparathyroidism?

We evaluated the relationship between the volume of parathyroid glands estimated by ultrasonography (US) and response of 22-oxa calcitriol (Maxacalcitol, OCT) in patients with secondary hyperparathyroidism (2HPT) to evaluate whether the volume can be a predictor of the OCT response. Eleven institutes participated in this study. Ninety-four patients with advanced 2HPT were enrolled. The volume of the parathyroid glands were estimated by US before and 6 months after OCT treatment. The response of OCT treatment was classified into three groups (Group A: i-PTH < 300 pg/mL; Group B: 300 pg/mL < or = i-PTH < 500 pg/mL; Group C: i-PTH > or = 500 pg/mL). Forty-eight patients were in Group A, 28 patients in Group B, and 18 patients in Group C. The PTH levels at the beginning and 6 months were 458.3-199.1 pg/mL (P < 0.0001) in Group A, 524.6-403.2 pg/mL (P = 0.007) in Group B and 736.7-613.6 pg/mL (ns) in Group C, respectively. The volume of the largest gland in Group B was significantly larger than that in Group A (96.2 vs. 343.2 mm3: P < 0.001). Clinical factors affecting response of OCT was evaluated by logistic regression analysis and only the volume of the largest gland was a significant factor. In the patients whose volume was less than 300 mm3, the OCT response was significantly effective. We conclude that the glandular volume of the largest parathyroid gland estimated by US can be a useful factor to predict the OCT response in patients with moderate or severe renal HPT.

Treatment of Secondary Hyperparathyroidism With Ultrasonographically Guided Percutaneous Radiofrequency Thermoablation

We present a case of a 63-year-old woman with a recurrent secondary hyperparathyroidism hyperplasia with absolute contraindication for surgery, treated in 2 sessions with percutaneous ultrasonographically guided radiofrequency tissue ablation. The complete pathologic tissue ablation was confirmed by contrast-enhanced ultrasonography performed before and after the treatment and by clinical and laboratory follow-up. Furthermore in work progress, the percutaneous ultrasonographically guided radiofrequency tissue ablation can be considered a feasible and effective nonsurgical alternative treatment for symptomatic secondary hyperparathyroidism in high-risk patients.

Treatment of uremic hyperparathyroidism with percutaneous ethanol injection

The percutaneous ethanol injection (PEI) with ultrasound guidance has been suggested for the treatment of patients with hyperparathyroidism who are on dialysis, with the aim of selectively treating the parathyroid glands with nodular hyperplasia. We present our experience in 25 patients with chronic renal failure followed during 13.4 +/- 10.6 months. A decrease in the levels of parathormone (PTH) (1,236.32 +/- 129.8 vs. 721.66 +/- 142.24 pg/ml), phosphatemia (6.16 +/- 0.35 vs. 4.93 +/- 0.36 mg/dl) and calcium-phosphorous product (60.82 +/- 3.81 vs. 46.47 +/- 3.46 mg2/dl2) was verified. In 56% of patients, PTH levels decreased (>50% of the baseline value) and 36% had final values <300 pg/ml. Patients in whom ultrasound showed a single gland responded better than those with more than one gland (83.3 vs. 30.8% of responders in each group). The procedures performed had a 4.9% complication rate: hematoma, symptomatic hypocalcemia, temporary paresis of the vocal cords. In summary, treatment with PEI is useful for the management of patients with hyperparathyroidism who are on dialysis, and the results achieved are better in patients who have a single gland identified by ultrasonography.

Different patterns of renal osteodystrophy in Iberoamerica

The various forms of renal osteodystrophy are predominant hyperparathyroid bone disease, mixed uremic osteodystrophy, low turnover osteomalacia, and adynamic bone disease. The present study analyses a total number of 1,209 bone biopsies from 5 different countries (Brazil, Uruguay, Argentina, Portugal, and Spain). Low turnover osteomalacia and mixed uremic osteodystrophy were more common in Brazil, Uruguay, and Argentina than in Portugal and Spain whereas predominant hyperparathyroid bone disease was seen more often in Portugal and Spain. In all centers, independent of the aluminum staining technique used, the extent of aluminum deposited in bone was greater in patients presenting with low bone turnover, whether from low turnover osteomalacia or adynamic bone disease, than in the predominant hyperparathyroid bone disease. In summary, even though recent reports have indicated that, over the last decade, the incidence of aluminum-induced toxicity was reduced, aluminum still seems to be implicated in a great percentage of symptomatic low bone remodelling lesions in Iberoamerica.