Total parathyroidectomy with forearm autograft for secondary hyperparathyroidism in chronic renal failure

Network meta-analysis of surgical treatment for secondary hyperparathyroidism

BACKGROUND

Main surgical treatments for secondary hyperparathyroidism (SHPT) include subtotal parathyroidectomy (sPTX), total parathyroidectomy with autotransplantation (tPTX+AT), and total parathyroidectomy (tPTX); however, determining the best treatment is debatable. We conducted a network meta-analysis (NMA) comparing three treatments in terms of postoperative hypocalcemia (or hypoparathyroidism), postoperative recurrence, and reoperation.

METHODS

We searched PubMed, Medline, the Cochrane Library, and Embase for relevant research from inception to July 30, 2019. We performed our Bayesian NMA using R 3.51 software to assess odds ratios (OR) and 95% confidence intervals (CI). Network and forest plots displayed study outputs. Potential publication bias was assessed with funnel plots using software Stata/MP 13.0.

RESULTS

Twenty-six articles comprising 5063 patients were included in our NMA, which showed that postoperative hypocalcemia (or hypoparathyroidism) occurred more frequently in tPTX than in sPTX (OR = 3.50, 95% CI 1.10-11.0) or tPTX+AT patients (OR = 1.80, 95% CI 0.66-5.20). Regarding postoperative hypocalcemia (or hypoparathyroidism), there was no significant difference between sPTX and tPTX+AT (OR = 0.53, 95% CI 0.24-1.10). As for recurrence rates, statistically significant differences were observed between sPTX and tPTX (OR = 25.0, 95% CI 5.1-260), tPTX+AT and tPTX (OR = 20.0, 95% CI 4.2-200), and sPTX and tPTX+AT (OR = 1.30, 95% CI 0.65-2.50). Regarding reoperation rates, sPTX experienced higher incidence compared with tPTX+AT (OR = 1.20, 95% CI 0.53-2.70) or tPTX patients (OR = 2.70, 95% CI 1.20-14.00).

CONCLUSIONS

TPTX+AT is recommended as the most efficient and safe surgical SHPT treatment with minimal adverse effects. Large-scale randomized controlled trials are recommended to confirm the NMA results.

Ultrasonography for preoperative localization of enlarged parathyroid glands in secondary hyperparathyroidism

OBJECTIVE

Parathyroidectomy (PTx) is sometimes performed to treat secondary hyperparathyroidism (2HPT) related to long-term dialysis. In this procedure, all four parathyroid glands should be resected. However, in patients with 2HPT, the four glands are not uniformly enlarged; therefore, preoperative diagnosis is difficult in comparison with primary hyperparathyroidism. We compared glands detected on preoperative ultrasonography (US) with those resected during PTx to examine the usefulness and limitations of US.

METHODS

The subjects were 44 patients with 2HPT who underwent PTx between December 2003 and November 2007. Surgery was indicated for patients meeting the following three conditions: a serum intact PTH (iPTH) level of 500 pg/ml or more; a maximum glandular volume of 500 mm3 or more; and increased bone metabolism. Before surgery, we detected the parathyroid glands using US, and three-dimensionally measured their sizes. PTx was performed based on US diagnosis, and resected glands were weighed.

RESULTS

Assuming that four parathyroid glands are present in each patient, the total number of glands in the 44 patients was 176. Of the 176 glands, 139 were detected on preoperative US. However, 27 could not be resected. Therefore, the detection rate on US was 63.6% (112/176). Of 37 glands that could not be detected on preoperative US, 30 were detected during surgery, and resected. There was a positive correlation between the glandular volume measured on US and isolated gland weight. However, there was no correlation between the preoperative serum iPTH level and the sum of the four isolated gland weights.

CONCLUSION

On preoperative US, approximately 80% of the glands were detected. However, the misdiagnosis rate was approximately 20%. The rate of accurate diagnosis was 63.6%. Even when glands were misdiagnosed or could not be confirmed on preoperative US, approximately 80% of them could be detected and resected during surgery. It may be impossible to estimate the glandular volume based on the preoperative serum iPTH level.

Surgical treatment of secondary hyperparathyroidism due to chronic kidney disease

It is a great honour for me to have this opportunity to present a review about surgical treatment of secondary hyperparathyroidism (2HPT) due to chronic kidney disease (CKD). Uppsala is a historical place concerning the parathyroid gland, because it was here that Ivar Sandström in 1877 initially discovered the small organs, Glandulae Parathyroideae, existing around the thyroid gland in human beings. This finding led to intensive studies of the parathyroid glands, focusing on their histopathology, pathophysiology, clinical diagnosis, and medical and surgical treatment (1) and investigations are still continuing in Uppsala today. I had the privilege to stay in Uppsala during 1989 to study the surgery and pathology of parathyroid glands and it was a pleasure to share clinical and basic research about these small and charming organs with my colleagues in Uppsala.

Cervical epidural anesthesia for combined neck and upper extremity procedure: a pilot study

In a prospective pilot study, we evaluated the possibility of performing a total parathyroidectomy with parathyroid gland implantation into the forearm (a combined neck and upper extremity procedure) under cervical epidural anesthesia (CEA) at C6-7 level using ropivacaine. The indication for CEA was the patient's choice or a previous procedure on the neck with unilateral vocal cord paralysis. Anesthesia was induced by 10 mL of 0.75% ropivacaine plus 10 mug of sufentanil in 2 mL. Block onset time, success rate, analgesia, sensory block extent, changes in respiratory and hemodynamic variables, complications, and length of hospital stay were assessed. All 15 procedures were successfully performed under CEA. Sensory block was registered in the range C2-T10, with a lower median of T3. The upper margin of sensory block was C2 in all patients. Of the respiratory variables, the only significant decrease was observed in forced vital capacity; none of the patients developed clinically significant respiratory insufficiency. We conclude that combined procedures involving the neck and upper limbs can be performed using CEA with ropivacaine. CEA allows verbal communication with patients and early detection of vocal cord paralysis.

Early effects of parathyroidectomy on erythropoietin production in secondary hyperparathyroidism

BACKGROUND

Secondary hyperparathyroidism (2-HPT) has an adverse effect on renal anemia and may cause a hyporesponsiveness to recombinant human erythropoietin (rHuEpo) in patients with chronic renal failure. The early effects of parathyroidectomy (PTx) on renal anemia, erythropoietin production, and nutritional state were examined.

METHODS

Twenty-nine patients under hemodialysis therapy received a PTx for 2-HPT. They were prospectively studied regarding hematological parameters, rHuEpo use, plasma erythropoietin levels, and nutritional condition until 12 months after PTx.

RESULTS

The hemoglobin level showed a significant increase from 3 months after PTx (10.2% +/- 1.5% to 11.2% +/- 1.3%; P <0.01), associated with a consistent increase of the reticulocyte count. These changes lasted until 12 months after PTx. The plasma erythropoietin level showed a gradual increase of up to about 5 times the level of the preoperative value, until 12 months after PTx (22.6 +/- 10.1 to 106.3 +/- 112.1 mU/mL; P <0.001). The weekly dose of rHuEpo administration decreased after 3 months. The serum levels of albumin and total protein also significantly and gradually improved until 12 months after PTx.

CONCLUSIONS

PTx caused a significant early improvement in renal anemia in patients with secondary hyperparathyroidism. This effect may be caused by an enhanced erythropoietin production and may also be partially due to the improved nutritional state after PTx.

More than 1,000 cases of total parathyroidectomy with forearm autograft for renal hyperparathyroidism

Between March 1981 and December 2000, we performed 1,053 total parathyroidectomies with forearm autograft for advanced renal hyperparathyroidism (HPT). Based on histopathologic and pathophysiologic investigations, surgical treatment should be considered when parathyroid glands show nodular hyperplasia. Measuring parathyroid volume by ultrasonography was useful to detect nodular glands and to determine surgical indications. The clinical effect of parathyroidectomy on the symptoms and biochemical variables was striking. Skeletal deformity, progressive bone loss, and vessel calcification leading to high mortality risk could not be alleviated by even successful surgery, however. To prevent cardiovascular complications, parathyroidectomy should be performed in the relatively early stage of renal HPT. Total parathyroidectomy with forearm autograft is a suitable procedure for renal HPT, especially in patients who require long-term hemodialysis. For surgeons, it is important to remove all parathyroid glands, including supernumerary glands, at the initial operation and to choose adequate parathyroid tissue for the autograft to prevent persistent and recurrent HPT. Although the risk of graft-dependent recurrent HPT is not negligible, enlarged transplanted parathyroid tissue can be removed easily and noninvasively from the forearm under local anesthesia. There is no risk of hypofunction of the autograft.

Subcutaneous forearm transplantation of autologous parathyroid tissue in patients with renal hyperparathyroidism

BACKGROUND

Parathyroidectomy is required in up to 5% of patients with chronic renal failure. Intramuscular transplantation of autologous parathyroid tissue in the forearm has been the traditional method of transplantation at the time of total parathyroidectomy. The removal of an intramuscular transplantation can be technically difficult should graft-dependent hyperparathyroidism (GRH) occur. This problem resulted in our initiating a study of subcutaneous transplantation with total parathyroidectomy in patients with renal failure.

METHODS

Twenty-six patients who were receiving dialysis therapy underwent total parathyroidectomy and subcutaneous transplantation. Parathyroid tissue was diced into 1- to 2-mm pieces, and 6 pieces were grafted into 6 subcutaneous pockets of the forearm. Intact parathyroid hormone was measured within 48 hours of operation and in the bilateral antecubital veins 1 to 24 months after the operation to assess completeness of resection and graft function, respectively.

RESULTS

No major surgical complications occurred. Symptoms improved in 24 patients (85%). Graft failure rate was 4.3%. No GRH was observed. Follow-up was 4 to 55 months (mean, 27 months).

CONCLUSIONS

This study indicates that the subcutaneous transplantation function is comparable to intramuscular transplantation and suggests a decreased incidence of GRH. Subcutaneous transplantation is technically easier than intramuscular transplantation and has the additional advantage of easy removal should GRH occur.

Effects of a parathyroidectomy on the immune system and nutritional condition in chronic dialysis patients with secondary hyperparathyroidism

BACKGROUND

Parathyroid hormone (PTH) has an adverse effect on the immune system and may cause immunologic disorders in patients with chronic renal failure. The in vivo effects of a parathyroidectomy on the immunologic parameters was examined.

METHODS

Thirty-four patients under dialysis therapy received a parathyroidectomy (PTx) for secondary hyperparathyroidism (HPT). They were prospectively studied regarding serum immunoglobulins, complements, CD markers, and serum soluble IL-2 receptor (sIL-2R) until 12 months after PTx.

RESULTS

The serum levels of IgG, IgA and IgM showed significant increase until 12 months after PTx (P<0.001, respectively). C3, C4, and CH50 also indicated significant increase at 12 months after PTx. In cellular immunity, only serum sIL-2R showed significant increase 2 weeks after PTx (P = 0.028). The hematocrit and serum albumin also improved significantly at 12 months.

CONCLUSIONS

PTx showed beneficial effects on humoral immunological markers. The effects are probably due to the remarkable PTH reduction and partly improved nutritional state after PTx.

Prospective biochemical and scintigraphic evaluation of autografted normal parathyroid glands in patients undergoing thyroid operations

BACKGROUND

Parathyroid autotransplantation has been widely used in thyroid operations. Few studies have assessed the function of the autotransplanted glands. The aim of this study was to evaluate the success rate, pattern of biochemical function, and scintigraphic appearance of parathyroid autografts in patients undergoing thyroid operations.

METHODS

Twelve patients in whom 1 parathyroid gland was removed during thyroid operation were included. Glands were fragmented and autografted into individual pockets in the brachioradialis muscle of the nondominant forearm. Parathyroid hormone levels were measured in both arms the day of autotransplantation and 2 weeks and 1, 2, 3, and 6 months after operation. Serum calcium levels were also measured at each interval. Sestamibi scanning was performed 6 months after operation in 7 patients.

RESULTS

All patients were women with a mean age of 50 +/- 15 years. Serum calcium levels were normal during follow-up. A gradient of parathyroid hormone level of 1.5 or greater between the autotransplanted and nontransplanted arm was found in 10 patients. Isotope uptake at the site of the parathyroid autotransplant was demonstrated in the 7 patients evaluated.

CONCLUSIONS

Biochemical function of autotransplanted normal parathyroid tissue was documented in 83% of the patients. Sestamibi scintiscans were able to identify the autotransplanted tissue.

Parathyroidectomy in patients with chronic renal failure

BACKGROUND

Hyperparathyroidism is common in patients with renal disease. These patients may require operation for this disease if it cannot be controlled by medical therapy. Because these patients continue to have renal failure, the risk of recurrence and reoperation is high.

METHODS

Sixty-nine patients with renal failure underwent operation for hyperparathyroidism. These patients were followed up on dialysis or after transplantation.

RESULTS

Sixty-nine patients, aged 2 to 71 years old, with end-stage renal disease required parathyroidectomy for hyperparathyroidism 6.2 +/- 4.2 (standard deviation) years after beginning dialysis. Thirty-six patients had undergone renal transplantation (creatinine = 1.6 +/- 0.4 mg/dL). All patients had elevated parathyroid hormone (PTH) levels. Sixty-eight patients had hyperplasia; 1 patient had adenoma. Six patients required reoperation for recurrent hyperparathyroidism 30 to 123 months after their initial parathyroidectomy.

CONCLUSION

Patients with end-stage renal disease are prone to abnormalities of calcium metabolism. They frequently develop parathyroid hyperplasia. Recurrence can occur following operation because of continuing renal failure.

Surgical treatment of renal hyperparathyroidism

Advanced secondary (renal) hyperparathyroidism induced by chronic renal disturbance is one of the most serious complications for long-term hemodialysis patients. Parathyroidectomy is indicated in patients with severely advanced renal hyperparathyroidism refractory to medical treatment (including calcitriol pulse therapy) and the clinical effect of parathyroidectomy is striking. However, skeletal deformity, vessel calcification, and remarkable reduction of bone content is irreversible, and it is important to perform parathyroidectomy at right time. Based on histopathological and pathophysiological investigations, nodular hyperplasia is monoclonal neoplasia with abnormal parathyroid hormone (PTH) response to extracellular calcium and vitamin D. When parathyroid hyperplasia progresses to nodular hyperplasia, parathyroidectomy should be required. Total parathyroidectomy with forearm autograft is the preferable procedure for renal hyperparathyroidism, especially for patients who need to continue hemodialysis treatment after parathyroidectomy. Removal of all parathyroid glands, including supernumerary glands, at the initial operation, and proper choice of adequate parathyroid tissue for autograft, are important to prevent persistent and recurrent hyperparathyroidism. Preoperative image diagnosis is useful for localization, and routine resection of thymic tissue is necessary to remove supernumerary glands. In our series of 548 patients, graft-dependent recurrent hyperparathyroidism was not negligible and the incidence was about 20% at the 5th year postoperatively. Enlarged autografts of parathyroid tissue could be removed from forearm under local anesthesia with fewer invasions. The function of autografted parathyroid tissue is nearly satisfactory and no re-transplantation of cryopreserved parathyroid tissue was necessary. To avoid adynamic bone disease, relatively high PTH level is required-over-suppression of PTH by excess of vitamin D and calcium salts should be avoided. In our experience, total parathyroidectomy with forearm autograft is very effective and adequate treatment for advanced renal hyperparathyroidism, and parathyroid function can be controlled after parathyroidectomy.

Parathyroid function and bone metabolic markers in primary and secondary hyperparathyroidism

Remarkable changes of parathyroid function immediately after parathyroidectomy were evaluated in primary (PHPT) and secondary (RHPT) hyperparathyroidism. Bone metabolism was also evaluated by new specific markers of bone formation and resorption. A rapid decline into the undetectable range, and a rapid recovery of serum bioactive parathyroid hormone (PTH) concentrations were observed after parathyroidectomy in PHPT. Since the function of the remnant parathyroid glands was not clear, we investigated the transcription of PTH mRNA. Despite the suppression of PTH secretion in the remnant parathyroid glands, no significant difference was found in the amount of PTH mRNA present in an adenoma as compared to a remnant gland when evaluated by cytoplasmic dot hybridization and in situ hybridization. Although measurement of serum PTH concentration by assays of inactive fragment was available for the longterm follow-up of PTH function in RHPT, parathyroid function should be evaluated by biologically active intact PTH immediately after operation. The PTH gradient also was successfully evaluated by the measurement of intact PTH. A discrepancy was observed between bone resorption evaluated by type I collagen cross-linked N-telopeptide as compared to bone formation evaluated by osteocalcin immediately after operation. This discrepancy will improve and bone mineral density will increase in the first 6 months after parathyroidectomy.

Factors related to the recurrent hyperfunction of autografts after total parathyroidectomy in patients with severe secondary hyperparathyroidism

Total parathyroidectomy with autotransplantation has been widely accepted as the appropriate treatment for patients with hyperparathyroidism due to chronic renal failure on long term hemodialysis. However, recurrence has been an enigma and therefore, the factors involved in the recurrence of hyperparathyroidism were studied in 128 patients followed for more than 2 years after surgical treatment. The preoperative serum parathyroid hormone (PTH) concentrations correlated with the total weights of the parathyroid glands. When the original autotransplanted glands were divided into two groups, being diffuse and nodular, the rate of recurrent hyperparathyroidism due to graft hyperfunction was significantly higher in the patients who received nodular glands (24%) than in those who received diffuse glands (8.4%) (P < 0.05). To investigate whether PTH synthetic activity is different in diffuse and nodular glands, the amount of PTH mRNA was studied by in situ hybridization. There was no significant difference in the amount of PTH mRNA in the cells from either diffuse or nodular glands. These data suggest that the recurrence of hyperparathyroidism is not due to enhanced PTH synthetic activity of autotransplant grafts but to the abnormal growth rate of the transplanted gland.

Recurrent renal hyperparathyroidism and DNA analysis of autografted parathyroid tissue

In spite of recent therapeutic advances, severe overt secondary hyperparathyroidism due to chronic renal failure necessitates parathyroidectomy and recurrent hyperparathyroidism is one of the most significant problems in this patient population. In the present study, the incidence of recurrent hyperparathyroidism was evaluated in relation to the histopathological features. Image cytometric DNA analysis was performed to estimate the proliferative potential of parathyroid tissue. The study comprised 248 patients who underwent parathyroidectomy from 1973 to 1991. The frequency of recurrent hyperparathyroidism after subtotal parathyroidectomy was 4 (21.1%) of 19 patients, the rate of graft-dependent recurrence after removal of residual parathyroid tissue with forearm autograft was 2 (50%) of 4 patients. The frequency of graft-dependent recurrence after total parathyroidectomy with forearm autograft was 16 (7.5%) of 212 patients. The frequency of recurrence was significantly higher (p less than 0.01) when nodular hyperplastic parathyroid tissue was autografted (17 of 68 patients, 25%) than when diffuse-hyperplastic tissue was grafted (1 of 105 patients, less than 1%). All 58 specimens subjected to image cytometric DNA analysis showed a diploid nuclear pattern cytometrically. However, the relative number of scattered cells that displayed cytometric nuclear DNA values outside the main diploid histogram peak was significantly greater (p less than 0.01) in nodular hyperplastic tissue before being autografted and in parathyroid tissue removed at re-operation performed for recurrence than in diffuse hyperplastic tissue. These clinical findings and results of DNA analysis clearly indicated that nodular hyperplastic parathyroid tissue has a higher growth potential, and it is concluded that to prevent graft-dependent recurrence, the nodular type of hyperplastic tissue should not be autografted.