Transient rise in intact parathyroid hormone concentration after surgery for primary hyperparathyroidism

Efficacy and safety of radiofrequency ablation for primary and secondary hyperparathyroidism with or without previous parathyroidectomy: a retrospective study

INTRODUCTION

This study aimed to investigate and compare the therapeutic efficacy and safety of ultrasound-guided radiofrequency ablation (RFA), between primary hyperparathyroidism (PHPT) and secondary hyperparathyroidism (SHPT) patients, with or without previous parathyroidectomy (PTX).

SUBJECTS AND METHODS

A total of 21 patients (7 PHPT, 14 SHPT) underwent RFA for hyperparathyroidism (HPT) at Kaohsiung Chang Gung Memorial Hospital, Taiwan. Five of the 14 SHPT patients had previously received PTX. The laboratory data, volume change of each parathyroid nodule, symptomatic scores, and complications were analyzed and compared between all groups at 1 and 7 days, and at 1, 3, 6, and 12 months after RFA.

RESULTS

After RFA, the volume reduction ratio (VRR) for all patients at the last follow-up was 93.76%, and clinical symptoms significantly improved. At 12 months, all PHPT patients achieved successful treatment of intact PTH (iPTH). In SHPT patients, the mean iPTH value significantly decreased 1-day post-RFA, subsequently exhibiting a transient rebound which proceeded to decrease, with 57.1% reaching successful treatment standards. SHPT patients with PTX showed a lower complication score, shorter ablation time, higher iPTH baseline and outcomes, and lower VRR, compared to patients without PTX. The serum calcium level significantly decreased to normal range in 85.7% of all patients at 12 months. Severe hypocalcemia occurred in 23.8% at 1 week, and all were corrected with calcium supplements.

CONCLUSIONS

RFA demonstrates a therapeutic efficacy similar to PTX. It can thus be considered an effective alternative treatment for PHPT, SHPT, or post-PTX patients who are unsuitable for another PTX.

Analysis of the cause and management of persistent laboratory abnormalities occurring after the surgical treatment of primary hyperparathyroidism

Purpose

The surgical success rate for primary hyperparathyroidism (PHPT) is currently 95%–98%. However, 3%–24% of patients show persistently elevated (Pe) parathyroid hormone (PTH) levels after parathyroidectomy (PTX). This single-center retrospective study aimed to compare the outcomes of patients with normal PTH and PePTH levels after successful PTX and to identify the factors associated with PePTH.

Methods

The normal group, defined as patients with normal serum calcium and PTH levels immediately after PTX, was compared with the PePTH group (patients with normal or low serum calcium and increased serum PTH levels up to 6 months postoperatively) to determine the causes of disease in the PePTH group.

Results

There were no significant differences in age, sex, or preoperative estimated glomerular filtration rate between the normal PTH group (333 of 364, 91.5%) and the PePTH group (31 of 364, 8.5%). However, there were significant differences in preoperative 25-hydroxyvitamin D (17.9 and 11.8 ng/mL, respectively; P = 0.003) and PTH levels (125.5 and 212.4 pg/mL, respectively; P < 0.001) between the 2 groups. Among the 31 cases of the PePTH group, 18 were attributed to vitamin D deficiency.

Conclusion

Preoperative vitamin D deficiency is a predictive factor for PePTH. Therefore, preoperative administration of vitamin D supplements may reduce the probability of postoperative disease persistence. Patients with temporary laboratory abnormalities within 6 months after successful PTX should be monitored, and appropriate vitamin D and calcium supplementation may reduce the effort and cost of various examinations or reoperations.

Persistent Elevation of Parathormone Levels after Surgery for Primary Hyperparathyroidism

BACKGROUND

Persistent elevation of serum parathyroid hormone (PTH) despite normocalcemia have been documented in 8- 40% of patients after parathyroidectomy. We hereby report our experience from different centers across India to determine clinical significance of postoperatively elevated PTH levels and review relevant literature.

METHODS

We conducted a retrospective case series study and reviewed all the patients who underwent surgery for primary hyperparathyroidism (PHPT) from April 2010 to January 2020.

RESULTS

Total of 201 patients was diagnosed as PHPT. Out of available follow-up data of 180 patients, a total of 54 patients (30%) had persistently elevated PTH (PePTH) at 1 month. Patients with PePTH were older with higher preoperative serum calcium, iPTH, alkaline phosphatase and lower serum phosphate and 25-hydroxy vitamin D3 levels. Creatinine clearance was found to be significantly lower in patients with PePTH. Multiple linear regression analysis revealed that preoperative 25-OH D3 concentration, creatinine clearance and iPTH are the factors influencing persistent elevation of PTH levels. Significantly lower serum calcium and higher alkaline phosphatase levels were observed in PePTH patients with preoperative 25-OH D3 levels <20 ng/mL. Thirty patients at 6 months, 24 patients at 1 year, 18 patients at 2 years and 9 patients at 3 years had eucalcemic PTH elevation. Nine out of 126 (7%) patients with normal initial postoperative calcium and iPTH levels developed PePTH, with none culminating into recurrent hyperparathyroidism.

CONCLUSION

Though the pathogenesis of such a phenomenon still remains to be elucidated, a multifactorial mechanism appears to play a role.

[Primary hyperparathyroidism. Postoperative normocalcemic hyperparathyrinemia after curative parathyroidectomy]

INTRODUCTION

Normocalcemic hyperparathyrinemia, i.e. elevated parathyroid hormone (PTH) levels after parathyroidectomy in patients with primary hyperparathyroidism (pHPT) may occur in the course of postoperative recovery without the development of persistence or relapse.

MATERIALS, METHODS AND RESULTS

Intraoperative and long-term (7 year) postoperative PTH and calcium levels after curative parathyroidectomy are demonstrated on the basis of a case report of a 62-year-old female patient with severe pHPT and pronounced osseous and renal manifestations. The intraoperative PTH gradient displayed a decrease from 1072 pg/ml to 13 pg/ml (normal range 11-67 pg/ml) followed by an increase of up to 287 pg/ml. The hyperparathyoid values decline to subnormal levels on administration of calcium and vitamin D and increase again after tapering these medications. The inverse calcium/PTH correlation in the course of the 7-year observation period suggests an intact feed-back mechanism. Preoperative PTH screening was performed in 316 consecutive normocalcemic thyroid patients to evaluate the rate of incidental hyperparathyroidism in patients with normal serum calcium levels. Of these patients 31 (9.8%) with normocalcemia (average 2.28 mmol/l, normal range 2.1-2.7 mmol/l) exhibited increased PTH levels averaging 84.2 pg/ml. A parathyroid adenoma was found intraoperatively as the cause for normocalcemic pHPT in only 1 of these 31 patients.

DISCUSSION AND CONCLUSIONS

A review of the literature revealed that late postoperative elevated parathyroid hormone levels after successful pHPT surgery occur in 21.5%. Multiple causes are discussed, e.g. reactive hyperparathyroidism in cases of relative hypocalcemia, hungry bone syndrome, vitamin D deficiency, renal dysfunction and ethnic or lifestyle differences. In mild cases of postoperative hyperparathyrinemia observation of the patient may be sufficient. In cases of reactive hyperparathyroidism due to hypocalcemia, administration of calcium is indicated, in symptomatic patients, additional administration of vitamin D or calcitriol is necessary. Vitamin D deficiency per se needs adequate substitution. In cases of ongoing hyperparathyrinemia an interdisciplinary diagnostic and therapeutic approach is required.

The role of parathyroid hormone measurements after surgery for primary hyperparathyroidism

BACKGROUND

During parathyroidectomy for primary hyperparathyroidism (pHPT), intraoperative parathyroid hormone (IOPTH) levels are used to confirm removal of all hyperfunctioning parathyroid tissue. The phenomenon of elevated parathyroid hormone (PTH) levels with normocalcemia after curative parathyroidectomy, seen in up to 40% of patients, continues to be an unexpected and unexplained finding. We therefore investigated whether postoperative PTH levels are as reliable as IOPTH levels in predicting cure after surgery for pHPT.

METHODS

We reviewed our prospective database of consecutive patients undergoing surgery for pHPT between December 1999 and November 2004. Curative parathyroidectomy was defined as normocalcemia 6 months or longer postoperatively.

RESULTS

A total of 328 patients who underwent 330 operations for pHPT had IOPTH measurements and serum follow-up calcium levels at 6 months or longer. Surgery was curative in 315 (95.5%) operations. IOPTH levels correctly predicted operative success in 98.2% (positive predictive value [PPV]. Postoperatively, the PPV of a normal PTH level at 1 week, 3 months, and 6 months was 97.1%, 97.3%, and 96.5%, respectively. Of all patients with an elevated postoperative PTH level at 1 week, 3 months, or 6 months, only 13.7%, 14.3%, and 14%, respectively, were not cured.

CONCLUSIONS

Normal postoperative PTH levels reliably predict operative success. However, they do not improve upon results predicted by IOPTH levels. Elevated postoperative PTH levels do not predict operative failure in most patients. We propose that PTH measurements after surgery for pHPT may be misleading, costly, and not indicated in normocalcemic patients.

Persistently elevated parathyroid hormone levels after parathyroid surgery

BACKGROUND

Persistent elevation of serum parathyroid hormone (PTH), despite normocalcemia, occurs in 8% to 40% of patients after parathyroidectomy. Explanations have included hypocalcemia owing to vitamin D deficiency or bone remineralization, and persistent hyperparathyroidism.

METHODS

A retrospective chart review of 816 consecutive patients who underwent surgery for primary hyperparathyroidism was conducted.

RESULTS

One hundred fourteen patients (15%) had persistently elevated PTH levels (PPTH). Patients with PPTH had higher preoperative PTH levels than those with normal PTH levels postoperatively. They also had lower postoperative Ca(++) and vitamin D levels. Multiple gland enlargement was identified in fewer patients with PPTH than in those with normal postoperative PTH levels. In patients with PPTH and a postoperative Ca(++) less than 9.6 mg/dL (group I), there was a greater decrease in IOPTH, a higher initial postoperative PTH level, and a lower postoperative vitamin D level than in PPTH patients whose postoperative Ca(++) was > or =9.6 mg/dL (group II). Postoperative Ca(++) and vitamin D levels were also lower in patients whose PPTH did not ultimately resolve. Three patients in group II had recurrent disease.

CONCLUSIONS

Persistent elevation of postoperative serum PTH levels in normocalcemic patients is associated with mild hypocalcemia, probably owing to vitamin D deficiency. In some patients it may also be indicative of mild persistent hyperparathyroidism.

Reelevation of parathyroid hormone level after parathyroidectomy in patients with primary hyperparathyroidism: importance of decreased renal parathyroid hormone sensitivity

BACKGROUND

We hypothesized that impaired peripheral sensitivity to parathyroid hormone (PTH) may play a role in reelevation of PTH after successful operation for primary hyperparathyroidism (pHPT).

METHODS

Factors affecting reelevation of PTH were determined in 90 patients who underwent parathyroidectomy for pHPT. PTH/nephrogenous cyclic adenosine monophosphate ratio, as an index of renal resistance to PTH, was examined in relation to factors shown to influence reelevation of PTH.

RESULTS

Serum PTH levels were elevated above the upper limit of normal in 23 patients (26%) at 1 week and in 39 patients (43%) at 1 month after parathyroidectomy. These 39 normocalcemic patients with elevated serum PTH at 1 month after parathyroidectomy had a higher preoperative serum level of PTH and lower serum phosphate and 25-hydroxyvitamin D (25OHD) concentrations than those with normal PTH (n = 59). Elevated PTH and low 25OHD were shown by multivariate analysis to be significant predictors of reelevation of PTH. Renal resistance to PTH was higher in patients with vitamin D deficiency or renal insufficiency than in patients with normal serum vitamin D concentrations or normal renal function, and it increased according to increases in levels of PTH.

CONCLUSIONS

The mechanism of PTH reelevation in patients with pHPT after successful parathyroidectomy appears to be renal resistance to PTH.

A systematic review of the diagnosis and treatment of primary hyperparathyroidism from 1995 to 2003

OBJECTIVE

To systematically review the current preoperative diagnostic modalities, surgical treatments, and glandular pathologies associated with primary hyperparathyroidism.

STUDY DESIGN

A systematic literature review.

RESULTS

Of the 20,225 cases of primary hyperparathyroidism reported, solitary adenomas (SA), multiple gland hyperplasia disease (MGHD), double adenomas (DA), and parathyroid carcinomas (CAR) occurred in 88.90%, 5.74%, 4.14%, and 0.74% of cases respectively. Tc 99m -sestamibi and ultrasound were 88.44% and 78.55% sensitive, respectively, for SA, 44.46% and 34.86% for MGHD, and 29.95% and 16.20% for DA, respectively. Postoperative normocalcemia was achieved in 96.66%, 95.25%, and 97.69% of patients offered minimally invasive radio-guided parathyroidectomy (MIRP), unilateral, and bilateral neck exploration (BNE). Intraoperative PTH assays (IOPTH) were helpful in approximately 60% of bilateral neck exploration conversion (BNEC) surgeries.

CONCLUSION

The overall prevalence of multiple gland disease (MGD and DA) was lower than often suggested by conventional wisdom. Furthermore, preoperative imaging was less accurate than it is often perceived for accurately imaging MGD. MIRP and UNE were more successful in achieving normocalcemia than is typically quoted. IOPTH was a helpful but not "fool-proof" adjunct in parathyroid exploration surgery.

SIGNIFICANCE

These results support a greater role for the treatment of primary hyperparathyroidism using less invasive approaches. EMB rating: B-3.

Elevated serum parathyroid hormone concentration in eucalcemic patients after parathyroidectomy for primary hyperparathyroidism and its relationship to vitamin D profile

Elevation of serum parathyroid hormone (PTH) level in eucalcemic patients after parathyroidectomy for primary hyperparathyroidism has been described in up to 40% of patients, but little is known about its etiology or clinical significance. To better understand the cause of this phenomenon, we studied 49 patients without renal dysfunction or osteomalacia who underwent parathyroidectomy for primary hyperparathyroidism. Patients were categorized into 2 groups based on their serum PTH and calcium levels after parathyroidectomy: (1) elevated PTH with eucalcemia (n = 21), (2) normal PTH with eucalcemia (n = 28). Elevation of serum PTH with eucalcemia after parathyroidectomy occurred in 43% of patients. Patients in group 1 had significantly higher preoperative and postoperative mean serum PTH levels and significantly lower postoperative serum levels of 1,25(OH)(2)D(3), 1,25(OH)(2)D(3)/25(OH)D(3) ratio, and 1,25(OH)(2)D(3)/PTH ratio compared with patients in group 2. Serum PTH in group 1 patients normalized as early as 3 months, but remained elevated in some patients for more than 4 years, and was not associated with development of recurrent hypercalcemia. Normalization of serum PTH in group 1 patients was associated with significant increase in 1,25(OH)(2)D(3) and 1,25(OH)(2)D(3)/PTH ratio. Our data suggest that elevation of serum PTH in eucalcemic patients after parathyroidectomy is a frequently reversible state of resistance of the kidneys to PTH-mediated 1-alpha hydroxylation of 25(OH)D(3) and does not signify subsequent recurrence of hyperparathyroidism.

Progress in the operative management of sporadic primary hyperparathyroidism over 34 years

BACKGROUND

Progress in the diagnosis, localization of abnormal parathyroids, and intraoperative management of primary hyperparathyroidism has been observed over the past 34 years. The goal of this study is to report the outcome of patients undergoing 2 different operative approaches in a single institution, showing the evolution of surgical management of sporadic primary hyperparathyroidism (SPHPT).

METHODS

Parathyroidectomy was performed in 890 (827 initial, 63 reoperative) patients with SPHPT using 2 different approaches: traditional bilateral neck exploration (BNE, n = 396) or limited parathyroidectomy guided by parathormone dynamics (LPX, n = 494). Seven hundred eighteen patients (335 BNE, 383 LPX) followed > or = 6 months or identified as operative failures were studied. Operative failure is defined as hypercalcemia and high intact (1-84) parathyroid hormone molecule (iPTH) within 6 months after operation. Successful parathyroidectomy is normocalcemia for 6 months; hypercalcemia and elevated iPTH after this time is recurrent hyperparathyroidism.

RESULTS

There were 20 (6%) of 335 operative failures in the BNE group and 11 (3%) of 383 failures in the LPX group (P = 0.04). The incidence of multiglandular disease (MGD) determined by gland size (10%) versus hormone hypersecretion (3%) was statistically different (P < 0.001). Since most of the recurrences occurred later than 30 months, the incidence of recurrent hyperparathyroidism in patients followed for longer than 2.5 years was 4% (11/287) in the BNE group (average, 11.5 years) and 3% (5/183) in the LPX group (average, 4.2 years).

CONCLUSION

LPX, with its reported advantages of minimal dissection, shorter operative time, and use in ambulatory settings, compares favorably with the traditional BNE. Parathyroidectomy guided by parathormone dynamics has an improved success rate and should be considered as a standard operative approach in SPHPT.

[Severe primary hyperparathyroidism and vitamin D deficiency]

Primary hyperparathyrodism is a common disease, often asymptomatic. A young post-partum woman was hospitalized for functional impotence of the upper right limb and poor health status. Laboratory tests revealed severe primary hyperparathyroidism (osteitis fibrosa cystica and nephrolithiasis) associated with vitamin D deficiency. Technetium 99m and thallium parathyroid scintigraphy showed increased uptake under the left thyroid lobe. After surgical resection of a parathyroid adenoma, serum calcium fell markedly and parathyroid levels declined but remained above normal. Calcium and 25(OH)-vitamin D supplementation led to normal calcium and vitamin D levels in three Months, with marked improvement in the bone lesions visualized on the six-Month x-rays. Based on this observation, we describe the many radiological aspects of bone involvement in long-standing hyperparathyroidism aggravated by vitamin D deficiency. Early diagnosis of hyperparathyroidism is crucial.

Transient Rise in Intact Parathyroid Hormone Concentration after Surgery for Parathyroid Adenoma

OBJECTIVE: Our goal was to describe the course of parathyroid hormone (PTH) after surgery for primary hyperparathyroidism (PHPT). PTH levels drop to low values after parathyroidectomy for PHPT. However, in some patients, a rebound transient increase in PTH concentrations can occur.

STUDY DESIGN AND SETTING: A prospective study included 72 patients who underwent surgical exploration for PHPT. A single adenoma was found in 57 patients (79.1%), 2 adenomas were found in 2 (2.7%), and parathyroid hyperplasia was found in 13 (18.05%). The postoperative PTH secretion was studied in those patients who had an adenoma excised.

RESULTS: This phenomenon was noted in 18 (31.6%) patients between 4 and 12 weeks, although total calcium concentrations were normal (9.3 ± 0.6 mg/ dL). Before surgery these patients had a more remarkable hyperparathyroidism (clinical and biochemical) than the others, but differences were not significant.

CONCLUSION: Postoperative increases in PTH concentration can occur after successful parathyroidectomy. These increases are transient and do not indicate persistent or recurrent disease.

Elevated serum parathormone level after "concise parathyroidectomy" for primary sporadic hyperparathyroidism

BACKGROUND

Cure after parathyroid exploration is traditionally assessed by serum calcium concentration 6 months postoperatively. Postoperative normocalcemic elevation of serum parathormone (PTH) level has been described but is of unclear significance.

METHODS

In a 6-year prospective study of outcomes in 380 patients undergoing initial parathyroidectomy for primary sporadic hyperparathyroidism, we measured intact serum PTH and calcium levels at more than 5 months. Those with normocalcemic high PTH levels were begun on oral calcium + vitamin supplements and monitored.

RESULTS

At more than 5 months postoperatively, normocalcemic elevation in serum PTH level occurred in 28% of patients, was more common after resection of double adenomas (P =.01), and predated the onset of recurrent hypercalcemia in 3 of 3 patients with unrecognized multiglandular disease. Although delayed treatment with calcium and vitamin supplements produced no clear benefit, patients who took such supplements from the date of surgery were much less likely to have an elevated serum PTH level more than 5 months later (P =.0005).

CONCLUSIONS

After successful parathyroid surgery, compensatory normocalcemic elevation in serum PTH level is frequent and may arise from dietary deficiency. Monitored supplemental intake of calcium and vitamin D appears to prevent or to normalize the condition in most patients. Patients with normocalcemic elevation in serum PTH level should receive evaluation for dietary deficiencies as well as follow-up for possible residual disease.

Normocalcemia with elevated parathyroid hormone levels after surgical treatment of primary hyperparathyroidism

BACKGROUND

Thirty percent of patients who undergo successful parathyroidectomy for primary hyperparathyroidism show unexplained elevated postoperative serum parathyroid hormone (PTH) levels despite normocalcemia.

METHODS

PTH levels were measured monthly in 97 patients for 6 months after parathyroidectomy. Renal function, 25-OH-vitamin D levels, serum alkaline phosphatase levels, osteocalcin, and bone densitometry were evaluated before and 6 months after surgery. PTH reactivity to calcium loading was tested at the sixth month.

RESULTS

Thirty patients had elevated PTH levels despite normocalcemia after parathyroidectomy. Before surgery, these 30 patients had higher PTH and creatinine levels, lower vitamin D levels, and more extensive bone involvement than those with normal postoperative PTH levels. In patients with normal renal function and normal vitamin D levels, postoperative PTH values correlated with preoperative PTH levels but not with bone disease.

CONCLUSION

In most cases, elevated PTH levels after surgery is an adaptive reaction to renal dysfunction or vitamin D deficiency. If no adaptive cause can be found, persistent hyperparathyroidism must be suspected.

Normalization of intraoperative parathyroid hormone does not predict normal postoperative parathyroid hormone levels

BACKGROUND

Intraoperative intact parathyroid hormone (iPTH) is being used to confirm complete excision of hyperfunctioning parathyroid tissue. It is uncertain whether normalization of intraoperative iPTH levels accurately predicts long-term postoperative iPTH values.

METHODS

Fifty-two consecutive patients with primary or secondary hyperparathyroidism underwent parathyroidectomy with measurement of intraoperative iPTH. Ten patients were excluded due to incomplete laboratory follow-up. Follow-up serum calcium and iPTH levels were measured at 1- and 3-month intervals.

RESULTS

Before operation, the mean serum iPTH level was 249 pg/mL (SD=208) and mean serum calcium level was 11.4 +/- 0.9 mg/dL (+/- SD). In all but 4 patients, final intraoperative iPTH levels normalized to less than 67 +/- 41 pg/mL (mean, 35 pg/mL). One week after operation, serum calcium levels had returned to normal (mean, 9.4 +/- 1.1 pg/mL), which directly correlated with the final intraoperative serum iPTH values (Pearson correlation, r = -.434; P <.01). By 1 month, all but 2 patients were normocalcemic (mean, 9.4 +/- 0.9 pg/mL) with a mean iPTH level of 74.8 +/- 82 pg/mL. There was no correlation between final intraoperative and postoperative serum iPTH values (r =.099; P <.533). Both patients with persistent hypercalcemia at 1 month had appropriate intraoperative decreases in iPTH values.

CONCLUSIONS

Intraoperative serum iPTH levels significantly correlate with postoperative serum calcium levels but not with postoperative serum iPTH levels. There was a 4.8% failure rate in the correction of postoperative serum calcium levels and a 29% failure rate in the normalization of postoperative serum iPTH levels.

Late parathyroid function after successful parathyroidectomy guided by intraoperative hormone assay (QPTH) compared with the standard bilateral neck exploration

BACKGROUND

Controversy continues between bilateral neck exploration and limited parathyroidectomy. One approach depends on gland size and histopathologic factors; the other approach limits excision to only hypersecreting glands. Both have excellent early operative success, but late recurrence rates with limited exploration are unknown.

METHODS

Three hundred twenty consecutive patients with primary hyperparathyroidism were followed 6 to 313 months after successful parathyroidectomy. One hundred seventy-six patients had bilateral neck exploration with excision of enlarged glands (group I); 144 patients had glands excised based on hyper-secretion (group II). Calcium and intact parathyroid hormone (iPTH) levels were measured yearly. Parathyroid gland hypersecretion was determined by elevated iPTH levels.

RESULTS

In group I, 1 gland was excised in 160 patients (91%); 19 of 176 patients (11%) had elevated iPTH levels. In group II, 139 patients (97%) had 1 gland excised; 19 of 144 patients (13%) had high iPTH levels. The number of patients with more than 1 gland excised in group I (9%) is 3 times higher than in group II (3%) (P <.05). There was no significant difference in the incidence of recurrent hyperfunctioning glands between the 2 different operative approaches (chi-squared test).

CONCLUSIONS

Late parathyroid gland function was comparable with both approaches. Multiple gland excision based on size alone may lead to excision of normal functioning glands.

Pre- and postoperative bone metabolism of primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is a well-known indicator of severe bone loss. However, the recovery process of bone mineral density after surgery in PHPT patients is not sufficiently clear. We examined postoperative bone metabolism in 24 PHPT patients.

PATIENTS AND METHODS

Subjects were 24 patients with PHPT upon whom we performed parathyroidectomy in the Department of Surgery II, Fukushima Medical University. Mean age was 54.2 years and the male-to-female ratio was 10:14; mean time of follow-up was 27.3 months. Patients were divided histopathologically into 16 adenomas and eight hyperplasias, and classified by heredity into seven familial (six, MEN 1; one, MEN 2) and 17 sporadic types. Bone mineral density was measured by dual energy X-ray absorptometry (DXA) and digital image processing (DIP). Age-matched values of these parameters were obtained. Serum bone metabolic parameters; ionized calcium (CaF), phosphorus, intact PTH (iPTH), c-PTH, ALP, osteocalcin (OC) and PTHrP were measured.

RESULTS

PHPT patient preoperative bone mineral densities were significantly lower than those of healthy controls. Those by DIP method were lower than those by DXA. High CaF, iPTH, OC and ALP levels were indicated before surgery, but all parameters immediately became normal. Longitudinal bone mineral density changes of asymptomatic cases increased more than those of patients with renal stone and/or ostitis fibrosa. In adenoma cases, tumor weights were significantly inversely, which correlated with preoperative DIP bone density measurements.

CONCLUSION

Preoperative PHPT patients showed decreased bone density; bone loss in symptomatic cases was especially prominent compared to asymptomatic cases. Most PHPT patients had not completed the BMD recovery after surgery, so even asymptomatic and mild PHPT patients should undergo parathyroidectomy to minimize irreversible bone loss.

Secondary hyperparathyroidism is an expected consequence of parathyroidectomy for primary hyperparathyroidism: a prospective study

BACKGROUND

Parathyroidectomy for primary hyperparathyroidism (PHPT) can cause secondary hyperparathyroidism, with increased serum parathyroid hormone (PTH) and normal or low serum calcium concentrations.

METHODS

A prospective study investigated 78 consecutive patients who underwent exploration for PHPT. Serum intact PTH and total calcium concentrations were measured the evening after operation and ionized Ca++ the following morning. These levels were reassayed 1 week later.

RESULTS

Before operation, the mean PTH level was 138 +/- 15 pg/mL, total calcium concentration was 11.6 +/- 0.1 mg/dL, and ionized Ca++ concentration was 1.44 +/- 0.02 mmol/L. On the night of the operation, the PTH level was 11 +/- 2 pg/mL, and the total calcium concentration was 8.9 +/- 0.1 mg/dL. Fifty-five patients had hypoparathyroidism, with a PTH level less than 10 pg/mL. The day after the operation, the ionized Ca++ level was 1.14 +/- 0.01 mmol/L. One week later, PTH, ionized Ca++, and total serum calcium concentrations returned to normal levels. In 9 patients (12%), PTH levels were increased (98 +/- 16 pg/mL), although ionized Ca++ concentrations were normal (1.18 +/- 0.02 mmol/L), demonstrating secondary hyperparathyroidism. Risk factors for postoperative secondary hyperparathyroidism included older age, symptomatic hyperparathyroidism, higher preoperative PTH and alakaline phosphatase levels, and lower serum phosphorous levels. In 70% of these patients, PTH levels returned to normal in 3 to 12 months.

CONCLUSIONS

Secondary hyperparathyroidism occurs in 12% of patients after surgical treatment of PHPT. It is transient, possibly compensating for relative hypocalcemia.