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.     

Risk factors for severe postoperative hypocalcaemia after operations for primary hyperparathyroidism.

OBJECTIVE: To identify risk factors for severe hypocalcaemia after surgery for primary hyperparathyroidism. DESIGN: Retrospective study followed by a prospective study. SETTING: University hospital, Denmark. PATIENTS: 340 consecutive patients, operated on from 1991 to 1999, and 85 consecutive patients operated on in 2000. MAIN OUTCOME MEASURES: Predictive value of identified risk factors. RESULTS: Incisional biopsy or excision of more than 2 parathyroid glands, thyroid operation together with parathyroidectomy, preoperative serum concentration of parathyroid hormone of more than 25 pmol/L, or a history of previous operations on the neck, were identified retrospectively as risk factors for severe postoperative hypocalcaemia. In the prospective study these factors showed a sensitivity of 100% (9/9), and a specificity of 25% (9/36). We found no risk of severe hypocalcaemia after parathyroidectomy in patients without these risk factors. The risk increased to 37% (7/19) if serum concentration of parathyroid hormone was more than 25 pmol/L, or if thyroidectomy was done together with parathyroidectomy. CONCLUSIONS: Patients with no risk factors for severe hypocalcaemia can be discharged early from hospital. Special attention should be given to patients with one or more risk factors for severe hypocalcaemia.     

Risk assessment for severe postoperative hypocalcaemia after neck exploration for primary hyperparathyroidism.

BACKGROUND AND AIMS: A further development of the risk profile for severe postoperative hypocalcaemia after surgery for primary hyperparathyroidism (pHPT) was made with the aim of expanding the group of patients who can be discharged safely after 23 hours. METHODS: Prospective study with 156 consecutive pHPT patients (158 operations) during 2001 and 2002. Risk factors for postoperative severe hypocalcaemia (ionised calcium < 1 mmol/L), were (1) preoperative concentration of parathyroid hormone (PTH) > 35 pmol/L (five times the upper reference value, reference range 1.1 to 6.9), (2) history of previous neck surgery, (3) biopsy/excision of > 2 parathyroid glands or (4) concomitant thyroid surgery. RESULTS: The risk factors showed a sensitivity of 100 % (9/9). In 110 of the operations (70%) no risk factors were identified. Postoperative calcium levels were significantly lower after 48 operations with risk factor(s) identified, as compared to the group without risk factors (p < 0.01). Seven of 17 patients (41%) with PTH > 35 pmol/L developed severe postoperative hypocalcaemia. Two of 31 patients (6%) with PTH < 35 pmol/L in the presence of other risk factor(s) developed severe postoperative hypocalcaemia. CONCLUSION: Patients with no risk factor can safely been discharged from hospital on the first postoperative day. Patients with preoperative concentration of PTH > 35 pmol/ L (five times the upper reference value) should stay in hospital until nadir level of calcium is reached. Patients with concentration of parathyroid hormone less than 35 pmol/ L in the presence of other risk factor(s) may have an early discharge from hospital (second postoperative day) combined with outpatient measurements of calcium levels.     

Experienced radio-guided surgery teams can successfully perform minimally invasive radio-guided parathyroidectomy without intraoperative parathyroid hormone assays

Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperparathyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-guided parathyroidectomy (MIRP) performed using preoperative sestamibi localization studies, intraoperative gamma detection probe, and the selective use of frozen section pathology without the use of iPTH. This is a single institution review of patients with primary hyperparathyroidism treated with MIRP by surgeons experienced in radio-guided surgery between October 1, 1998 and July 15, 2005. Information was obtained by reviewing computer medical records as well as contacting primary care physicians. Factors evaluated included laboratory values, pathology results, and evidence of recurrence. One hundred forty patients were included with a median preoperative calcium level of 11.3 mg/dL (range, 9.6-17) and a PTH level of 147 pg/mL (range, 19-5042). The median postoperative calcium level was 9.3 mg/dL. All patients were initially eucalcemic postoperatively except for one who had normal parathyroid levels. However, five (4%) patients required re-exploration for various reasons. Of the failures, one was secondary to the development of secondary hyperparathyroidism, and therefore would not have benefited from iPTH, one had thyroid tissue removed at the first operation, and three developed evidence of a second adenoma. One of these three patients had a drop in PTH level from 1558 pg/mL preoperatively to 64 pg/mL on postoperative Day 1, indicating that iPTH would not have prevented this failure. Thus, only three (2.1%) patients could have potentially benefited from the use of iPTH. MIRP was successful in 96 per cent of patients using a combination of preoperative sestamibi scans, intraoperative localization with a gamma probe, and the selective use of frozen pathology. This correlates with reported success rates of 95 per cent to 100 per cent using iPTH. We conclude that minimally invasive parathyroidectomy can be successfully performed without using iPTH assays.     

Unilateral versus bilateral neck exploration for primary hyperparathyroidism: five-year follow-up of a randomized controlled trial

OBJECTIVE: To compare long-term patient outcome in a prospective randomized controlled trial between unilateral and bilateral neck exploration for primary hyperparathyroidism (pHPT). SUMMARY BACKGROUND DATA: Minimal invasive and/or focused parathyroidectomy has challenged the traditional bilateral neck exploration for pHPT. Between 1997 and 2001, we conducted the first unselected randomized controlled trial of unilateral versus bilateral neck exploration for pHPT. The results showed that unilateral exploration is a surgical strategy with distinct advantages in the early postoperative period. However, concerns have been raised that limited parathyroid exploration could increase the risk for recurrent pHPT during long-term follow-up. METHODS: Ninety-one patients with the diagnosis of pHPT were randomized to unilateral or bilateral neck exploration. Preoperative scintigraphy and intraoperative parathyroid hormone measurement guided the unilateral exploration. Gross morphology and frozen section determined the extent of parathyroid tissue resection in the bilateral group. Follow-up was performed after 6 weeks, 1 year, and 5 years postoperatively. RESULTS: Seventy-one patients were available for 5-year follow-up. There were no differences in serum ionized calcium and parathyroid hormone, respectively, between patients in the unilateral and bilateral group. Overall 6 patients have been found to have persistent (n = 3) or recurrent (n = 3) pHPT; 4 patients in the unilateral group (3 of these 4 patients were bilaterally explored) and 2 patients in the bilateral group. Three of 6 failures were unexpectedly found to have multiple endocrine neoplasia mutations. One patient with solitary adenoma in the bilateral group still required vitamin D substitution 5 years after surgery. CONCLUSION: Unilateral neck exploration with intraoperative parathyroid hormone assessment provides the same long-term results as bilateral neck exploration, and is thus a valid strategy for the surgical treatment of pHPT.     

Primärer Hyperparathyreoidismus

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 287pg/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.     

How low is too low? Intraoperative parathyroid hormone decline in normohormonal primary hyperparathyroidism

BackgroundIn normohormonal primary hyperparathyroidism, parathyroid hormone levels are normal but inappropriately elevated for the degree of hypercalcemia. The study goals were to determine intraoperative parathyroid hormone parameters predictive of (1) cure and (2) hypocalcemia in this subgroup.MethodsWe performed a retrospective cohort study comparing patients who underwent parathyroidectomy (2002–2019) for normohormonal and classic primary hyperparathyroidism. The primary outcomes were cure (calcium <10.3 mg/dL) and hypocalcemia (≤8.4 mg/dL) ≥6 months postoperatively.ResultsIn the study, 127 of 1,087 patients (11.7%) had normohormonal primary hyperparathyroidism. The groups experienced similar rates of cure (91.3% vs 94.1%, P = .23) and hypocalcemia (3.9% vs 2.9%, P = .53). However, intraoperative parathyroid hormone decline in cured patients was lower in those with normohormonal primary hyperparathyroidism (66.4% vs 84.5%, P < .0001). Receiver operating characteristic curves provided Youden’s indices of 52% and 75% (cure) and 75% and 88% (hypocalcemia) for patients with normohormonal and classic primary hyperparathyroidism, respectively. Cure rates with ≥50% intraoperative parathyroid hormone decline were similar (94.1% vs 95.0%, P = .72), but hypocalcemia was more prevalent in patients with normohormonal primary hyperparathyroidism and ≥70% intraoperative parathyroid hormone decline (10.4% vs 3.3%, P = .01).ConclusionIn patients with normohormonal primary hyperparathyroidism, intraoperative parathyroid hormone declines of ≥50% and ≥70% were predictive of postoperative cure and hypocalcemia, respectively. These parameters may inform intraoperative decision making and postoperative management.     

Use of monitoring intraoperative parathyroid hormone during parathyroidectomy in patients on waiting list for renal transplantation

This report describes the use of intraoperative parathyroid hormone (ioPTH) assay during parathyroidectomy for patients with secondary hyperparathyroidism on the waiting list for renal transplantation. The levels of ioPTH were determined among waiting list patients undergoing subtotal parathyroidectomy and tertiary hyperparathyroidism patients undergoing procedures. The levels of ioPTH were significantly reduced at 10 minutes by 59.7,3% among with secondary hyperparathyroidism and 68.9% among tertiary hyperparathyroidism. A 15 minutes it was 85% in secondary hyperparathyroidism and 89.7% in tertiary hyperparathyroidism. A decrement of 50% in basal values at 10 minutes and 85% decrement or more at 15 minutes was predictive for the success of abnormal parathyroid gland removal. The application of this technique during subtotal parathyroidectomy results was useful to predict a correct excision of abnormal parathyroid glands among patients with secondary hyperparathyroidism on the waiting list and for tertiary hyperparathyroidism patients.     

Diminished dose minimally invasive radioguided parathyroidectomy: a case for radioguidance

Minimally invasive radioguided parathyroidectomy (MIRP) has been established as an alternative to bilateral neck exploration (BNE) for primary hyperparathyroidism. We investigate whether a diminished dose of technetium-99m sestamibi gives similar results to the standard dose. One hundred one patients were offered MIRP or diminished-dose MIRP (ddMIRP). Patients received intravenous Tc-99m sestamibi at a dose of either 25 mCi 1.5 hours or 5 mCi 1 hour preoperatively. The procedure was terminated when the 20 per cent rule was satisfied. All tissue was confirmed to be parathyroid tissue by frozen section analysis. In addition, intraoperative parathyroid hormone levels were measured in a majority of patients. Patients who failed IOM underwent BNE. Frozen section analysis and intraoperative parathyroid hormone monitoring were also performed in the BNEs. Postoperatively, serum calcium levels were measured at 1 week and 6 months. Fifteen per cent of patients were male and 85 per cent were female. The median age was 63 years (range, 25-89 years). The first 58 patients had the standard dose of 25 mCi, whereas 43 patients had ddMIRP. Six patients (10%) failed intraoperative mapping in the MIRP group and were found to have single-gland disease. Five patients (12%) failed intraoperative mapping in the ddMIRP group. However, two patients were identified to have multigland disease making the true failure rate of intraoperative mapping 7 per cent (three patients). Median operative times for MIRP, ddMIRP, and BNE were 40 minutes, 46 minutes, and 105 minutes, respectively. The 20 per cent rule was satisfied in 96 per cent of patients undergoing MIRP and 98 per cent of patients undergoing ddMIRP. Frozen section analysis and intraoperative parathyroid hormone monitoring did not result in a change in management. Median follow up was 193 days and serum calcium levels at 6 months were normal. Diminished-dose MIRP is a feasible alternative to standard-dose MIRP without compromising surgical outcomes.     

Minimally invasive parathyroid surgery, the Norman 20% rule: is it valid?

The 20 per cent rule proposed by Norman established a guideline using radioactivity in the minimally invasive radioguided parathyroidectomy (MIRP) technique to localize and confirm removal of an abnormal parathyroid gland in patients with primary hyperparathyroidism. If radioactivity in the resected gland was at least 20 per cent of excision site/background radioactivity, the 20 per cent rule was satisfied. Patients meeting these criteria underwent unilateral MIRP without intraoperative parathyroid hormone assay or intraoperative frozen section. The study aim was to independently evaluate the 20 per cent rule in MIRP patients with primary hyperparathyroidism. Using the University of Louisville Parathyroid Database from January 1, 1999 to December 31, 2007, 216 MIRP patients with complete radioguided and postoperative management data were identified. The average percentage of ex vivo parathyroid gland radioactivity compared with excision site/background radioactivity was 107 per cent with a range from 14 to 388 per cent. For 99 per cent (196/198) radioactivity recorded from the excised gland was at least 20 per cent of radioactivity recorded from the excision site. Normocalcemia was documented in 98.5 per cent (195/198) at 12 month follow-up. Our data supports the 20 per cent rule in that in 99 per cent of MIRP patients the resected gland radioactivity was at least 20 per cent of excision site radioactivity allowing localization and confirmation of an overactive gland without intraoperative parathyroid hormone monitoring or tissue analysis.     

Surgeon-performed ultrasound improves localization of abnormal parathyroid glands

With a secure diagnosis of hyperparathyroidism, preoperative localization of abnormal glands is the initial step toward limited parathyroidectomy (LPX). We investigated whether ultrasonography in the hands of the surgeon (SUS) could improve the localization of abnormal parathyroids when sestamibi scans (MIBI) were negative or equivocal. One hundred eighty patients with sporadic primary hyperparathyroidism (SPHPT) underwent preoperative SUS and MIBI scans before LPX guided by intraoperative parathormone assay. When the sestamibi scans were negative, SUS was used to localize the parathyroid, distinguish parathyroid from thyroid tissue, and to guide the intraoperative jugular venous sampling for differential elevation of parathyroid hormone (PTH). Operative findings, intraoperative hormone dynamics, and postoperative calcium levels determined successful localization. MIBI was negative or equivocal in 36/180 (20%) patients: (1) showed no parathyroid gland in 22 patients, (2) suggested an incorrect location for the abnormal gland in 9, and (3) was insufficient in recognizing multiglandular disease in 5. In these 36 patients, the addition of SUS led to the successful identification of the abnormal tissue in 19/36 (53%). In the remaining 17 patients with negative/equivocal scans, the parathyroid could not be clearly visualized by SUS. In these patients, SUS facilitated LPX by aiding preoperative transcutaneous jugular venous sampling for differentially elevated PTH (n=3) and identifying questionable thyroid nodule versus parathyroid tissue (n=1). Overall, SUS was useful in 23/36 (67%) patients with nonlocalizing MIBI scans, thus improving the rate of localization from 80 per cent to 93 per cent (P < 0.01). Surgeon-performed cervical ultrasonography improved the localization of abnormal parathyroids by MIBI scan, adding to the success of limited parathyroidectomy.     

Persistent Hypocalcemia with Elevated Parathyroid Hormone Levels After Long-Term Primary Hyperparathyroidism: Report of a Case

We report herein the case of a 48-year-old man with long-term persistent primary hyperparathyroidism (pHPT) despite undergoing a parathyroidectomy in 1976, followed by a reoperation in 1978, for whom resection of a parathyroid adenoma in the upper mediastinum was eventually performed. His postoperative course was complicated by recurrent hypocalcemia refractory to oral calcium substitution and significantly elevated levels of parathyroid hormone (PTH). The radiological findings are presented, and we discuss the possible reasons for the coincidence of severe hypocalcemia with increased PTH levels in association with pHPT. Received: October 18, 1999 / Accepted: May 30, 2000     

Hypocalcemia after neck exploration for untreated primary hyperparathyroidism

Hypocalcemia after neck exploration for hyperparathyroidism is an important postoperative management issue. With increasing acceptance of less invasive surgical approaches, hypocalcemia is less frequent. This study was conducted to evaluate postoperative hypocalcemia after current surgical exploration techniques in patients with untreated primary hyperparathyroidism. From the University of Louisville parathyroid database, charts of patients undergoing surgery for untreated primary hyperparathyroidism from May 1, 1998 to May 30, 2004 were reviewed. Data was analyzed based on age, sex, preoperative calcium and parathyroid hormone levels, preexisting diseases, and extent of neck exploration. One hundred sixty-nine patients were identified with adequate data for analysis. Transient postoperative hypocalcemia occurred in 21 per cent (36/169) for the total group, in 18 per cent (22/125) after minimally invasive radio-guided parathyroidectomy, and in 32 per cent (14/44) after bilateral neck exploration. Patients with postoperative hypocalcemia had a statistically significant association with older age and pre-existing hypertension. Patients with postoperative hypocalcemia were more likely to have undergone longer surgical procedures and were more likely to have had pre-existing diabetes and mental disorders. These findings were not statistically significant and were considered trends. The frequency of osteoporosis in the hypocalcemia group was increased but was not significant. Transient hypocalcemia occurred in 21 per cent of patients after parathyroid surgery. It was more likely after bilateral neck exploration, a longer duration of surgery, and with hypertension, diabetes, and mental disorders.     

Minimally invasive video-assisted parathyroidectomy and intraoperative parathyroid hormone monitoring. The first 36 cases and some pitfalls

Background: The success of parathyroid surgery depends on the identification and removal of all hyperactive parathyroid tissue. At this writing, bilateral cervical exploration and identification of all parathyroid glands represent the operative standard for primary hyperparathyroidism (pHPT). However, improved preoperative localization techniques and the availability of intraoperative parathyroid hormone monitoring prepare the way for minimally invasive procedures. Methods: Patients with pHPT and one unequivocally enlarged parathyroid gland on preoperative ultrasound and 99mTc-SestaMIBI scintigraphy underwent minimally invasive video-assisted parathyroidectomy by an anterior approach. Intraoperatively, a rapid chemiluminescense immunoassay was used to measure intact parathyroid hormone (iPTH) levels shortly before and then 5, 10, and 15 min after excision of the adenoma. The operation was considered successful when more than a 50% decrease in preexcision iPTH levels was observed after 5 min. Results: Between October 1999 and November 2001, 36 of 82 patients with pHPT were eligible for a minimally invasive approach. A conversion to open surgery became necessary in five patients because of technical problems. In three cases, intraoperative iPTH monitoring showed no sufficient decrease in iPTH values. In these cases, subsequent cervical exploration showed one double adenoma and two hyperplasias, respectively. In two patients we had difficulty interpreting intraoperative iPTH values, resulting in persistent pHPT. Conclusions: Despite the use of high-resolution ultrasound and 99mTc-SestaMIBI scintigraphy, the presence of multiple glandular disease cannot be ruled out completely. Intraoperative iPTH monitoring to ensure operative success is indispensible for a minimally invasive approach. Despite our problems with iPTH monitoring in two patients, we believe that in selected cases, minimally invasive parathyroidectomy represents an attractive alternative to conventional surgery.     

Intraoperatives Parathormonmonitoring bei der Halsexploration wegen renalem Hyperparathyreoidismus?

Introduction. In operations for renal hyperparathyroidism the value of intraoperative parathormone monitoring was investigated. Patients and methods. Intraoperative intact parathyroid hormone levels were determined (PTH Quick assay) in 40 patients undergoing first cervical exploration and in two patients with graft-dependent recurrence of renal hyperparathyroidism. Results. In 33 patients, total parathyroidectomy with autotransplantation was carried out. The median parathormone levels decreased from 652 pg/ml to 120 pg/ml (19% of initial level) 5 min after total parathyroidectomy. In seven patients, fewer than 4 parathyroid glands each were identified during cervical exploration and “total parathyroidectomy (?)” without autotransplantation was performed. Intraoperatively median parathormone level decreased from 1193 pg/ml to 116 pg/ml (10% of initial level). In one of these seven patients, hyperparathyroidism persisted due to an ectopic fourth gland within the carotid sheath. In two of these patients, hypoparathyroidism occurred and a delayed autotransplantation of cryopreserved parathyroid tissue was carried out. On the first day after total parathyroidectomy with autotransplantation and “total parathyroidectomy (?)”, median levels of intact parathyroid hormone were 1.9 pg/ml and 82.5 pg/ml, respectively. Conclusion. Intraoperative monitoring is not useful in first cervical exploration for renal hyperparathyroidism because it cannot predict complete resection of parathyroid tissue. The parathormone level on the first postoperative day allows precise evaluation of the efficacy of the surgical procedure.     

Prediction of bone mass gain by bone turnover parameters after parathyroidectomy for primary hyperparathyroidism: neural network software statistical analysis

BACKGROUND: Primary hyperparathyroidism (pHPT) is the most frequent endocrine hypersecretion disease, and parathyroidectomy is the only curative option, since pharmacologic therapy reduces hypercalcemia but does not impede parathyroid hormone hypersecretion. According to guidelines from the National Institutes of Health, parathyroidectomy is associated with bone mass increase in some asymptomatic patients, while in others bone mass is not changed after surgery. Therefore, we performed the present study in an attempt to elucidate whether a preoperative biochemical bone parameter can be predictive of a significant vertebral bone mass increase in patients with pHPT. METHODS: For each patient we analyzed the following preoperative parameters: parathyroid hormone, urinary calcium excretion, urinary type I collagen cross-linked N-telopeptide (NTX), osteocalcin, and vertebral computerized bone mineralography. All patients underwent vertebral computerized bone mineralography 12 months after the operation. Statistical analysis was carried out by a neural network program, an event-predicting software modeled on human brain neuronal connections, which is able to examine independent statistical parameters. RESULTS: The patients presenting with high preoperative bone turnover (especially high NTX levels) will have a 5% vertebral bone mass gain in 83.33% of cases after surgery, independently of the National Institutes of Health guidelines. CONCLUSIONS: A high preoperative NTX level seems to be the best predictor parameter for postoperative vertebral bone mass gain in patients with pHPT. Our study also illustrates that neural network software may be a valuable method to help elucidate which pHPT patients should undergo surgical treatment.     

Intraoperative calcium monitoring is insufficient to predict the surgical success of parathyroidectomy for primary hyperparathyroidism

Purpose  

Serum calcium has been suggested to be a surrogate marker for intraoperative monitoring during a parathyroidectomy (PTX) for primary hyperparathyroidism (pHPT). The objective of the present prospective study was to investigate whether serum calcium can be used as an alternative for parathyroid hormone intraoperative monitoring.     

Parathyroidectomy: new criteria for evaluating outcome

Following successful parathyroidectomy, subjective improvement in recognized symptoms and in the overall "well being" of asymptomatic primary hyperparathyroid patients has been well documented. Because quantitative methods for measuring parathyroid hormone (PTH) and normal reference ranges of serum calcium have changed in recent years, a revised biochemical criteria for evaluating postoperative outcome has become necessary. Two hundred seventy-one selected patients were followed for an average of 6.3 years after parathyroidectomy. Although 257 patients had serum calcium levels <10.6 mg/dL during the entire follow-up period, 15 per cent of them had elevated intact PTH (iPTH) levels. Fourteen patients had calcium levels > or =10.6 mg/dL at some point during follow-up, with nine patients (64%) showing high iPTH levels and eight (57%) of them developing recurrent hyperparathyroidism (calcium > or =11 mg/dL and iPTH > or =68 pg/mL). Of the 14 remaining patients, 5 had hypercalcemia with normal iPTH levels. In patients with successfully treated primary hyperparathyroidism, the recommended annual follow-up is: 1) monitor total serum calcium only if serum calcium level is <10.6 mg/dL, or if serum calcium level is > or =10.6 mg/dL; and 2) monitor serum calcium and PTH levels, because these patients have an increased incidence of hyperfunctioning parathyroid glands, which may point to late recurrence.     

Results and complications of parathyroidectomy in secondary hyperparathyroidism

Retrospective study was performed to measure the results of parathyroidectomy in patients with secondary hyperparathyroidism. From 1987 to 2000, 48 patients underwent surgery for secondary hyperparathyroidism. There were 30 of 48 patients on haemodialysis treatment, and 11 patients were in pre-dialysis stage. Parathyroidectomy was performed after successful kidney transplantation in 4 cases. Indication of the surgery was extremely elevated serum level of parathyroid hormone (at least 10 fold elevation), which was resistant for the conservative medical therapy. Subtotal parathyroidectomy (3 1/2) was performed in 30 patients. Five patients underwent total parathyroidectomy and autotransplantation. Only 2 or 3 parathyroid glands have been removed in 13 patients. Haematoma occurred in 3 cases after parathyroidectomy. Recurrent nerve injury or septic complication did not occur. Two patients died in the early postoperative period due to cardiac failure. Tetania was noted in 2 patients after surgery. Permanent postoperative hypocalcaemia (over 6 months) occurred in 3 cases. Persistent hyperparathyroidism was diagnosed in 5 patients. In these patients 2 parathyroid glands were removed during the primary operation. Recurrent hyperparathyroidism was detected in 2 patients. Subtotal parathyroidectomy was carried out in these cases previously. At the reoperation for persistent and recurrent hyperparathyroidism, total parathyroidectomy and autotransplantation was performed. Serum alkaline phosphatase level and serum parathyroid hormone value decreased after surgery, except those patients with persistent hyperparathyroidism. Bone pain decreased in 96% of the cases and pruritus decreased in 92% of the patients after parathyroidectomy. Soft tissue calcification showed improvement in 45% of cases. In conclusion, the subtotal parathyroidectomy or total parathyroidectomy with autotransplantation cause a rapid decrease of PTH level and the improvement of the clinical symptoms in patients with medical treatment resistant secondary hyperparathyroidism. Persistent hyperparathyroidism occurs in those cases when inadequate parathyroidectomy was performed.     

The effect of parathyroidectomy on the recurrence of nephrolithiasis

Little information is available on the long-term influence of parathyroidectomy on the rate of renal stone formation in patients with primary hyperparathyroidism (pHPT) and nephrolithiasis. The reported occurrence of renal stone disease in untreated patients with pHPT is 15% to 30%. A registry of 258 pHPT patients who underwent parathyroidectomies at the Milwaukee Regional Medical Center has allowed continued follow-up of the 71 (28%) pHPT patients with associated renal stone disease. Patients have been followed up for an average of 5 years (range, 1 to 15 years) since surgery. The rate of renal stone formation before and after parathyroidectomy was compared. Identification of a "new" renal stone was defined as passage and collection, extraction, or radiographic visualization of stones. All 71 pHPT patients with stone disease had hypercalcemia and inappropriately elevated parathyroid hormone concentrations, and after parathyroidectomy these values returned to normal in 69 of 71 patients. Since undergoing parathyroidectomy, only 4 patients have passed renal stones. The rate of stone formation per patient per year was 0.36 before and 0.02 after surgery (p less than 0.001). Surgical correction of pHPT significantly reduced the rate of stone formation.